Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 7 de 7
Filtrar
Mais filtros











Base de dados
Intervalo de ano de publicação
1.
Micromachines (Basel) ; 14(2)2023 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-36838191

RESUMO

With increasing consumption of energy and increasing environmental pollution, research on capturing the vibration energy lost during transportation and vehicle driving is growing rapidly. There is a large amount of vibration energy in the automobile exhaust system that can be recycled. This paper proposes a self-powered intelligent device (SPID) using a piezoelectric energy generator. The SPID includes a piezoelectric generator and sensor unit, and the generator is installed at the end of the automobile exhaust system. The generator adopts a parallel structure of four piezoelectric power generation units, and the sensing unit comprises light-emitting diode warning lights or low-power sensors. A simulated excitation experiment verifies the working state and peak power of the piezoelectric generator unit, which can achieve 23.4 µW peak power. The self-power supply and signal monitoring functions of the intelligent device are verified in experiments conducted for driving light-emitting diode lights and low-power sensors. The device is expected to play a crucial role in the field of intelligent driving and automobile intelligence.

2.
ACS Omega ; 7(27): 23315-23321, 2022 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-35847289

RESUMO

In this research, pyrolysis experiment of Indonesian oil sand was performed in a fixed bed. Results show that the temperature and heating rate had significant effects on the pyrolysis products. Data studied include yields of products and the gaseous product composition of carbon monoxide, hydrogen, methane, and other hydrocarbons. Four functional group bands (aromatic hydrocarbon, oxygen, aliphatic, and hydroxyl functional groups) are observed from Fourier transform infrared spectroscopy of oil sand. The influence of pyrolysis temperature on the total pore volume and the Brunauer-Emmett-Teller (BET) specific surface area of char was also studied. With increasing temperature, the BET specific surface area showed an increasing trend in the overall temperature range. The specific surface area and the total pore volume showed similar trends except the tiny difference of 5 °C/min from 200 to 300 °C. The heating rate did not influence the development of the pore structure obviously. Mainly, three different reaction regions were observed during pyrolysis of oil sand. This study provides a theoretical foundation for further effective exploitation and economical application of oil sand.

3.
Environ Sci Pollut Res Int ; 28(8): 9792-9805, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33156504

RESUMO

The co-combustion of sewage sludge and biomass is a key problem in coal-fired power plants. The combustion characteristics and pollutant emissions of municipal sewage sludge and biomass could result in unpredictable operation and environmental problems. In this study, the combustion experiments of corn stalk (CS), municipal sewage sludge (SS), and their blends were conducted in the thermogravimetric analyzer and muffle furnace, focusing on the combustion characteristics and the pollutants (SO2/NO) emissions with different temperature, proportion, and heating rate. It was found that the combustion characteristics of the mixture are affected by the mix ratio of SS. Compared with those of SS, the SO2 emission amount and S-SO2 conversion rate of CS are lower. The content of N in SS is higher than CS, but the conversion rate of N-NO is lower. Although the emissions of SO2 and NO from CS blending with SS are higher than those from CS combustion alone, the conversion rate of SO2 and NO decreases. This means that the co-combustion of CS and SS will reduce the content of pollutants released by CS combustion alone and effectively solve the environmental problems associated with CS incineration.


Assuntos
Poluentes Ambientais , Esgotos , Biomassa , Carvão Mineral/análise , Incineração , Zea mays
4.
J Phys Condens Matter ; 30(26): 265301, 2018 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-29762129

RESUMO

We study the electron transport properties through the junction of a benzene molecule in conjunction with two monolayer zigzag-edged phosphorene nanoribbon (ZPNR) electrodes by applying the nonequilibrium Green's functions in combination with the density functional theory. We find that the molecular junction with two phosphorus-carbon bonds exhibits an interesting low-bias negative differential resistance effect with a peak-to-valley ratio of 29, which originates from the edge states in ZPNR due to the anisotropic band structure of phosphorene. Importantly, the performance of the junction can be tuned via the molecule-ZPNR interface bonding. The findings may be useful in sensitive-device applications. Furthermore, the physical mechanisms are revealed and discussed in terms of the electronic transmission spectrum, the evolution of the frontier molecular orbitals, the local device density of states around the Fermi level, and the projected density of states.

5.
Breast Cancer ; 23(2): 216-23, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25098685

RESUMO

BACKGROUND: Telomerase, a ribonucleoprotein enzyme mainly consisted of a catalytic protein subunit human telomerase reverse transcriptase (hTERT) and a human telomerase RNA component, is responsible for maintaining telomeres. Telomerase over-expression correlates significantly with tumors and is a prognostic marker. However, telomerase over-expression in breast cancers and the effect of telomerase inhibition as a candidate cancer therapy are unknown. METHODS: We used the dominant-negative mutant of hTERT (DN-hTERT) to inhibit telomerase activity on human breast adenocarcinoma cell line MCF-7 by transfection. Telomeric repeat amplification protocol assays and real-time quantitative RT-PCR were performed to investigate telomerase activity as well as expression of hTERT. Telomere length was measured by the flow-fluorescence in situ hybridization assay. Cell proliferation was assessed by the WST-8 assay, and apoptosis was evaluated by flow cytometry. The tumor formation ability of MCF-7 cells was investigated by transplanting cells subcutaneously into BALB/c nude mice. RESULTS: Ectopic expression of DN-hTERT caused dramatically inhibition of telomerase activity and reduction of telomere length. Telomerase inhibition induced growth arrest and apoptosis of MCF7 cells in vitro and loss of tumorigenic properties in vivo. CONCLUSION: This study shows that telomerase inhibition by DN-hTERT can effectively inhibit the cell viability and tumorigenicity of MCF7 cells and is an attractive approach for breast cancer therapy.


Assuntos
Apoptose , Neoplasias da Mama/prevenção & controle , Proliferação de Células , Genes Dominantes , Telomerase/antagonistas & inibidores , Animais , Neoplasias da Mama/enzimologia , Neoplasias da Mama/patologia , Feminino , Citometria de Fluxo , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Telomerase/genética , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
6.
Cell Transplant ; 22 Suppl 1: S21-5, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23992752

RESUMO

The aim of the study was to analyze the clinical efficacy and safety of olfactory ensheathing cell (OEC) transplantation for treating patients with chronic, complete spinal cord injury (SCI). Six patients with six chronic complete spinal cord injuries were recruited and treated with autologous OEC transplantation and followed for 24 months. The scores from before and after transplantation were analyzed. This was a self-control experiment. There was significant amelioration in the scores of the standard neurological classification of spinal cord injury made by the America Spinal Cord Injury Association (ASIA) and the International Association of Neurorestoratology-Spinal Cord Injury Functional Rating Scale (IANR-SCIFRS) following OEC transplantation with 24 months of follow-up. No clinical complications were observed. OEC transplantation would appear to be clinically safe and may promote the neurofunctional recovery of SCI based on data from six patients. This manuscript is published as part of the International Association of Neurorestoratology (IANR) supplement issue of Cell Transplantation.


Assuntos
Transplante de Células/métodos , Mucosa Olfatória/citologia , Mucosa Olfatória/transplante , Traumatismos da Medula Espinal/terapia , Adulto , Técnicas de Cultura de Células , Doença Crônica , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mucosa Olfatória/cirurgia , Traumatismos da Medula Espinal/fisiopatologia , Sobreviventes
7.
J Int Med Res ; 41(2): 473-81, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23569013

RESUMO

OBJECTIVES: To investigate the safety and therapeutic efficacy of autologous olfactory ensheathing cell (OEC) transplantation in cervical spinal cord injury (SCI). METHODS: Patients with cervical SCI of >6 months' duration were treated with autologous OECs, injected into the area surrounding the SCI under magnetic resonance imaging guidance, twice a week for 4 weeks. Patients were evaluated before treatment and at 3, 6, 12 and 24 months post-treatment, using the American Spinal Injury Association (ASIA) Impairment Scale, the ASIA sensory and motor score and the Functional Independence Measure (FIM) score. RESULTS: Eight patients were recruited to the study. Three months after treatment, ASIA and FIM scores had improved significantly compared with pretreatment, though by 1 year no further significant improvements in the ASIA score were seen. The return of substantial sensation and motor activity in various muscles below the injury level was observed in three patients during follow-up. In addition, bladder function was restored in two patients. There were no serious complications postoperatively or during the follow-up period. CONCLUSIONS: This study provides preliminary evidence of the safety and possible efficacy of autologous OEC transplantation.


Assuntos
Mucosa Olfatória/citologia , Mucosa Olfatória/transplante , Traumatismos da Medula Espinal/terapia , Adolescente , Adulto , Vértebras Cervicais/patologia , Demografia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Transplante Autólogo , Adulto Jovem
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA