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1.
Phys Chem Chem Phys ; 24(48): 29328-29332, 2022 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-36399150

RESUMO

Oxide layers on conductive TiN have recently been investigated to catalyse the oxygen reduction reaction (ORR) in acidic media. The ORR reactivity, i.e., activity and selectivity, has been correlated with the surface nitrogen atoms. A new strategy, optimising the work function via the doping of foreign metals, is revealed herein to enhance the reactivity.

2.
RSC Adv ; 12(3): 1850-1854, 2022 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-35425165

RESUMO

Dual-functional catalysis indicates that an organic p-n bilayer induces the catalytic oxidation involved in downhill reactions, not only under illumination but also in the dark. When the organo-bilayer is composed of a perylene derivative (3,4,9,10-perylenetetracarboxylic-bis-benzimidazole (PTCBI), n-type) and cobalt phthalocyanine (CoPc, p-type), only the photocatalytic oxidation of hydrazine (N2H4) occurs. However, the loading of Ag co-catalyst onto the CoPc surface in the PTCBI/CoPc bilayer successfully led to dual catalysis in terms of the oxidation of N2H4 to N2. To develop the present dual catalysis Ag loading was essential to achieve the catalysis performance particularly without irradiation.

3.
J Gen Fam Med ; 21(6): 282-287, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33304730

RESUMO

BACKGROUND: In Japan, even if physicians have not experienced surgical training, they face many instances in which they must provide initial surgical treatment, especially during off-hours. This study aimed to identify the frequency and fields of commonly encountered problems in a Japanese emergency department. METHODS: A retrospective review was performed to identify walk-in outpatients with exogenous problems visiting during off-hours in the Japanese educational hospital providing primary to tertiary emergency care between January 1 and December 31, 2014. Diseases were aggregated according to International Classification of Primary Care (Second Edition; ICPC-2). RESULTS: During the study period, 33 424 patients visited and 7476 were classified into the "exogenous" group. We analyzed the data of 7421 patients after excluding 55 who were deemed undiagnosable based on reviews of the charts. The median age of patients who visited the ED during off-hours was 29 years (range: 0-101 years, IQR: 8-60 years). Altogether, 226 types of problems included in ICPC-2 were identified during the study period. The majority fields of exogenous problems were 'skin,' 'Musculoskeletal,' and 'eye.' The 15 problems with the highest frequencies accounted for 50.2% of the total problems. CONCLUSIONS: We identified surgical problems with high treatment frequencies among patients visiting the ED during off-hours. Providing education focusing on these frequent surgical problems can help to improve the initial treatment quality and reduce the anxiety for those doctors who provide initial surgical treatment.

6.
Intern Med ; 58(2): 271-276, 2019 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-30146564

RESUMO

Diffuse idiopathic skeletal hyperostosis (DISH) is a relatively common progressive noninflammatory entheses disease. Patients are often asymptomatic or are undiagnosed due to minor chronic symptoms. We herein report a rare case in which the primary symptom was sudden-onset upper airway obstruction due to exuberant osteophytosis in the cervical spine. Treatment was successful with careful airway management and surgical osteophyectomy. Most DISH cases in the literature with airway obstruction have been managed with tracheotomy. However, the safety and necessity of this approach remain questionable. We herein discuss the possibility of conservative management as a choice of airway control. Airway obstruction due to DISH may be underrecognized. This highlights the importance of including DISH in the differential diagnosis of airway obstruction. In addition, a detailed evaluation and personalized care for each individual case is essential.


Assuntos
Obstrução das Vias Respiratórias/etiologia , Obstrução das Vias Respiratórias/terapia , Hiperostose Esquelética Difusa Idiopática/complicações , Hiperostose Esquelética Difusa Idiopática/cirurgia , Idoso de 80 Anos ou mais , Vértebras Cervicais/cirurgia , Descompressão Cirúrgica , Transtornos de Deglutição/etiologia , Transtornos de Deglutição/terapia , Diagnóstico Diferencial , Humanos , Hiperostose Esquelética Difusa Idiopática/diagnóstico , Masculino , Sucção
7.
Intern Med ; 58(8): 1097-1101, 2019 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-30568111

RESUMO

Pancreatic cysts include a variety of benign, premalignant, and malignant lesions. Endometrial cysts in the pancreas are extremely rare lesions that are difficult to diagnose before surgery. We report the case of a 26-year-old patient with a recent episode of left abdominal pain who presented with a large cyst in the pancreatic body. Laboratory results showed white blood cell and C-reactive protein elevation, whereas the patient's tumor marker levels were within the normal range. Distal pancreatectomy with splenectomy was performed. The final histopathological examination confirmed the presence of endometriotic cysts within the pancreas. Only 13 cases of endometriotic cysts of the pancreas have been previously reported. The preoperative diagnosis is challenging, and most patients undergo pancreatic resection because of suspected neoplasms. This case report reviews previous studies and discusses the clinicopathological features, pathogenesis, and appropriate treatment for pancreatic endometrial cysts.


Assuntos
Dor Abdominal/etiologia , Endometriose/complicações , Pancreatectomia/métodos , Cisto Pancreático/etiologia , Cisto Pancreático/cirurgia , Neoplasias Pancreáticas/cirurgia , Doenças Raras/cirurgia , Adulto , Idoso , Feminino , Humanos , Pessoa de Meia-Idade , Cisto Pancreático/diagnóstico , Cisto Pancreático/patologia , Neoplasias Pancreáticas/diagnóstico , Doenças Raras/diagnóstico , Resultado do Tratamento , Adulto Jovem
8.
Chem Commun (Camb) ; 52(49): 7735-7, 2016 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-27242136

RESUMO

This study examined a water-splitting system comprising a TiO2 photoanode and an organo-photocathode consisting of a p-n bilayer. Stoichiometric decomposition of water into H2 and O2 successfully occurred at bias voltages lower than the theoretical value (i.e. 1.23 V). Compared to the conventional TiO2 and Pt systems, the proposed water-splitting system demonstrated water splitting without any externally applied bias.

9.
Chem Commun (Camb) ; 50(16): 1950-2, 2014 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-24409454

RESUMO

An organic p-n bilayer photocatalysis system successfully induced the oxidative decomposition of hydrazine (N2H4) into N2 and simultaneously yielded H2 from H(+). This demonstrates the first instance of the stoichiometric decomposition of N2H4 under visible-light irradiation.

10.
ACS Appl Mater Interfaces ; 5(4): 1248-53, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23363482

RESUMO

The photoelectrode characteristics of an organic p/n bilayer in the water phase were studied with respect to film; 3,4,9,10-perylenetetracarboxylic-bisbenzimidazole (PTCBI, an n-type semiconductor) was used in combination with 29H,31H-phthalocyanine (H2Pc, a p-type semiconductor). When H2Pc was vapor-deposited on top of the PTCBI layer on a heated substrate (cf. degree of pressure, ca. 5.0 × 10⁻4 Pa; temperature at the substrate, 120°C), a transmission electron microscopic image showed an enhanced contact area of the p/n interface in comparison with that prepared at r.t., due to the formation of a whisker H2Pc. The PTCBI/H2Pc bilayer can work as a photoanode along with photophysical events in its interior. The rate-limiting charge transfer at the H2Pc/water interface was kinetically analyzed assuming the Langmuir adsorption equilibrium at that interface. Kinetic analysis demonstrated that the increased contact area can successfully lead to efficient photoinduced carrier generation; particularly, when a thick whisker of H2Pc was formed, the magnitude of the oxidation kinetics at the H2Pc/water interface was approximately 2.5 times higher than that without thermal treatment.

11.
Molecules ; 17(9): 10801-15, 2012 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-22964498

RESUMO

Photoelectrochemical measurements were used to study the photoelectrode characteristics of composite nanoparticles composed of fullerene C60 and partially hydrolyzed aluminum phthalocyanine chloride (AlPc). In cyclic voltammetry measurements, the electrodes coated with the composite nanoparticles were found to have photoanodic [electron donor: 2-mercaptoethanol (ME)] and photocathodic (electron acceptor: O2) characteristics similar to those of the vapor-deposited p/n junction electrode. Their photoanodic features were further investigated with respect to the transient photocurrent response to light irradiation and the dependence on ME concentration (under potentiostatic conditions), from which it was noted that there was a decrease in the initial spiky photocathodic current and saturation of the steady-state photoanodic current at a higher ME concentration. Thus, the reaction kinetics was probably dominated by charge transport process. Moreover, external and internal quantum efficiency spectrum measurements indicated that the composite nanoparticles responded to the full spectrum of visible light ( < 880 nm) for both the photoanodic and photocathodic current. The present research will assist comprehension of photocatalytic behavior of the composite nanoparticles.


Assuntos
Fulerenos/química , Indóis/química , Nanopartículas/química , Compostos Organometálicos/química , Catálise , Eletricidade , Eletroquímica , Eletrodos , Luz , Oxirredução , Processos Fotoquímicos , Espectroscopia Fotoeletrônica , Semicondutores
13.
ACS Appl Mater Interfaces ; 3(6): 1902-9, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21604785

RESUMO

The visible-light-responsive photoelectrochemical and photocatalytic properties of nanoparticles of C(60), partially hydrolyzed aluminum phthalocyanine chloride (denoted as AlPc), and a composite of the two are reported. The three types of nanoparticles were obtained through a reprecipitation method from N-methyl-2-pyrrolidone solutions of C(60), aluminum phthalocyanine chloride (AlPcCl), and their mixture, respectively. The nanoparticle composite's ultraviolet-visible absorption, diffuse-reflectance and Fourier transform IR spectra, X-ray diffraction pattern, and scanning electron microscopy image are all similar to the sum of those of the C(60) and AlPc particles, respectively. The nano-ordered composite exhibits p/n junctionlike photoelectrochemical characteristics, which were investigated in comparison with those of vapor-deposited C(60) (n-type), AlPcCl (p-type), C(60)/AlPcCl (n/p), and AlPcCl/C(60) (p/n) electrodes. The nanoparticle composite further shows photocatalytic activity for the decomposition of trimethylamine to carbon dioxide in a suspension system.


Assuntos
Nanopartículas/química , Fotoquímica/métodos , Pontos Quânticos , Metilaminas/química
14.
ACS Appl Mater Interfaces ; 1(9): 1860-4, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20355806

RESUMO

Gold nanoparticles were supported by a phloroglucinolcarboxylic acid-formaldehyde (PF) gel, a new organic gel with a 30 nm spheroid-like structure. The surface area of the PF gel with gold nanoparticles was 550 m(2)/g. Gold nanoparticles supported on a PF gel exhibited catalytic activity in the reduction of 4-nitrophenol with a reaction rate constant of 7.4 x 10(-3) s(-1), which is high in the reported heterogeneous reaction system. The adsorption behavior of 4-nitrophenol into the gel support was observed by ultraviolet-visible absorption spectroscopy. Gold nanoparticles in the PF network were characterized by scanning electron microscopy, atomic force microscopy, and transmission electron microscopy observation. The high reduction rate would be attributed to the extraction and diffusion of the reactant through the pores of a PF gel support to encounter the highly dispersed gold nanoparticles on the surface and inside the material.


Assuntos
Ácidos Carboxílicos/química , Formaldeído/química , Ouro/química , Nanopartículas Metálicas/química , Floroglucinol/química , Polímeros/química , Catálise , Coloides/química , Géis , Cinética , Microscopia Eletrônica de Varredura/métodos , Microscopia Eletrônica de Transmissão/métodos , Modelos Químicos , Compostos Orgânicos/química , Raios Ultravioleta
16.
Phys Chem Chem Phys ; 10(11): 1562-8, 2008 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-18327312

RESUMO

Some types of phthalocyanines (MPc (M = H(2), Cu, or Zn), a p-type semiconductor) were used in combination with 3,4,9,10-perylenetetracarboxyl-bisbenzimidazole (PTCBI, an n-type semiconductor), with which those photoelectrode characteristics in the water phase were investigated in terms of kinetics. Each film of the PTCBI/MPc bilayer functioned as a photoanode, where the photoinduced oxidation of thiol occurs at the MPc/water interface along with the hole conduction through the MPc layer. The holes originate on account of the photophysical events in the p/n interior, involving the charge separation of excitons at the p/n interface. The typical photoelectrochemical characteristic in the PTCBI/MPc photoanodes involved a transient photocurrent occurring in the initial stage under illumination (under potentiostatic conditions): thereafter, it attained a steady state. Moreover, both the initial spiky photocurrents and the steady-state photocurrents exhibited saturation at higher concentrations. An analysis with photoelectrode kinetics was performed by assuming an adsorption step prior to a rate-limiting charge transfer step, where equations were applied to photocurrents based on the Langmuir adsorption equilibrium. The kinetic analyses evidently showed that the photoanodic reactions are kinetically dominated by the charge transfer between MPc and thiol, where the overall kinetics for thiol oxidation decreases in the following order: H(2)Pc > ZnPc > CuPc; that is, it appeared that H(2)Pc acts as the more efficient photofunctional interface capable of oxidation in the water phase when PTCBI was concurrently employed as an electron conductor. Considering that the photocurrent generated is proportional to the surface concentration of thiol (Gamma) at the MPc as well as the intrinsic oxidation rate (cf., ZnPc > H(2)Pc approximately CuPc), the higher efficiency in the output at the H(2)Pc surface was attributed to an exceptionally high Gamma (i.e., from the kinetic analyses, the Gamma value at the H(2)Pc surface was also inferred to be 2-3 times higher than that at the other MPcs). Through the present kinetic analysis, it also revealed that the activity for thiol oxidation taking place at Pc ring is comparable to that at the conventional active catalysts (i.e., polycarboxyphthalocyaninato Co(ii) and Fe(iii)) where a central metal is an active site.


Assuntos
Benzimidazóis/química , Indóis/química , Compostos Organometálicos/química , Perileno/química , Fotoquímica , Água/química , Cobre/química , Eletroquímica , Eletrodos , Hidrogênio/química , Isoindóis , Cinética , Oxirredução , Semicondutores , Análise Espectral , Compostos de Sulfidrila/química , Propriedades de Superfície , Zinco/química
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