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1.
Inorg Chem ; 63(19): 8889-8898, 2024 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-38693871

RESUMEN

Phosphor-in-glass represents a promising avenue for merging the luminous efficiency of high-quality phosphor and the thermal stability of a glass matrix. Undoubtedly, the glass matrix system and its preparation are pivotal factors in achieving high stability and preserving the original performance of embedded phosphor particles. In contrast to the well-established commercial Y3Al5O12:Ce3+ oxide phosphor, red nitride phosphor, which plays a critical role in high-quality lighting, exhibits greater structural instability during the high-temperature synthesis of inorganic glasses. A telluride glass with a refractive index (RI = 2.15@615 nm) akin to that of nitride phosphor (∼2.19) has been devised, demonstrating high efficiency in photon utilization. The lower glass-transition temperature plays a crucial role in safeguarding phosphor particles against erosion resulting from exposure to high-temperature melts. Phosphor-in-glass retains 93% of the quantum efficiency observed for pure phosphor. The assembled white light-emitting diodes module has precise color tuning capabilities, achieving an optimal color rendering index of 93.7, a luminous efficacy of 80.4 lm/W, and a correlated color temperature of 5850 K. These outcomes hold potential for advancing the realm of inorganic package and high-quality white light illumination.

2.
Luminescence ; 39(1): e4555, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37461122

RESUMEN

A green phosphor Sr2 ZnGe2 O7 :Mn2+ with a melilite structure was prepared using a high-temperature solid-state reaction. When the 535 nm emission was monitored, the excitation spectrum of the Sr2 ZnGe2 O7 :Mn2+ was found to contain two excitation bands in the ultraviolet (UV) region. When excited by UV light, the sample shows bright green emission at 535 nm, which corresponds to the distinctive transition of Mn2+ (4 T1 →6 A1 ). Moreover, the quantum efficiency of Sr2 ZnGe2 O7 :Mn2+ could reach 67.6%. Finally, a high-performance white-light-emitting diode (WLED) with a low correlated colour temperature of 4632 K and a high colour rendering index (CRI) of 92.3 were packaged by coating commercial blue and red phosphors with an optimized Sr2 ZnGe2 O7 :Mn2+ sample on a 310 nm UV chip. This indicated that Sr2 ZnGe2 O7 :Mn2+ has the potential application as a green component in the WLED lighting field.


Asunto(s)
Sustancias Luminiscentes , Sustancias Luminiscentes/química , Luz Verde , Luminiscencia , Rayos Ultravioleta
3.
J Am Chem Soc ; 143(14): 5470-5480, 2021 Apr 14.
Artículo en Inglés | MEDLINE | ID: mdl-33794093

RESUMEN

The synthesis of highly luminescent colloidal CsSnX3 (X = halogen) perovskite nanocrystals (NCs) remains a long-standing challenge due to the lack of a fundamental understanding of how to rationally suppress the formation of structural defects that significantly influence the radiative carrier recombination processes. Here, we develop a theory-guided, general synthetic concept for highly luminescent CsSnX3 NCs. Guided by density functional theory calculations and molecular dynamics simulations, we predict that, although there is an opposing trend in the chemical potential-dependent formation energies of various defects, highly luminescent CsSnI3 NCs with narrow emission could be obtained through decreasing the density of tin vacancies. We then develop a colloidal synthesis strategy that allows for rational fine-tuning of the reactant ratio in a wide range but still leads to the formation of CsSnI3 NCs. By judiciously adopting a tin-rich reaction condition, we obtain narrow-band-emissive CsSnI3 NCs with a record emission quantum yield of 18.4%, which is over 50 times larger than those previously reported. Systematic surface-state characterizations reveal that these NCs possess a Cs/I-lean surface and are capped with a low density of organic ligands, making them an excellent candidate for optoelectronic devices without any postsynthesis ligand management. We showcase the generalizability of our concept by further demonstrating the synthesis of highly luminescent CsSnI2.5Br0.5 and CsSnI2.25Br0.75 NCs. Our findings not only highlight the value of computation in guiding the synthesis of high-quality colloidal perovskite NCs but also could stimulate intense efforts on tin-based perovskite NCs and accelerate their potential applications in a range of high-performance optoelectronic devices.

4.
Small ; 16(40): e2004126, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32876996

RESUMEN

Recently, all-inorganic halide perovskite (CsPbX3 , (X = Cl, Br, and I)) nanocrystals (NCs) based hybrid architectures have attracted extensive attention owing to their distinct luminescence characteristics. However, due to stress and lattice mismatch, it is still a challenge to construct heterojunctions between perovskite NCs and the nanostructures with different lattice parameters and non-cubic contour. In this work, a room temperature mechanochemical method is presented to construct TiO2 @CsPbBr3 hybrid architectures, in which TiO2 nanoparticles (NPs) with a hard lattice as nano "balls" mill off the angles and anchor to the CsPbBr3 NCs with a soft lattice. On the contrary, to ball-mill without TiO2 or with conventional ceramics balls replacing TiO2 , CsPbBr3 NCs still maintain cubic contour deriving from their cubic crystal structures. Moreover, the TiO2 @CsPbBr3 architectures display distinct improvement of photoluminescence quantum yields and more excellent thermal stability in contrast with pristine CsPbBr3 owing to the passivation of surface defect, small surface area, and energy transfer from CsPbBr3 to TiO2 . Meanwhile, there is distinct luminous decay characteristic under the radiation of UV and visible light due to the "on" and "off" TiO2 response. The method provides an alternative strategy to acquire other anchoring heterojunctions based on perovskite NCs for further regulating their luminescent characteristics.

5.
J Am Chem Soc ; 141(38): 15423-15432, 2019 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-31469556

RESUMEN

The presence of labile bulky insulating hydrocarbon ligands in halide perovskite nanocrystals (NCs) passivates surface traps but concurrently makes charge transport difficult in optoelectronic devices. Early efforts routinely rely on the replacement of long-chain ligands with short-chain cousins, leading to notable changes in NC's sizes and photophysical properties and thus making it hard to obtain devices with nearly designed emissions. Here we report a general solution-phase ligand-exchange strategy to produce organic-ligand-lacking halide perovskite NCs with high photoluminescence (PL) quantum yields and good stability in ambient air. We demonstrate that the ligand exchange can be achieved by a well-controlled mild reaction of thionyl halide with the carboxylic and amine groups on the NC's surface, resulting in nearly dry NCs with well-passivated surfaces and almost unaltered emission characteristics. Consequently, we achieve exceptionally high-performance blue perovskite NC light-emitting diodes (LEDs) with an external quantum efficiency of up to 1.35% and an extremely narrow full width at half-maximum of 14.6 nm. Our work provides a systematic framework for preparing high-quality organic-ligand-lacking perovskite NC inks that can be directly cast as films featuring effective charge transport, thereby providing the foundation for further development of a wide range of efficient perovskite optoelectronic devices.

6.
Angew Chem Int Ed Engl ; 55(16): 4967-71, 2016 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-26971863

RESUMEN

A low-temperature topochemical reduction strategy is used herein to prepare unconventional phosphors with luminescence covering the biological and/or telecommunications optical windows. This approach is demonstrated by using Bi(III)-doped Y2O3 (Y(2-x)Bi(x)O3) as a model system. Experimental results suggest that topochemical treatment of Y(2-x)Bi(x)O3 using CaH2 creates randomly distributed oxygen vacancies in the matrix, resulting in the change of the oxidation states of Bi to lower oxidation states. The change of the Bi coordination environments from the [BiO6] octahedra in Y(2-x)Bi(x)O3 to the oxygen-deficient [BiO(6-z)] polyhedra in reduced phases leads to a shift of the emission maximum from the visible to the near-infrared region. The generality of this approach was further demonstrated with other phosphors. Our findings suggest that this strategy can be used to explore Bi-doped or other classes of luminescent systems, thus opening up new avenues to develop novel optical materials.

7.
Dalton Trans ; 53(9): 4175-4184, 2024 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-38319141

RESUMEN

Cyan phosphors are urgently needed to fill the cyan gap and improve the spectral continuity of white light-emitting diodes (LEDs) to cater to the high demand for high-quality lighting. Here, a series of new Eu2+-activated La3Si6.5Al1.5N9.5O5.5 (LSANO) cyan phosphors were prepared, and their luminescence properties and color centers were analyzed through fluorescence spectral measurements from 7 K to 475 K. At 300 K, the photoluminescence excitation (PLE) spectrum monitored at 483 nm presents a broadband of 200-460 nm with a peak at 398 nm, matching well with commercial violet LED chips. When excited by 398 nm violet light, the photoluminescence emission (PL) spectrum of LSANO:0.01Eu2+ exhibits a cyan emission band at about 483 nm. At 7 K, the emission spectrum clearly shows an asymmetric emission band and the emission peak wavelength changes from 483 nm (300 K) to 500 nm (7 K), indicating that there are two possible color centers in the LSANO:Eu2+ phosphor. Moreover, the maximum emission value can be adjusted from 480 to 499 nm by adjusting the doping content of Eu2+. Finally, a violet-chip-based white LED with the optimized color quality of Ra = 91.4, Rf = 90.1, and Rg = 93.6 was fabricated by adding the prepared cyan phosphor, verifying the potential application of the prepared cyan phosphor LSANO:Eu2+ in high-quality white LEDs.

8.
ACS Appl Mater Interfaces ; 16(23): 30176-30184, 2024 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-38826007

RESUMEN

Single-component white-light luminescent materials are considered an economical and facile choice for phosphor-converted white light-emitting diodes (pc-WLEDs). Here, a new single-component white-light-emitting material Cs2MnCl4:Eu2+ based on the combination of a lead-free halide structure and a rare-earth ion is first reported. Benefiting from the smart dilution-sensitization design strategy, white light composed of dual broad emission originating from Eu2+ (blue light, 444 nm, 4f65d1 → 4f7) and Mn2+ (yellow light, 566 nm, 4T1g → 6A1g) was successfully realized under near-ultraviolet light (404 nm) radiation with a high photoluminescence quantum yield of 66%. Based on the single-source Cs2MnCl4:Eu2+ phosphor, a pc-WLEDs device with "eye-friendly" white light production was successfully fabricated. The pc-WLEDs exhibit suitable color coordinates of (0.3294, 0.2746) and a high color rendering index of 82.3, demonstrating the potential in the future health-conscious illumination application by reducing the risk of eye strain and high-energy blue-light damage. This work achieves a new single-component white-light-emitting Mn-based halide phosphor and provides a new path for the design of single-component white light sources in Mn-based halides.

9.
Materials (Basel) ; 17(8)2024 Apr 18.
Artículo en Inglés | MEDLINE | ID: mdl-38673221

RESUMEN

Heterojunction semiconductors have been extensively applied in various optoelectronic devices due to their unique carrier transport characteristics. However, it is still a challenge to construct heterojunctions based on colloidal quantum dots (CQDs) due to stress and lattice mismatch. Herein, HgSe/CsPbBrxI3-x heterojunctions with type I band alignment are acquired that are derived from minor lattice mismatch (~1.5%) via tuning the ratio of Br and I in halide perovskite. Meanwhile, HgSe CQDs with oleylamine ligands can been exchanged with a halide perovskite precursor, acquiring a smooth and compact quantum dot film. The photoconductive detector based on HgSe/CsPbBrxI3-x heterojunction presents a distinct photoelectric response under an incident light of 630 nm. The work provides a promising strategy to construct CQD-based heterojunctions, simultaneously achieving inorganic ligand exchange, which paves the way to obtain high-performance photodetectors based on CQD heterojunction films.

10.
Dalton Trans ; 52(36): 12862-12868, 2023 Sep 19.
Artículo en Inglés | MEDLINE | ID: mdl-37622468

RESUMEN

Atomically thin two-dimensional (2D) bismuth oxychalcogenides have been considered as promising candidates for high-speed and low-power photoelectronic devices due to their high charge carrier mobility and excellent environmental stability. However, the photoelectric performance of their bulk materials still falls short of expectations. Herein, a novel Bi9O7.5S6/SnS composite film with a type-II heterojunction was successfully prepared by combining hydrothermal and knife-coating techniques. The crystal structure, morphology, and optical properties were systematically investigated. Under 1 V bias voltage, the photocurrent of the Bi9O7.5S6/SnS composite film can be obtained as 107 µA cm-2, which is about 29.9 times and 93.9 times higher than that of bare Bi9O7.5S6 and SnS, respectively. The type-II heterojunction has played a significant role in improving the photoelectric performance of the Bi9O7.5S6/SnS composite film by facilitating the separation and transfer of photo-generated carriers. This work sheds light on the design and development of new bismuth-based composite materials for advanced photoelectric and photocatalytic applications.

11.
J Tradit Chin Med ; 32(4): 534-7, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23427384

RESUMEN

OBJECTIVE: To observe the therapeutic effect of lumbar tender point deep tissue massage plus lumbar traction on chronic non-specific low back pain using change in pressure pain threshold, muscle hardness and pain intensity as indices. METHODS: We randomly divided 64 patients into a treatment group (32 cases) and a control group (32 cases). Two drop-outs occurred in each group. Patients in the treatment group received tender point deep tissue massage plus lumbar traction and patients in the control group received lumbar traction, alone. We used a tissue hardness meter/algometer and visual analog scale (VAS) to assess the pressure pain threshold, muscle hardness and pain intensity. RESULTS: Following treatment, we obtained the following results in the treatment and control groups, respectively: the pressure pain threshold difference was 1.5 +/- 0.8 and 1.1 +/- 0.7; the muscle hardness difference was 4.2 +/- 1.6 and 3.5 +/- 1.3; and the VAS score difference was 1.9 +/- 0.9 and 1.4 +/- 0.8. Compared to the control group, the treatment group had higher pressure pain threshold (t = 2.09, P < 0.05), and lower muscle hardness (t = 2.05, P < 0.05) and pain intensity (t = 2.46, P < 0.05). CONCLUSION: Lumbar tender point deep tissue massage combined with lumbar traction produced better improvement in pressure pain threshold, muscle hardness and pain intensity in patients with chronic non-specific low back pain than with lumbar traction alone.


Asunto(s)
Dolor de la Región Lumbar/terapia , Masaje , Puntos de Acupuntura , Adulto , Anciano , Femenino , Humanos , Región Lumbosacra , Masculino , Persona de Mediana Edad , Resultado del Tratamiento , Adulto Joven
12.
Zhong Xi Yi Jie He Xue Bao ; 10(1): 54-8, 2012 Jan.
Artículo en Zh | MEDLINE | ID: mdl-22237275

RESUMEN

BACKGROUND: Cervical spondylotic radiculopathy is a commonly encountered and frequently occurring disease. Traditional Chinese osteopathic manipulations may have better therapeutic efficacy than that of other methods in treating patients with cervical spondylotic radiculopathy. OBJECTIVE: To evaluate the clinical therapeutic effects of cervical fixed-point traction manipulation in treating patients with cervical spondylotic radiculopathy. DESIGN, SETTING, PARTICIPANTS AND INTERVENTIONS: A prospective, randomized controlled trial was adopted. Eighty-four patients with cervical spondylotic radiculopathy were randomly divided into treatment group (n=42) and control group (n=42). All patients were enrolled from the outpatient service of Department of Rehabilitation of Chinese PLA General Hospital of China. Patients received oral and written information about clinical procedures before giving their written informed consent. The patients were treated with cervical fixed-point traction manipulation (treatment group) or cervical computer traction (control group). Cervical fixed-point traction was performed once every other day for a total of seven treatment periods and cervical computer traction was performed 30 min, once per day for 14 d. MAIN OUTCOME MEASURES: Before and after treatment, visual analogue scale (VAS) score and temperature of upper limb skin (normal limb and abnormal limb) detected by infrared thermal imaging system were contrastively analyzed. RESULTS: Five patients were lost to follow-up, one patient in the treatment group and four patients in the control group. There were significant differences in VAS score and temperature difference between the normal and abnormal upper limbs of infrared thermal imaging in the treatment group (t=28.652, P<0.01; t=64.214, P<0.01) or in the control group (t=14.484, P<0.05; t=84.425, P<0.05) compared between before and after treatment. After treatment, the changes in VAS score and temperature difference of normal and abnormal upper limbs in the treatment group were more obvious compared with the control group (t=7.494, P<0.01; t=5.321, P<0.01). CONCLUSION: Cervical fixed-point traction manipulation has better efficacy than cervical computer traction in treating patients with cervical spondylotic radiculopathy.


Asunto(s)
Manipulación Espinal/métodos , Radiculopatía/terapia , Espondilosis/terapia , Adulto , Anciano , Vértebras Cervicales , Humanos , Persona de Mediana Edad , Estudios Prospectivos , Resultado del Tratamiento
13.
Dalton Trans ; 51(44): 17022-17029, 2022 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-36301175

RESUMEN

Layered bismuth oxychalcogenides have been demonstrated as potential candidates for high-speed and low-power electronics due to their outstanding environmental stability and high carrier mobility, but the photoelectric performance of bulk species is still far from satisfactory. Herein, a novel Bi9O7.5S6/CdS composite film with a type-II heterojunction has been successfully prepared by combining chemical bath deposition (CBD) and spin-coating technologies. The structure, morphology, optical and photoelectric properties of the samples were investigated systematically. The photoelectric current of the Bi9O7.5S6/CdS composite film was obtained as 32.49 µA cm-2 at 1 V, which is about 13.9-fold and 3.3-fold higher than those of bare Bi9O7.5S6 and CdS. An enhanced photoelectric response and photostability were achieved in the Bi9O7.5S6/CdS composite film, and can be appropriately attributed to the improved separation and transfer of photogenerated carriers driven by the type-II heterojunction. This work offers a promising route to develop high-performance visible-light photoelectric devices with type-II heterojunctions.

14.
Zhong Xi Yi Jie He Xue Bao ; 9(2): 153-7, 2011 Feb.
Artículo en Zh | MEDLINE | ID: mdl-21288450

RESUMEN

BACKGROUND: Pain due to chronic soft tissue injury of the neck and shoulder is a commonly encountered and frequently occurring condition. Traditional Chinese medicine is a common course of treatment for soft tissue injury and may have better therapeutic effects than biomedical options. OBJECTIVE: To evaluate the clinical therapeutic effects of Chinese herbal medicine warming meridians to nourish blood on chronic pain due to soft tissue injury in the neck and shoulder. DESIGN, SETTING, PARTICIPANTS AND INTERVENTIONS: A random and control method was adopted. Sixty-three patients with pain of the neck and shoulder due to chronic soft tissue injury, presenting with blood deficiency and cold coagulation syndrome, were randomly divided into treatment group (n=32) and control group (n=31). There was a drop-out case in treatment group. All the patients were collected from the clinic service of the Department of Rehabilitation at the General Hospital of the People's Liberation Army. Patients received oral and written information about clinical procedures before signing their written informed consent. Patients in the treatment group were treated with Chinese herbal decoctions for warming meridians to nourish blood and cervical traction. Patients in the control group were treated with cervical traction. The course of treatment was 14 days. MAIN OUTCOME MEASURES: A visual analog scale (VAS) was used to record test data in the two groups before and after treatment, and therapeutic effect was compared after treatment between the two groups. RESULTS: After treatment, VAS scores of the treatment group and the control group were decreased as compared with before treatment (t=5.01, P<0.01; t=4.91, P<0.01). Difference of VAS scores between before and after treatment in the treatment group was higher than that in the control group (t=2.44, P0.05). CONCLUSION: The treatment method of warming meridians to nourish blood combined with cervical traction has better therapeutic effect than only applying traction for chronic pain due to soft tissue injury of the neck and shoulder.


Asunto(s)
Dolor Crónico/terapia , Medicina Tradicional China , Dolor de Cuello/terapia , Traumatismos de los Tejidos Blandos/terapia , Adulto , Anciano , Enfermedad Crónica , Femenino , Humanos , Masculino , Persona de Mediana Edad , Fitoterapia , Estudios Prospectivos , Hombro , Adulto Joven
15.
Materials (Basel) ; 14(18)2021 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-34576541

RESUMEN

In this work, a novel red-emitting oxyfluoride phosphor Na2NbOF5:Mn4+ with an ultra-intense zero-phonon line (ZPL) was successfully synthesized by hydrothermal method. The phase composition and luminescent properties of Na2NbOF5:Mn4+ were studied in detail. The photoluminescence excitation spectrum contains two intense excitation bands centered at 369 and 470 nm, which match well with commercial UV and blue light-emitting diode (LED) chips. When excited by 470 nm blue light, Na2NbOF5:Mn4+ exhibits red light emission dominated by ZPL. Notably, the color purity of the Na2NbOF5:Mn4+ red phosphor can reach 99.9%. Meanwhile, the Na2NbOF5:Mn4+ phosphor has a shorter fluorescence decay time than commercial K2SiF6:Mn4+, which is conducive to fast switching of images in display applications. Profiting from the intense ZPL, white light-emitting diode (WLED) with high color rendering index of Ra = 86.2 and low correlated color temperature of Tc = 3133 K is realized using yellow YAG:Ce3+ and red Na2NbOF5:Mn4+ phosphor. The WLED fabricated using CsPbBr3 quantum dots (QDs) and red Na2NbOF5:Mn4+ phosphor shows a wide color gamut of 127.56% NTSC (National Television Standard Committee). The results show that red-emitting Na2NbOF5:Mn4+ phosphor has potential application prospects in WLED lighting and display backlight.

16.
Chem Commun (Camb) ; 57(98): 13393-13396, 2021 Dec 09.
Artículo en Inglés | MEDLINE | ID: mdl-34825674

RESUMEN

A novel quaternary oxysulfide, FeOCuS has been successfully synthesized with a tetragonal anti-PbO-type structure and a visible-light bandgap of about 1.37 eV. Driven by only a 0.4 V bias voltage under simulated AM 1.5 G illumination, a high photocurrent density of 3.89 mA cm-2 has been achieved, revealing the potential optoelectronic applications.

17.
Nanomaterials (Basel) ; 11(1)2020 Dec 25.
Artículo en Inglés | MEDLINE | ID: mdl-33375563

RESUMEN

Pulsed laser deposition on 3-dimensional micro-objects of complex morphology is demonstrated by the paradigmatic growth of cellulose and polymer/Y3Al5O12:Ce phosphor composite nanolayers. Congruent materials transfer is a result of multicomponent ablation performed by relatively low fluence (<200 mJ cm-2) ArF excimer laser pulses (λ = 193 nm). Films grown on optical and engineering components, having a thickness from ~50 nm to more than ~300 nm, are durable, well adherent and maintain the structural and functional properties of the parent solids. The results verify the unique capabilities of deep-ultraviolet pulsed laser deposition of novel functional nanostructures on arbitrary surface morphologies and highlight its potential in future 3-dimensional nanotechnologies.

18.
Nanoscale ; 11(35): 16499-16507, 2019 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-31453602

RESUMEN

Recently, CsPbX3 (X = Cl, Br, and I) perovskite quantum dots (QDs) have exhibited significant potential for application in the field of lighting. However, their self-absorption and agglomeration significantly decrease their photoluminescence when their solution is centrifuged to form a powder; this hinders their applications in the field of solid-state lighting. Currently, there is lack of efficient solutions to overcome the self-absorption issue for CsPbX3 QDs. Thus, herein, an effective strategy is proposed via the in situ growth of CsPbBr3 (CPB) QDs in a mesoporous silica (m-SiO2) matrix, where self-absorption originating from the agglomeration of the QD powder is distinctly suppressed in the m-SiO2 matrix. Furthermore, due to its higher transmissivity, some photons can transport along the channels of m-SiO2 with less light loss. As a result, the photoluminescence quantum yield (PLQY) of 68% for the CsPbBr3/m-SiO2 (CPB/MS) powder is distinctly higher than that of the discrete CPB powder (36%). In addition, the chemical stability, thermal quenching and luminous decay were evidently improved for the CPB/MS nanocomposite. Finally, a remote flexible light-emitting diode with ultrahigh stability and arbitrary bending angle was achieved, which presented a pathway for the application of CPB QDs in solid-state lighting.

19.
Am J Phys Med Rehabil ; 95(7): 483-94, 2016 07.
Artículo en Inglés | MEDLINE | ID: mdl-27333534

RESUMEN

OBJECTIVE: To investigate the impact of diameter of needles on the effect of dry needling treatment of chronic lumbar myofascial pain syndrome. DESIGN: Forty-eight patients with chronic lumbar myofascial pain syndrome were randomly allocated to 3 groups. They received dry needling with needles of diameter 0.25 (group A), 0.5 (group B), and 0.9 mm (group C). Visual analog scale evaluation and health survey were conducted at baseline and 3 months after the treatment. RESULTS: Visual analog scale scores were significantly different in all groups from baseline to 3 months. Visual analog scale scores at 3 months showed differences between group C and the other 2 groups. When baseline and 3 months after treatment (0 day and 3 months) in each of the 3 groups was compared, there was a difference between group C and group B. The Short Form (36) Health Survey scores from baseline to 3 months were different within the treatment groups. CONCLUSIONS: Visual analog scale score evaluations at 3 months showed efficacy in all groups. Results of 3 months showed that efficacy of treatment with larger needles (0.9-mm diameter) was better than that of smaller ones (0.5-mm diameter). The Short Form (36) Health Survey scores at 3 months indicated that treatments with needles of varying diameters were all effective, and when the results of 3 months were compared, there was no difference between the 3 groups.


Asunto(s)
Terapia por Acupuntura/instrumentación , Síndromes del Dolor Miofascial/terapia , Agujas , Terapia por Acupuntura/métodos , Adulto , Enfermedad Crónica , Femenino , Humanos , Cuidados a Largo Plazo/métodos , Región Lumbosacra , Masculino , Persona de Mediana Edad , Dimensión del Dolor , Factores de Tiempo , Resultado del Tratamiento
20.
J Phys Chem Lett ; 7(14): 2735-41, 2016 Jul 21.
Artículo en Inglés | MEDLINE | ID: mdl-27377481

RESUMEN

Doping of semiconductors by introducing foreign atoms enables their widespread applications in microelectronics and optoelectronics. We show that this strategy can be applied to direct bandgap lead-halide perovskites, leading to the realization of ultrawide photoluminescence (PL) at new wavelengths enabled by doping bismuth (Bi) into lead-halide perovskites. Structural and photophysical characterization reveals that the PL stems from one class of Bi doping-induced optically active center, which is attributed to distorted [PbI6] units coupled with spatially localized bipolarons. Additionally, we find that compositional engineering of these semiconductors can be employed as an additional way to rationally tune the PL properties of doped perovskites. Finally, we accomplished the electroluminescence at cryogenic temperatures by using this system as an emissive layer, marking the first electrically driven devices using Bi-doped photonic materials. Our results suggest that low-cost, earth-abundant, solution-processable Bi-doped perovskite semiconductors could be promising candidate materials for developing optical sources operating at new wavelengths.

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