RESUMEN
Carbon quantum dots (CQDs) derived from biomass, a suggested green approach for nanomaterial synthesis, often possess poor optical properties and have low photoluminescence quantum yield (PLQY). This study employed an environmentally friendly, cost-effective, continuous hydrothermal flow synthesis (CHFS) process to synthesise efficient nitrogen-doped carbon quantum dots (N-CQDs) from biomass precursors (glucose in the presence of ammonia). The concentrations of ammonia, as nitrogen dopant precursor, were varied to optimise the optical properties of CQDs. Optimised N-CQDs showed significant enhancement in fluorescence emission properties with a PLQY of 9.6% compared to pure glucose derived-CQDs (g-CQDs) without nitrogen doping which have PLQY of less than 1%. With stability over a pH range of pH 2 to pH 11, the N-CQDs showed excellent sensitivity as a nano-sensor for the highly toxic highly-pollutant chromium (VI), where efficient photoluminescence (PL) quenching was observed. The optimised nitrogen-doping process demonstrated effective and efficient tuning of the overall electronic structure of the N-CQDs resulting in enhanced optical properties and performance as a nano-sensor.
Asunto(s)
Puntos Cuánticos , Amoníaco , Carbono/química , Glucosa , Nitrógeno/química , Puntos Cuánticos/químicaRESUMEN
A short cut review was carried out to establish whether patients presenting to the emergency department after a near drowning should have cervical spine immobilisation. A search of the literature found only three studies directly relevant to the question. The author, date and country of publication, patient group studied, study type, relevant outcomes, results and study weaknesses of these papers are tabulated. The clinical bottom line is that cervical spine injuries are rare in drowning and near drowning unless there is a history of diving or a fall or signs of trauma. Cervical spine immobilisation should be reserved for cases where there is a reasonable suspicion of a spinal injury.
Asunto(s)
Vértebras Cervicales/lesiones , Medicina de Emergencia Basada en la Evidencia/normas , Ahogamiento Inminente/complicaciones , Restricción Física/normas , Traumatismos Vertebrales/prevención & control , Buceo/efectos adversos , Servicio de Urgencia en Hospital/normas , Medicina de Emergencia Basada en la Evidencia/instrumentación , Medicina de Emergencia Basada en la Evidencia/métodos , Humanos , Masculino , Selección de Paciente , Guías de Práctica Clínica como Asunto , Equipos de Seguridad , Restricción Física/instrumentación , Restricción Física/métodos , Traumatismos Vertebrales/diagnóstico , Traumatismos Vertebrales/etiología , Adulto JovenRESUMEN
A short cut review was carried out to establish whether patients presenting to the emergency department after a near drowning should have a CT head scan as part of their initial assessment. A search of the literature found only three studies directly relevant to the question. The author, date and country of publication, patient group studied, study type, relevant outcomes, results and study weaknesses of these papers are tabulated. The clinical bottom line is that anyone with GCS≤4 should have a CT head as an abnormal scan at this stage heralds a very poor prognosis.