Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 5 de 5
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
J Am Chem Soc ; 146(8): 5605-5613, 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38351743

RESUMO

Carbonyl is highly accessible and acts as an essential functional group in chemical synthesis. However, the direct catalytic deoxygenative functionalization of carbonyl compounds via a putative metal carbene intermediate is a formidable challenge due to the requirement of a high activation energy for the cleavage of strong C═O double bonds. Here, we report a class of bench stable and readily available Cp*Mo(II)-complexes as efficient deoxygenation catalysts that could catalyze the direct intermolecular deoxygenative coupling of carbonyl compounds with alkynes. Enabled by this powerful Cp*Mo(II)-catalyst, various valuable heteroarenes (10 different classes) were obtained in generally good yields and remarkable chemo- and regioselectivities. Mechanistic studies suggested that this reaction might proceed via a sequence of C═O double bonds cleavage, carbene-alkyne metathesis, cyclization, and aromatization processes. This strategy not only provided a general catalytic platform for the rapid preparation of heteroarenes but also opened a new window for the applications of Cp*Mo(II)-catalysts in organic synthesis.

2.
Polymers (Basel) ; 12(11)2020 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-33114103

RESUMO

Three-dimensional (3D) printing is a manufacturing technology which creates three-dimensional objects layer-by-layer or drop-by-drop with minimal material waste. Despite the fact that 3D printing is a versatile and adaptable process and has advantages in establishing complex and net-shaped structures over conventional manufacturing methods, the challenge remains in identifying the optimal parameters for the 3D printing process. This study investigated the influence of processing parameters on the mechanical properties of Fused Deposition Modelling (FDM)-printed carbon fiber-filled polylactide (CFR-PLA) composites by employing an orthogonal array model. After printing, the tensile and impact strengths of the printed composites were measured, and the effects of different parameters on these strengths were examined. The experimental results indicate that 3D-printed CFR-PLA showed a rougher surface morphology than virgin PLA. For the variables selected in this analysis, bed temperature was identified as the most influential parameter on the tensile strength of CFR-PLA-printed parts, while bed temperature and print orientation were the key parameters affecting the impact strengths of printed composites. The 45° orientation printed parts also showed superior mechanical strengths than the 90° printed parts.

3.
Annu Int Conf IEEE Eng Med Biol Soc ; 2019: 3147-3150, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31946555

RESUMO

In this paper, we aimed to evaluate the relationship between walking and emotion. We utilized the two-dimension (2D) walking condition map and the 2D emotion map to confirm the tendency and correlation. From the results, we defined each walking gait corresponding to each emotional state. To valid use walking-emotion relationship, we proposed to use it as a new evaluation method combined with the assistive walking device. Thus, the patient can acquire an improved rehabilitation effect while using the assistive walking device. To significantly use this method, we suggested that the patient walks by following the personal walking limitation region. Therefore, they can control the emotion via the proposed evaluation method. By connecting two maps, the interaction maps were proposed. Finally, the proposed evaluation results can provide a valuable application for various assistive devices to maintain the motivation of the user while performing the rehabilitation. Two-way control (emotion controls walking and walking controls emotion) would be applied to the assistive walking device in future works.


Assuntos
Equipamentos Ortopédicos , Tecnologia Assistiva , Caminhada , Emoções , Marcha , Humanos
5.
Zhonghua Wei Chang Wai Ke Za Zhi ; 16(9): 835-7, 2013 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-24061988

RESUMO

OBJECTIVE: To explore the characteristics of lymph node metastasis in thoracic esophageal cancer in order to provide evidence for the extent of lymph node dissection and the operation access. METHODS: A retrospective study was performed on the specimens of 72 patients who underwent radical operation of right transthoracic approach and the features of lymph node metastasis were explored. RESULTS: Lymph node metastases were found in 48 of 72 patients (66.7%). In 1495 lymph nodes dissected, metastases was identified in 181 lymph nodes (12.1%). The rate of lymph node metastasis in the right and left recurrent laryngeal nerve was 30.6% and 12.5% respectively. Lymph node metastasis was associated with tumor size and tumor invasion depth (both P<0.05), while tumor location and differentiation of tumor cells were not significant (both P>0.05). CONCLUSIONS: The lymph node metastasis in thoracic esophageal carcinoma can be easily found in the right recurrent laryngeal nerve. The best surgical approach of thoracic esophageal carcinoma is the right transthoracic approach.


Assuntos
Neoplasias Esofágicas/patologia , Metástase Linfática/patologia , Adulto , Idoso , Neoplasias Esofágicas/cirurgia , Feminino , Humanos , Excisão de Linfonodo , Linfonodos/patologia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...