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1.
Soft Matter ; 17(32): 7498-7505, 2021 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-34338275

RESUMO

Magneto-active polymers (MAPs) can undergo rapid and noticeable deformation through external wireless magnetic stimulation, offering a possibility to develop potential applications such as in actuators, flexible micro-grippers, soft robots, etc. In this paper, a theoretical model is presented to depict the relationship between nonlinear deformation and the external mechanical load applied on cylindrical samples in the presence of magnetic fields generated by an electromagnet. The geometrical and electromagnetic properties of the electromagnet are explicitly modeled in COMSOL Multiphysics based on the measured data. Furthermore, a finite element model is constructed to obtain detailed information (such as strain field), which cannot be obtained in experiments. The theoretical and simulation results fit quite well with the experimental results, showing the accuracy of the model construction. The proposed designing approach and model provide guidelines for researchers to enrich the applications of MAPs.

2.
Chemosphere ; 235: 163-168, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31255756

RESUMO

Two novel phosphorus-containing copolyesters were synthesized by direct polycondensation reaction of phenyl dichlorophosphate, 1,4-succinic acid and 1,4-butanediol using stannous chloride (SnCl2) and 4-Methylbenzenesulfonic acid as catalyst, and its chemical structures were identified by 1H and 31P nuclear magnetic resonances (1H and 31P NMR). The resulting phosphorus-containing poly(butylene succinate) (PPBS) was characterized by X-ray diffraction (XRD), polarized optical microscope (POM), thermogravimetry analysis (TGA) and differential scanning calorimetry (DSC). PPBS can be as a flame retardant for commercial poly(butylene succinate) (PBS). A series of flame retardant composite materials were produced by melt-blending of PBS and PPBS. The comprehensive flame retardant property of composite materials was evaluated by limited oxygen index (LOI). While 20 wt % of PPBS was added into PBS resin, good flame retardant properties could be obtained. Composite materials can have much better flame retardancy (LOI = 30) than neat PBS resin. Thermogravimetric analysis (TGA) showed that the weight loss of PBS was decreased by the introduction of PPBS. In addition, possible flame retardancy mechanism of PPBS in composite materials was analyzed by SEM photos of char residue.


Assuntos
Butileno Glicóis/química , Butileno Glicóis/síntese química , Retardadores de Chama/síntese química , Poliésteres/química , Polímeros/química , Polímeros/síntese química , Varredura Diferencial de Calorimetria , Retardadores de Chama/análise , Espectroscopia de Ressonância Magnética , Fósforo , Poliésteres/síntese química , Termogravimetria , Difração de Raios X
3.
ACS Appl Mater Interfaces ; 10(29): 24758-24766, 2018 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-29968470

RESUMO

Soft display has been intensively studied in recent years in the wake of rapid development of a variety of soft materials. The currently existing solutions for translating the traditional hard display into the more convenient soft display mainly include light-emitting diodes, liquid crystals, quantum dots, and phosphors. The desired soft display should take the advantages of facile fabrication processes and cheap raw materials. Besides, the device should be colorful, nontoxic, and not only flexible but also stretchable. However, the foregoing devices may not own all of the desired features. Here, a new type of soft display, which consists of dielectric elastomer and photonic crystals that cover all of the features mentioned above and can achieve the color change dynamically and in situ, is reported. In addition to the above features, the angle-dependent characteristic and the excellent mechanical reliability make it a great candidate for the next generation of soft display. Finally, the vast applications of the present concept in a variety of fields are also prospected.

4.
Lancet Glob Health ; 6(5): e555-e567, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29653628

RESUMO

BACKGROUND: From 2003 to 2005, standardised 5-year cancer survival in China was much lower than in developed countries and varied substantially by geographical area. Monitoring population-level cancer survival is crucial to the understanding of the overall effectiveness of cancer care. We therefore aimed to investigate survival statistics for people with cancer in China between 2003 and 2015. METHODS: We used population-based data from 17 cancer registries in China. Data for the study population was submitted by the end of July 31, 2016, with follow-up data on vital status obtained on Dec 31, 2015. We used anonymised, individual cancer registration records of patients (aged 0-99 years) diagnosed with primary, invasive cancers from 2003 to 2013. Patients eligible for inclusion had data for demographic characteristics, date of diagnosis, anatomical site, morphology, behaviour code, vital status, and last date of contact. We analysed 5-year relative survival by sex, age, and geographical area, for all cancers combined and 26 different cancer types, between 2003 and 2015. We stratified survival estimates by calendar period (2003-05, 2006-08, 2009-11, and 2012-15). FINDINGS: There were 678 842 records of patients with invasive cancer who were diagnosed between 2003 and 2013. Of these records, 659 732 (97·2%) were eligible for inclusion in the final analyses. From 2003-05 to 2012-15, age-standardised 5-year relative survival increased substantially for all cancers combined, for both male and female patients, from 30·9% (95% CI 30·6-31·2) to 40·5% (40·3-40·7). Age-standardised 5-year relative survival also increased for most cancer types, including cancers of the uterus (average change per calendar period 5·5% [95% CI 2·5-8·5]), thyroid (5·4% [3·2-7·6]), cervix (4·5% [2·9-6·2]), and bone (3·2% [2·1-4·4]). In 2012-15, age-standardised 5-year survival for all patients with cancer was higher in urban areas (46·7%, 95% CI 46·5-47·0) than in rural areas (33·6%, 33·3-33·9), except for patients with oesophageal or cervical cancer; but improvements in survival were greater for patients residing in rural areas than in urban areas. Relative survival decreased with increasing age. The increasing trends in survival were consistent with the upward trends of medical expenditure of the country during the period studied. INTERPRETATION: There was a marked overall increase in cancer survival from 2003 to 2015 in the population covered by these cancer registries in China, possibly reflecting advances in the quality of cancer care in these areas. The survival gap between urban and rural areas narrowed over time, although geographical differences in cancer survival remained. Insight into these trends will help prioritise areas that need increased cancer care. FUNDING: National Key R&D Program of China, PUMC Youth Fund and the Fundamental Research Funds for the Central Universities, and Major State Basic Innovation Program of the Chinese Academy of Medical Sciences.


Assuntos
Sobreviventes de Câncer/estatística & dados numéricos , Neoplasias/mortalidade , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , China/epidemiologia , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Sistema de Registros , Taxa de Sobrevida/tendências , Adulto Jovem
5.
Chem Commun (Camb) ; (14): 1660-1, 2004 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-15263967

RESUMO

Amorphous mesoporous aluminophosphate materials synthesized from precursors of Al(NO3)3/H3PO4/NH4OH in the presence of citric acid, exhibit high specific surface areas, narrow pore size distributions and excellent thermal stabilities.

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