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1.
J Hazard Mater ; 472: 134311, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38691989

RESUMO

This study proposes a predictive model for assessing adsorber performance in gas purification processes, specifically targeting the removal of chemical warfare agents (CWAs) using breakthrough curve analysis. Conventional parameter estimation methods, such as Brunauer-Emmett-Teller analysis, encounter challenges due to the limited availability of kinetic and equilibrium data for CWAs. To overcome these challenges, we implement a Bayesian parametric inference method, facilitating direct parameter estimation from breakthrough curves. The model's efficacy is confirmed by applying it to H2S purification in a fixed-bed setup, where predicted breakthrough curves aligned closely with previous experimental and numerical studies. Furthermore, the model is applied to sarin with ASZM-TEDA carbon, estimating key parameters that could not be assessed through conventional experimental techniques. The reconstructed breakthrough curves closely match actual measurements, highlighting the model's accuracy and robustness. This study not only enhances filter performance prediction for CWAs but also offers a streamlined approach for evaluating gas purification technologies under limited experimental data conditions.

2.
Vet Med Sci ; 9(5): 1959-1964, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37515576

RESUMO

A 6-year-old neutered male Siamese cat was referred for investigation of hindlimb ataxia and blindness of 2 weeks' duration. A swollen right hind limb, with no history of trauma, and no evidence of an external wound, was observed on physical examination. Ophthalmic examination revealed bilateral absence of the menace response and changes consistent with uveitis. Blood tests identified changes consistent with inflammation including serum amyloid A elevation. Infectious disease testing was negative. Degenerate neutrophils and bacterial cocci were detected on fine needle aspiration cytology of the affected limb. Thoracic radiography and abdominal ultrasonography identified no abnormalities. Primary pyomyositis was suspected and clindamycin was prescribed following Penrose drain tube placement. In addition, eye drops containing tobramycin, atropine, and prednisolone were administered. The clinical signs and serum amyloid A level were markedly improved after 5 days of treatment. Based on the medical history and lack of other findings, the uveitis was suspected to be secondary to the pyomyositis. The clinical signs resolved completely, and no recurrence was reported within a 6-month follow-up period. To the best of our knowledge, primary pyomyositis with uveitis has not been previously reported in cats.


Assuntos
Doenças do Gato , Piomiosite , Uveíte , Gatos , Masculino , Animais , Piomiosite/diagnóstico , Piomiosite/tratamento farmacológico , Piomiosite/veterinária , Proteína Amiloide A Sérica , Uveíte/diagnóstico , Uveíte/tratamento farmacológico , Uveíte/veterinária , Doenças do Gato/diagnóstico por imagem , Doenças do Gato/tratamento farmacológico
3.
Vet Sci ; 10(7)2023 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-37505843

RESUMO

An 8-year-old, castrated male Shih-tzu dog (Case 1) showing ataxia and gait disorder was referred for neurological examination and magnetic resonance imaging. Through comprehensive examinations, the patient was tentatively diagnosed with meningoencephalitis of unknown origin (MUO) and treatment with prednisolone and cytosine arabinoside was started. The symptoms were improving with immunosuppressive treatment. However, severe bacterial cystitis occurred and we could not avoid tapering off prednisolone. Then, neurological signs recurred. Therefore, we added crisdesalazine, which allowed us to reduce the daily dosage of immunosuppressants easily. In another case, a 4-year-old, spayed female Yorkshire terrier dog (Case 2) was referred to our hospital showing a head tilt, circling, and loss of the menace reflex. The patient was tentatively diagnosed with MUO and treatment with some immunosuppressants was attempted. The clinical symptoms improved, but the alleviation was inadequate. Thus, we added crisdesalazine. The neurological signs then markedly improved. Moreover, the drugs could be tapered off more easily than before. Crisdesalazine is a novel drug that has antioxidant and anti-inflammatory action in brain disease and is used particularly for dementia. In this paper, we tried an off-label use of this drug in canine MUO patients, and found that it had, in these two patients, additional therapeutic effects on the MUO.

4.
Vet Sci ; 10(6)2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-37368771

RESUMO

A 12-year-old spayed female domestic short cat was presented with tetraplegia. The cat also showed signs of hyponatremia and dehydration, which were rapidly corrected by intravenous fluid infusion. Based on thorough physical and neurological examinations, the patient was suspected of having an intracranial disease. MRI revealed a high-signal T2 image of the bilateral parietal cerebral cortical gray matter junction, which is associated with fast electrolyte calibration, and a high-signal T2 image of the C2 spinal cord ventral area, which is associated with ischemic myelopathy. The cat reappeared three days later due to anorexia. Laboratory examinations revealed that the cat was clinically dehydrated and exhibited hyponatremia. Other causes of hyponatremia were excluded through history-taking, laboratory examination, imaging, and therapeutic response to fluid therapy, except for cerebral salt-wasting syndrome (CSWS). The cat was discharged 3 days after the start of fludrocortisone therapy with electrolytes within the normal range. Magnetic resonance imaging (MRI) was performed again 1 month after hospitalization, and the cerebral lesion disappeared, but the spinal cord lesion worsened compared to the previous image. The patient was euthanized due to the progression of the spinal lesion, with a poor prognosis and poor quality of life. This is the first case of suspected CSWS with a cervical spinal lesion in a cat.

5.
ACS Appl Mater Interfaces ; 14(28): 32522-32532, 2022 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-35793246

RESUMO

With the growing interest in chemical and biological warfare agents (CWAs/BWAs), the focus has shifted toward aerosol protection using protective clothing. However, compared to air-permeable membranes, those with water vapor permeability have been investigated more extensively. Filtering membranes without air permeability have limited practical usage in personal protective suits and masks. In this study, polyacrylonitrile membranes with tightly attached activated carbon and doped copper(II) oxide were prepared via electrospinning. The nanofibers with uniformly controlled diameters and smooth morphologies enable water/air breathability and protection against aerosol (100 nm polystyrene nanobeads similar to SARS-CoV-2) penetration. The uniformly distributed and tightly attached activated carbon and doped copper(II) oxide particles enhance the sorptive performance of the membranes by blocking gaseous CWAs, including soman, nerve chemical agents, and BWAs. Such dual-purpose membranes can be implemented in protective equipment owing to their high performance and easy processing.


Assuntos
COVID-19 , Carvão Vegetal , Aerossóis , COVID-19/prevenção & controle , Cobre , Humanos , Permeabilidade , SARS-CoV-2
6.
Molecules ; 26(13)2021 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-34201878

RESUMO

Composites of metal-organic frameworks and carbon materials have been suggested to be effective materials for the decomposition of chemical warfare agents. In this study, we synthesized UiO-66-NH2/zeolite-templated carbon (ZTC) composites for the adsorption and decomposition of the nerve agents sarin and soman. UiO-66-NH2/ZTC composites with good dispersion were prepared via a solvothermal method. Characterization studies showed that the composites had higher specific surface areas than pristine UiO-66-NH2, with broad pore size distributions centered at 1-2 nm. Owing to their porous nature, the UiO-66-NH2/ZTC composites could adsorb more water at 80% relative humidity. Among the UiO-66-NH2/ZTC composites, U0.8Z0.2 showed the best degradation performance. Characterization and gas adsorption studies revealed that beta-ZTC in U0.8Z0.2 provided additional adsorption and degradation sites for nerve agents. Among the investigated materials, including the pristine materials, U0.8Z0.2 also exhibited the best protection performance against the nerve agents. These results demonstrate that U0.8Z0.2 has the optimal composition for exploiting the degradation performance of pristine UiO-66-NH2 and the adsorption performance of pristine beta-ZTC.


Assuntos
Carbono/química , Estruturas Metalorgânicas/química , Agentes Neurotóxicos/química , Compostos Organometálicos/química , Ácidos Ftálicos/química , Zeolitas/química , Adsorção , Estruturas Metalorgânicas/síntese química , Estruturas Metalorgânicas/ultraestrutura , Microscopia Eletrônica de Varredura , Porosidade , Sarina/química , Soman/química , Espectroscopia de Infravermelho com Transformada de Fourier , Água/química , Difração de Raios X
7.
J Hazard Mater ; 417: 125904, 2021 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-33975167

RESUMO

The development of efficient adsorbents to remove radioactive methyl iodide (CH3I) in humid environments is crucial for air purification after pollution by nuclear power plant waste. In this work, we successfully prepared a post-synthetic covalent modified MIL-101 with a sulfonate group followed by the ion-exchange of Ag (I), which is well characterized by diffuse reflectance FT-IR spectroscopy, X-ray photoelectron spectroscopy (XPS) and the hydrophobic index (HI). After modification of the MOFs, we applied functionalized MIL-101 obtained by either one-pot synthesis (MIL-101-SO3Ag) or a post-synthetic modification process (MIL-101-RSO3Ag, R = NH(CH2)3) to remove the CH3I at an extremely low concentration (0.31 ppm) in an environment with very high relative humidity (RH 95%). Enhanced hydrophobicity of the surface-modified MIL-101 was evaluated by examining the HI with the competitive adsorption of water and cyclohexane vapor, with a high surface area maintained, as confirmed by Ar physisorption. Interestingly, the post-synthetically modified MIL-101-RSO3Ag showed exceptional adsorption performance as determined by its decontamination factor (DF = 195,350) at 303 K and RH 95%. This performance was in comparison to Ag (I)-exchanged 13X zeolite and MIL-101-SO3Ag, which include much higher amounts of Ag. Furthermore, MIL-101-RSO3Ag retained ~94-100% of its fresh adsorbent performance during five cycle repetitions.


Assuntos
Cromo , Poluentes Químicos da Água , Hidrocarbonetos Iodados , Ácidos Ftálicos , Prata , Espectroscopia de Infravermelho com Transformada de Fourier , Poluentes Químicos da Água/análise
8.
Nanoscale ; 12(28): 15214-15221, 2020 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-32639495

RESUMO

Micro/meso-porous Bi@C nanoplates are synthesized by pyrolyzing Bi-based metal-organic frameworks (MOFs) prepared by a microwave-assisted hydrothermal method to overcome huge volume expansion and pulverization of anode materials during battery operation. The Bi@C nanoplates are composed of ∼10-50 nm Bi nanoparticles in an amorphous carbon shell. The material shows very high capacity (556 mA h g-1) after 100 cycles at 100 mA g-1 and good cycling performance. Moreover, the Bi@C nanoplates perform well at high current densities and have excellent cyclic stability; their capacity is 308 mA h g-1 after 50 cycles and 200 mA h g-1 after 1000 cycles at 3000 mA g-1. The outstanding performance of this anode is due to the nanosized Bi and amorphous carbon shell. The nanosized Bi reduces the diffusion length of Li ions, while the amorphous carbon shell improves the electrical conductivity of the anode and also restrains the pulverization and aggregation of the metal during cycling. The proposed hierarchical micro/meso-porous materials derived from MOFs are a new type of nanostructures that can aid the development of novel Bi-based anodes for LIBs.

9.
Materials (Basel) ; 13(13)2020 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-32630315

RESUMO

Zirconium hydroxide, Zr(OH)4 is known to be highly effective for the degradation of chemical nerve agents. Due to the strong interaction force between Zr(OH)4 and the adsorbed water, however, Zr(OH)4 rapidly loses its activity for nerve agents under high-humidity environments, limiting real-world applications. Here, we report a nanocomposite material of Zr(OH)4 and graphene oxide (GO) which showed enhanced stability in humid environments. Zr(OH)4/GO nanocomposite was prepared via a dropwise method, resulting in a well-dispersed and embedded GO in Zr(OH)4 nanocomposite. The nitrogen (N2) isotherm analysis showed that the pore structure of Zr(OH)4/GO nanocomposite is heterogeneous, and its meso-porosity increased from 0.050 to 0.251 cm3/g, compared with pristine Zr(OH)4 prepared. Notably, the composite material showed a better performance for nerve agent soman (GD) degradation hydrolysis under high-humidity air conditions (80% relative humidity) and even in aqueous solution. The soman (GD) degradation by the nanocomposite follows the catalytic reaction with a first-order half-life of 60 min. Water adsorption isotherm analysis and diffuse reflectance infrared Fourier transform (DRIFT) spectra provide direct evidence that the interaction between Zr(OH)4 and the adsorbed water is reduced in Zr(OH)4/GO nanocomposite, indicating that the active sites of Zr(OH)4 for the soman (GD) degradation, such as surface hydroxyl groups are almost available even in high-humidity environments.

10.
J Colloid Interface Sci ; 563: 363-369, 2020 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-31887700

RESUMO

HYPOTHESIS: The development of clothing that protects soldiers in the battlefield against wetting and chemical/biological (CB) warfare agents is of utmost importance. There are many examples in nature where the structures of some surfaces render them resistant to particular liquids. Hence, it should be possible to prepare an omniphobic textile surface that repels both water and liquid chemical warfare agents by combining a zirconium (Zr)-based porous metal-organic framework (MOF) or metal oxide and a polyhedral oligomeric silsesquioxane (POSS) to control the surface structure. EXPERIMENTS: Hierarchical micro/nanostructures were generated on a textile surface by growing UiO-66-NH2 or Zr(OH)4 on cotton fabric. This was followed by a coating of a hydrophobic aminopropylisooctyl polyhedral oligomeric silsesquioxane (O-POSS) on the surface of the textile. FINDINGS: UiO-66-NH2 or Zr(OH)4 particles were well grown on the surface of the cotton fabric with micro/nano surface structures. Less than a monolayer coating of O-POSS preserved the surface feature of UiO-66-NH2 or Zr(OH)4. The O-POSS coated UiO-66-NH2 on cotton fabric thus formed exhibited resistance towards wetting with water and the chemical warfare agent, sulfur mustard (HD). The static contact angles are >150° for a 5 µL water droplet and 107° for a 3 µL HD droplet. The roll-off angle is 7° for a 50 µL water droplet. Thus, this method may provide fabric developers (military or ordinary) with strategies to design and fabricate better omniphobic fabrics with optimal liquid-repellent properties.

11.
ACS Appl Mater Interfaces ; 10(47): 40651-40660, 2018 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-30375849

RESUMO

Sulfur mustard gas, also called HD, is one of the main chemical warfare agents and has claimed thousands of lives and left many more contaminated. The development of functional materials to promptly capture and detoxify sulfur mustard within a few minutes is extremely important to save the lives of the affected people. This has motivated us to explore excellent detoxification systems that can be deployed in the field to rapidly capture and hydrolyze mustard gas in a short time. To that end, we present a silver-ion-exchanged zeolite Y [(Ag+) n@Y, n = 5, 13, 21, 32, 43, and 55] that can rapidly capture mustard gas and its simulant (2-chloroethyl ethyl sulfide, CEES) in ambient conditions to enable the prompt hydrolysis of the CEES captured in its nanopores. The capture and hydrolysis ability of Ag+@Y positively correlated with its number of Ag+ ions. In addition, 70% of CEES (2.5 µL in 1 mL) was captured by (Ag+)55@Y within 20 min at 25 °C in ambient conditions. Moreover, 100% CEES (2.5 µL in 1 mL aqueous ethanol cosolvent) was hydrolyzed in 1 min at 25 °C. The efficiency of Ag+@Y in capturing and hydrolyzing CEES as well as mustard gas is thus a system with high detoxification efficiency for this dangerous chemical warfare agent.

12.
RSC Adv ; 8(72): 41633-41638, 2018 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-35559276

RESUMO

Herein, cotton fabric was treated with an alkaline solution to increase the content of surface hydroxyl groups and then functionalized with UiO-66-NH2, a nanoporous metal-organic framework. Instrumental analysis of the thus treated fabric revealed that its surface was covered with UiO-66-NH2 crystals in a uniform manner. The ability of the functionalized fabric to degrade two chemical warfare agents (soman and sulfur mustard) was probed by testing its permeability to these two agents (swatch testing), and the excellent degradation performance was concluded to be well suited for a broad range of filtration and decontamination applications.

13.
Chem Commun (Camb) ; 52(79): 11775-11778, 2016 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-27722313

RESUMO

A bismuth oxide electrode, delivering high capacity, as an anode material for sodium-ion batteries was simply prepared. The electrochemical properties of bismuth oxide were studied by operando X-ray absorption near edge structure spectroscopy and ex situ X-ray diffraction methods. A bismuth oxide/carbon composite showed enhanced cycle stability at high current densities.

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