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1.
Nat Commun ; 12(1): 5008, 2021 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-34429436

RESUMO

Capabilities for continuous monitoring of pressures and temperatures at critical skin interfaces can help to guide care strategies that minimize the potential for pressure injuries in hospitalized patients or in individuals confined to the bed. This paper introduces a soft, skin-mountable class of sensor system for this purpose. The design includes a pressure-responsive element based on membrane deflection and a battery-free, wireless mode of operation capable of multi-site measurements at strategic locations across the body. Such devices yield continuous, simultaneous readings of pressure and temperature in a sequential readout scheme from a pair of primary antennas mounted under the bedding and connected to a wireless reader and a multiplexer located at the bedside. Experimental evaluation of the sensor and the complete system includes benchtop measurements and numerical simulations of the key features. Clinical trials involving two hemiplegic patients and a tetraplegic patient demonstrate the feasibility, functionality and long-term stability of this technology in operating hospital settings.


Assuntos
Técnicas Biossensoriais/métodos , Fontes de Energia Elétrica , Pressão , Temperatura , Tecnologia sem Fio , Adulto , Idoso , Idoso de 80 Anos ou mais , Técnicas Biossensoriais/instrumentação , Desenho de Equipamento , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Monitorização Fisiológica , Pele , Termografia/instrumentação , Termografia/métodos
2.
Medicina (Kaunas) ; 57(7)2021 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-34209501

RESUMO

Background and objectives: Obstructive sleep apnea (OSA) is closely associated with insulin resistance (IR) and is an independent risk factor for incident type 2 diabetes mellitus (T2DM). Most studies evaluate the correlation between OSA and IR in only obese or T2DM patients. Therefore, we tried to investigate the effect of OSA on metabolic syndrome and IR in the general healthy male population. Materials and Methods: 184 subjects who visited a preventive health examination program were recruited for this study. All subjects received overnight polysomnography by a portable device (Watch-PAT 200). We examined several metabolic parameters and a homeostasis model of assessment for insulin resistance index (HOMA-IR). The subjects were divided into three groups by AHI (Apnea-hyponea index): normal group (AHI < 5), mild OSA group (5 ≤ AHI < 15), and moderate-severe OSA group (AHI ≥ 15). They were also divided into two groups according to minimum oxygen saturation: low group, Min-SpO2 < 88%; and high group, Min-SpO2 ≥ 88%. Results: Parameters of metabolic syndrome, including waist circumference, systolic and diastolic blood pressure, triglyceride, and high-density lipoprotein cholesterol showed significant differences among the AHI groups. Furthermore, HOMA-IR showed significant differences among the AHI groups. Those parameters, including metabolic syndrome and HOMA-IR, also showed differences between Min-SpO2 groups. Conclusions: In summary, this study helps confirm that AHI is associated with HOMA-IR in the general male population. Furthermore, the severity of AHI correlated with the parameters of metabolic syndrome. Therefore, AHI might be an indicator for evaluating both T2DM and metabolic syndrome, even in the general male population.


Assuntos
Diabetes Mellitus Tipo 2 , Resistência à Insulina , Síndrome Metabólica , Glicemia , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/epidemiologia , Humanos , Hipóxia/epidemiologia , Masculino , Síndrome Metabólica/complicações , Síndrome Metabólica/epidemiologia
3.
Nat Neurosci ; 24(7): 1035-1045, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33972800

RESUMO

Advanced technologies for controlled delivery of light to targeted locations in biological tissues are essential to neuroscience research that applies optogenetics in animal models. Fully implantable, miniaturized devices with wireless control and power-harvesting strategies offer an appealing set of attributes in this context, particularly for studies that are incompatible with conventional fiber-optic approaches or battery-powered head stages. Limited programmable control and narrow options in illumination profiles constrain the use of existing devices. The results reported here overcome these drawbacks via two platforms, both with real-time user programmability over multiple independent light sources, in head-mounted and back-mounted designs. Engineering studies of the optoelectronic and thermal properties of these systems define their capabilities and key design considerations. Neuroscience applications demonstrate that induction of interbrain neuronal synchrony in the medial prefrontal cortex shapes social interaction within groups of mice, highlighting the power of real-time subject-specific programmability of the wireless optogenetic platforms introduced here.


Assuntos
Optogenética/instrumentação , Comportamento Social , Tecnologia sem Fio/instrumentação , Animais , Camundongos
4.
Otol Neurotol ; 41(10): e1231-e1236, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32810014

RESUMO

OBJECTIVE: To identify differences in the vestibulo-ocular reflex (VOR) gain value and the peak saccade velocity in the suppression video head impulse test paradigms according to the age of the subject and the direction of the impulse. STUDY DESIGN: Retrospective chart analysis. SETTING: Tertiary referral hospital. PATIENTS/INTERVENTIONS: Between October 2017 and May 2019, we enrolled subjects who had previous histories of dizziness but no dizziness over the last 1 month. MAIN OUTCOME MEASURE: We conducted cervical vestibular-evoked myogenic potential and caloric tests, as well as video head impulse tests. We excluded the subjects who had abnormal cervical vestibular-evoked myogenic potential results (asymmetry ratio of greater than 30%) and abnormal caloric test results (caloric paresis of greater than 25%). RESULTS: We included 647 subjects aged 10 to 87 years. The mean VOR gain and peak saccade velocity were maintained in subjects less than 70 years old (VOR gain, 0.991 ±â€Š0.08, peak saccade velocity, 348.47 ±â€Š142.32). However, the decreases in VOR gain and peak saccade velocity were significant in subjects over 70 years old (VOR gain, 0.928 ±â€Š0.09, peak saccade velocity, 315.51 ±â€Š0.09; p < 0.001). The mean VOR gain of the rightward impulse (1.00 ±â€Š0.09) was higher than the leftward impulse (0.96 ±â€Š0.08, p < 0.001). CONCLUSIONS: Both the VOR gain and peak saccade velocity of suppression video head impulse test paradigms declined with increasing age over 70 years. In addition, the VOR gain of the rightward impulse was higher than the leftward impulse in the right-eye recordings.


Assuntos
Teste do Impulso da Cabeça , Reflexo Vestíbulo-Ocular , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Envelhecimento , Testes Calóricos , Criança , Humanos , Pessoa de Meia-Idade , Estudos Retrospectivos , Adulto Jovem
5.
J Vestib Res ; 30(3): 203-212, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32623411

RESUMO

BACKGROUND: A considerable number of patients with sudden sensorineural hearing loss (SSNHL) have been reported to have dizziness. OBJECTIVE: To analyze vestibular functions and identify the clinical characteristics of SSNHL with dizzinessMETHODS:71 patients with SSNHL who complained of dizziness were investigated retrospectively. The patients underwent vestibular function tests consisting of video-nystagmography, video head impulse test and vestibular evoked myogenic potentials. RESULTS: Among 35 patients with spontaneous nystagmus (SN), 21 showed ipsilesional posterior canal gain deficit, 11 showed a gain deficit in the posterior canal only and 9 showed both horizontal and posterior canal gain deficit in video head impulse test. In only one subject with bilateral horizontal canal gain deficit with contralesional SN, AICA infarction was observed.Among 36 patients without SN, 10 were diagnosed as benign paroxysmal positional vertigo and 5 had ipsilesional canal paresis in caloric test. Other 21 patients showed no abnormal signs in vestibular function tests. CONCLUSIONS: In VFT analysis of SSNHL with dizziness, diverse patterns were identified. In the absence of SN, no definite vestibular organ involvement was the most frequent. But in the case with SN, posterior canal deficit was most common and cerebellar ischemic stroke was rare.

6.
Otol Neurotol ; 41(7): 964-971, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32658401

RESUMO

OBJECTIVE: To examine the importance of video head impulse test parameter for recovery of symptoms in acute vestibular neuritis (AVN). STUDY DESIGN: Prospective study. SETTING: Tertiary referral hospital. PATIENTS/INTERVENTIONS: Twenty-seven patients with AVN were enrolled. We divided patients into two groups according to both dizziness handicap inventory (DHI) score and visual analog scale (VAS) at 6 months: Group F (symptoms free), DHI = 0 and VAS = 0; Group R (symptoms residual), DHI more than zero or VAS more than zero. MAIN OUTCOME MEASURE: All patients underwent video head impulse test paradigm (HIMP), and suppression head impulse test paradigm (SHIMP) initially and at 1 month. Patients were also asked to complete DHI and VAS initially, at 1 month and 6 months. We compared measured parameters between Group F and R. RESULTS: In HIMP, Group F showed higher vestibular-ocular reflex (VOR) gain, higher occurrence of covert corrective saccade (CS), lower occurrence and peak velocity of overt CS, and lower PR score than Group R at 1 month. In SHIMP, Group F showed higher VOR gain, higher occurrence and peak velocity of anti-CS, and higher PR score than Group R at 1 month. CONCLUSIONS: Above parameters of both HIMP and SHIMP at 1 month would be important factors to predict the residual symptoms in chronic phase of AVN.


Assuntos
Teste do Impulso da Cabeça , Neuronite Vestibular , Humanos , Estudos Prospectivos , Reflexo Vestíbulo-Ocular , Movimentos Sacádicos , Neuronite Vestibular/diagnóstico
7.
Acta Otolaryngol ; 140(4): 314-318, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31909683

RESUMO

Background: Intratympanic gentamicin injection (ITG) is a well-accepted means to treat intractable Meniere's disease (MD).Aims/Objectives: To investigate change of vestibule-ocular reflex (VOR) gain and pure-tone threshold after low-dose ITG for MD.Methods: Sixteen patients with definite MD who were treated by low-dose ITG were retrospectively reviewed. We defined VOR gain difference as an amount of decreased gain in video head impulse test one month after ITG. Patients were classified into two groups: single injection vs. multiple injections. Multiple injections group was composed of patients with poor vertigo control after initial ITG who required second or third ITG later in follow up period.Results: VOR gain differences of both horizontal and posterior canal plane were higher than those of anterior canal plane. Between two groups, mean VOR gain difference of horizontal canal plane in multiple injections group was lower than that in single injection group. Only two patients showed increased pure-tone threshold more than 10 dB.Conclusion and significance: Our results suggest that ITG appears to cause a differential loss of function across three semicircular canals. Furthermore, if VOR gain difference of horizontal canal is relatively low after initial ITG, patient might have poor vertigo control and be required another ITG.


Assuntos
Antibacterianos/uso terapêutico , Gentamicinas/uso terapêutico , Doença de Meniere/tratamento farmacológico , Reflexo Vestíbulo-Ocular/efeitos dos fármacos , Vertigem/tratamento farmacológico , Adulto , Idoso , Idoso de 80 Anos ou mais , Antibacterianos/farmacologia , Audiometria de Tons Puros , Limiar Auditivo , Gentamicinas/farmacologia , Teste do Impulso da Cabeça , Humanos , Injeção Intratimpânica , Pessoa de Meia-Idade , Estudos Retrospectivos , Canais Semicirculares/efeitos dos fármacos
9.
Nature ; 575(7783): 473-479, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31748722

RESUMO

Traditional technologies for virtual reality (VR) and augmented reality (AR) create human experiences through visual and auditory stimuli that replicate sensations associated with the physical world. The most widespread VR and AR systems use head-mounted displays, accelerometers and loudspeakers as the basis for three-dimensional, computer-generated environments that can exist in isolation or as overlays on actual scenery. In comparison to the eyes and the ears, the skin is a relatively underexplored sensory interface for VR and AR technology that could, nevertheless, greatly enhance experiences at a qualitative level, with direct relevance in areas such as communications, entertainment and medicine1,2. Here we present a wireless, battery-free platform of electronic systems and haptic (that is, touch-based) interfaces capable of softly laminating onto the curved surfaces of the skin to communicate information via spatio-temporally programmable patterns of localized mechanical vibrations. We describe the materials, device structures, power delivery strategies and communication schemes that serve as the foundations for such platforms. The resulting technology creates many opportunities for use where the skin provides an electronically programmable communication and sensory input channel to the body, as demonstrated through applications in social media and personal engagement, prosthetic control and feedback, and gaming and entertainment.


Assuntos
Realidade Aumentada , Desenho de Equipamento , Pele , Tato , Interface Usuário-Computador , Realidade Virtual , Tecnologia sem Fio/instrumentação , Comunicação , Epiderme , Retroalimentação , Feminino , Humanos , Masculino , Próteses e Implantes , Robótica , Mídias Sociais , Vibração , Jogos de Vídeo
10.
Otol Neurotol ; 40(6): 797-805, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30964776

RESUMO

OBJECTIVE: To analyze the clinical characteristics of acute vestibular neuritis (AVN) according to involvement site. STUDY DESIGN: Retrospective chart analysis. SETTING: Tertiary referral hospital. PATIENTS/INTERVENTIONS: Over a period of 3 years, we reviewed 133 cases of AVN. Patients were classified into three groups: 1) total vestibular neuritis (superior and inferior vestibular nerve involvement [TVN]); 2) superior vestibular neuritis (superior vestibular nerve involvement [SVN]); and 3) inferior vestibular neuritis (inferior vestibular nerve involvement [IVN]). MAIN OUTCOME MEASURE: We analyzed the clinical course and results of vestibular function tests (video-nystagmography, video head impulse test [vHIT], caloric test, and cervical vestibular evoked myogenic potential). RESULTS: In the study, there were 39.9% TVN cases, 48.1% SVN cases, and 12% IVN cases. The number of days to spontaneous nystagmus remission, hospital duration, and follow-up period were shorter in the IVN group than in the SVN and TVN groups. The symptom onset period was longer in the IVN group than in the SVN and TVN groups. Spontaneous nystagmus and head shaking nystagmus amplitude were smaller in the IVN group than in the SVN and TVN groups. Concordance of results between the caloric test, cervical vestibular evoked myogenic potential, and vHIT was relatively low in the IVN group. CONCLUSION: The IVN group had a shorter clinical course and weaker nystagmus in comparison with the TVN and SVN groups. The use of additional vHIT in the diagnosis of AVN can help provide a more accurate diagnosis of the rare subtype of IVN, which can be confused with various central lesions.


Assuntos
Potenciais Evocados Miogênicos Vestibulares/fisiologia , Nervo Vestibular/fisiopatologia , Neuronite Vestibular/diagnóstico , Vestíbulo do Labirinto/fisiopatologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Teste do Impulso da Cabeça/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Testes de Função Vestibular , Neuronite Vestibular/fisiopatologia , Adulto Jovem
11.
Science ; 363(6430)2019 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-30819934

RESUMO

Existing vital sign monitoring systems in the neonatal intensive care unit (NICU) require multiple wires connected to rigid sensors with strongly adherent interfaces to the skin. We introduce a pair of ultrathin, soft, skin-like electronic devices whose coordinated, wireless operation reproduces the functionality of these traditional technologies but bypasses their intrinsic limitations. The enabling advances in engineering science include designs that support wireless, battery-free operation; real-time, in-sensor data analytics; time-synchronized, continuous data streaming; soft mechanics and gentle adhesive interfaces to the skin; and compatibility with visual inspection and with medical imaging techniques used in the NICU. Preliminary studies on neonates admitted to operating NICUs demonstrate performance comparable to the most advanced clinical-standard monitoring systems.


Assuntos
Eletrônica/instrumentação , Terapia Intensiva Neonatal , Monitorização Fisiológica/instrumentação , Tecnologia sem Fio/instrumentação , Diagnóstico por Imagem , Desenho de Equipamento , Humanos , Recém-Nascido , Dispositivos Lab-On-A-Chip , Pele , Sinais Vitais
12.
Otolaryngol Head Neck Surg ; 160(5): 894-901, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30665325

RESUMO

OBJECTIVE: To analyze acute vertigo showing spontaneous nystagmus with negative video head impulse test (vHIT). STUDY DESIGN: Retrospective chart analysis. SETTING: Tertiary referral hospital. SUBJECTS AND METHODS: Over 16 months, 155 patients were identified with acute vertigo with spontaneous nystagmus. Of these 155, 30 (19.4%) were enrolled in this study because they did not show gain loss or catch-up saccades in both sides of the horizontal vHIT. Results of vestibular function tests (videonystagmography, horizontal vHIT, caloric test, and cervical vestibular-evoked myogenic potential [cVEMP]) and pure tone audiometry were analyzed. For all cases, magnetic resonance imaging with diffusion-weighted imaging was checked. RESULTS: Patients consisted of 17 with Ménière's disease and 7 with sudden sensorineural hearing loss with vertigo (SSNHL_V), and only 3 patients were finally diagnosed as having acute vascular stroke. Except for the loss of hearing on the lesion side, the direction of nystagmus or cVEMP asymmetry showed very different results. All 7 patients with SSNHL_V did not have canal paresis in the caloric test, but cVEMP amplitude was smaller on the lesion side for 6 patients. CONCLUSIONS: For patients with acute vertigo presenting spontaneous nystagmus with negative horizontal vHIT, it is important not only to focus on the diagnosis of acute vascular stroke but also to evaluate hearing because of the high possibility of Ménière's disease or SSNHL_V.


Assuntos
Perda Auditiva Neurossensorial/diagnóstico , Doença de Meniere/diagnóstico , Nistagmo Patológico/etiologia , Vertigem/etiologia , Neuronite Vestibular/diagnóstico , Adulto , Idoso , Audiometria de Tons Puros , Feminino , Teste do Impulso da Cabeça , Perda Auditiva Neurossensorial/complicações , Humanos , Masculino , Doença de Meniere/complicações , Pessoa de Meia-Idade , Estudos Retrospectivos , Potenciais Evocados Miogênicos Vestibulares , Testes de Função Vestibular , Neuronite Vestibular/complicações , Vestíbulo do Labirinto , Adulto Jovem
13.
ACS Nano ; 12(5): 4164-4171, 2018 05 22.
Artigo em Inglês | MEDLINE | ID: mdl-29641889

RESUMO

Recently developed approaches in deterministic assembly allow for controlled, geometric transformation of two-dimensional structures into complex, engineered three-dimensional layouts. Attractive features include applicability to wide ranging layout designs and dimensions along with the capacity to integrate planar thin film materials and device layouts. The work reported here establishes further capabilities for directly embedding high-performance electronic devices into the resultant 3D constructs based on silicon nanomembranes (Si NMs) as the active materials in custom devices or microscale components released from commercial wafer sources. Systematic experimental studies and theoretical analysis illustrate the key ideas through varied 3D architectures, from interconnected bridges and coils to extended chiral structures, each of which embed n-channel Si NM MOSFETs (nMOS), Si NM diodes, and p-channel silicon MOSFETs (pMOS). Examples in stretchable/deformable systems highlight additional features of these platforms. These strategies are immediately applicable to other wide-ranging classes of materials and device technologies that can be rendered in two-dimensional layouts, from systems for energy storage, to photovoltaics, optoelectronics, and others.


Assuntos
Eletrônica/instrumentação , Nanoestruturas/química , Silício/química , Análise de Elementos Finitos , Iluminação , Fenômenos Mecânicos , Metais/química , Óxidos/química , Dióxido de Silício
14.
Nat Commun ; 8: 15894, 2017 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-28635956

RESUMO

Low modulus, compliant systems of sensors, circuits and radios designed to intimately interface with the soft tissues of the human body are of growing interest, due to their emerging applications in continuous, clinical-quality health monitors and advanced, bioelectronic therapeutics. Although recent research establishes various materials and mechanics concepts for such technologies, all existing approaches involve simple, two-dimensional (2D) layouts in the constituent micro-components and interconnects. Here we introduce concepts in three-dimensional (3D) architectures that bypass important engineering constraints and performance limitations set by traditional, 2D designs. Specifically, open-mesh, 3D interconnect networks of helical microcoils formed by deterministic compressive buckling establish the basis for systems that can offer exceptional low modulus, elastic mechanics, in compact geometries, with active components and sophisticated levels of functionality. Coupled mechanical and electrical design approaches enable layout optimization, assembly processes and encapsulation schemes to yield 3D configurations that satisfy requirements in demanding, complex systems, such as wireless, skin-compatible electronic sensors.

15.
Science ; 355(6325): 616-619, 2017 02 10.
Artigo em Inglês | MEDLINE | ID: mdl-28183975

RESUMO

Dual-functioning displays, which can simultaneously transmit and receive information and energy through visible light, would enable enhanced user interfaces and device-to-device interactivity. We demonstrate that double heterojunctions designed into colloidal semiconductor nanorods allow both efficient photocurrent generation through a photovoltaic response and electroluminescence within a single device. These dual-functioning, all-solution-processed double-heterojunction nanorod light-responsive light-emitting diodes open feasible routes to a variety of advanced applications, from touchless interactive screens to energy harvesting and scavenging displays and massively parallel display-to-display data communication.

16.
ACS Nano ; 10(5): 4920-5, 2016 05 24.
Artigo em Inglês | MEDLINE | ID: mdl-27078621

RESUMO

Here, we report multilayer stacking of films of quantum dots (QDs) for the purpose of tailoring the energy band alignment between charge transport layers and light emitting layers of different color in quantum dot light-emitting diodes (QD LED) for maximum efficiency in full color operation. The performance of QD LEDs formed by transfer printing compares favorably to that of conventional devices fabricated by spin-casting. Results indicate that zinc oxide (ZnO) and titanium dioxide (TiO2) can serve effectively as electron transport layers (ETLs) for red and green/blue QD LEDs, respectively. Optimized selections for each QD layer can be assembled at high yields by transfer printing with sacrificial fluoropolymer thin films to provide low energy surfaces for release, thereby allowing shared common layers for hole injection (HIL) and hole transport (HTL), along with customized ETLs. This strategy allows cointegration of devices with heterogeneous energy band diagrams, in a parallelized scheme that offers potential for high throughput and practical use.

17.
Nano Lett ; 15(2): 969-73, 2015 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-25584701

RESUMO

Here we demonstrate materials and operating conditions that allow for high-resolution printing of layers of quantum dots (QDs) with precise control over thickness and submicron lateral resolution and capabilities for use as active layers of QD light-emitting diodes (LEDs). The shapes and thicknesses of the QD patterns exhibit systematic dependence on the dimensions of the printing nozzle and the ink composition in ways that allow nearly arbitrary, systematic control when exploited in a fully automated printing tool. Homogeneous arrays of patterns of QDs serve as the basis for corresponding arrays of QD LEDs that exhibit excellent performance. Sequential printing of different types of QDs in a multilayer stack or in an interdigitated geometry provides strategies for continuous tuning of the effective, overall emission wavelengths of the resulting QD LEDs. This strategy is useful to efficient, additive use of QDs for wide ranging types of electronic and optoelectronic devices.

19.
J Phys Chem B ; 110(37): 18455-8, 2006 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-16970471

RESUMO

Using first-principles density-functional calculations, we investigated two competing pathways for the dissociation of water and ammonia on a Si(001) surface. For both systems, we found that, in addition to the conventionally accepted intradimer transfer of the H atom, the interdimer transfer of the H atom can be equally probable with the same reaction mechanism. Our analysis shows that the two dissociation pathways occur through the Lewis acid-base reaction between the partially positive H ion and the electron-abundant up atom of the buckled Si dimer. The result of the interdimer H transfer not only supports a recently proposed model for C-defect on Si(001) but also corresponds to the recent scanning tunneling microscopy data of ammonia dissociation on Si(001).

20.
J Chem Phys ; 121(16): 8010-3, 2004 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-15485264

RESUMO

Using first-principles density-functional calculations we predict a self-directed growth of benzonitrile molecular line on a H-terminated Si(001) surface. The C[triple bond]N bond of benzonitrile reacts with a single Si dangling bond which can be generated by the removal of a H atom, forming one Si-N bond and one C radical. Subsequently, the produced C radical can be stabilized by abstracting a H atom from a neighboring Si dimer, creating another H-empty site. This H-abstraction process whose activation barrier is 0.65 eV sets off a chain reaction to grow one-dimensional benzonitrile line along the Si dimer row. Our calculated energy profile for formation of the benzonitrile line shows its relatively easier formation compared with previously reported styrene and vinylferrocene lines.

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