ABSTRACT
Artificial sensory afferent nerves that emulate receptor nanochannel perception and synaptic ionic information processing in chemical environments are highly desirable for bioelectronics. However, challenges persist in achieving life-like nanoscale conformal contact, agile multimodal sensing response, and synaptic feedback with ions. Here, a precisely tuned phase transition poly(N-isopropylacrylamide) (PNIPAM) hydrogel is introduced through the water molecule reservoir strategy. The resulting hydrogel with strongly cross-linked networks exhibits excellent mechanical performance (â¼2000% elongation) and robust adhesive strength. Importantly, the hydrogel's enhanced ionic conductance and heterogeneous structure of the temperature-sensitive component enable highly sensitive strain information perception (GFmax = 7.94, response time â¼ 87 ms), temperature information perception (TCRmax = -1.974%/°C, response time â¼ 270 ms), and low energy consumption synaptic plasticity (42.2 fJ/spike). As a demonstration, a neuromorphic sensing-synaptic system is constructed integrating iontronic strain/temperature sensors with fiber synapses for real-time information sensing, discrimination, and feedback. This work holds enormous potential in bioinspired robotics and bioelectronics.
Subject(s)
Acrylic Resins , Hydrogels , Hydrogels/chemistry , Acrylic Resins/chemistry , Temperature , Synapses/physiology , Adhesives/chemistryABSTRACT
Cesium lead halide perovskite nanocrystals (CLHP NCs) have drawn considerable attention because of their promising optoelectrical properties. However, owing to the extreme vulnerability of CLHP NCs to water and polar alcohols, until now most synthesis approaches inevitably adopted ecounfriendly solvents. It is still a challenge to employ green polar alcohol (ethanol) as a solvent to synthesize CLHP NCs. In this work, we realized the room-temperature in situ synthesis of CsPbBr3/SiO2 sol entirely in ethanol by innovatively constructing amine-functionalized silica micelles, which originated from the synergistic effect of 3-aminopropyltriethoxysilane and tetraethylorthosilicate (TEOS) during an acid-catalyzed sol-gel process. The sol exhibited high stability and an absolute photoluminescence quantum yield of 61.9% in ethanol without a further modification process. The light-emitting intensity of the sol preserved for 34 days merely declined to 62.1%. This work sheds light on the less common strategy of directly synthesizing CsPbBr3 NCs and long-term stable preservation in a strongly polar solvent.
ABSTRACT
Cesium lead halide perovskite nanocrystals (CLHP NCs) have drawn considerable attention because of their promising optoelectrical properties. However, owing to extreme vulnerability of CLHP NCs to water and polar alcohols, up to date, most of the synthesis approaches have inevitably adopted eco-unfriendly solvents. It is still a big challenge to employ green polar alcohol (ethanol) as a solvent to synthesize CLHP NCs. In this work, we realized a room-temperature in situ synthesis of CsPbBr3/SiO2 sol entirely in ethanol by innovatively constructing amine-functionalized silica micelles, which is originated from the synergistic effect of 3-aminopropyltriethoxysilane and tetraethyl orthosilicate (TEOS) during an acid-catalyzed sol-gel process. The sol exhibited high stability and an absolute photoluminescence quantum yield of 61.9% in ethanol without a further modification process. The light emitting intensity of the sol preserved for 34 days merely declined to 62.1%. This work sheds light on the less common strategy of directly synthesizing CsPbBr3 NCs and long-term stable preservation in a strong polar solvent.
ABSTRACT
In recent years, all-inorganic lead-halide perovskites have received extensive attention due to their many advantages, but their poor stability and high toxicity are two major problems. In this paper, a low toxicity and stable Cs2SnCl6 double perovskite crystals were prepared by aqueous phase precipitation method using SnCl2 as precursor. By the XRD, ICP-AES, XPS, photoluminescence and absorption spectra, the fluorescence decay curve, the structure and photoluminescence characteristics of Ce3+-doped and undoped samples have been investigated in detail. The results show that the photoluminescence originates from defects. [ S n S n 4 + 2 + +VCl] defect complex in the crystal is formed by Sn2+ substituting Sn4+. The number of defects formed by Sn2+ in the crystal decreases with Ce3+ content increases. Within a certain number of defects, the crystal luminescence is enhanced with the number of [ S n S n 4 + 2 + +VCl] decreased. When Ce3+ is incorporated into the crystals, the defects of [ C e 3 + S n 4 + +VCl] and [ S n S n 4 + 2 + +VCl] were formed and the crystal show the strongest emission. This provides a route to enhance the photoluminescence of Cs2SnCl6 double perovskite crystals.
ABSTRACT
We report on the bluish green upconversion luminescence of niobium ions doped silicate glass by a femtosecond laser irradiation. The dependence of the fluorescence intensity on the pump power density of laser indicates that the conversion of infrared irradiation to visible emission is dominated by three-photon excitation process. We suggest that the charge transfer from O(2-) to Nb(5+) can efficiently contribute to the bluish green emission. The results indicate that transition metal ions without d electrons play an important role in fields of optics when embedded into silicate glass matrix.
Subject(s)
Glass/chemistry , Glass/radiation effects , Lasers , Luminescence , Niobium/chemistry , Photons , Silicates/chemistry , Spectrum Analysis , Time FactorsSubject(s)
Acute Lung Injury , NF-kappa B , Acute Lung Injury/genetics , Acute Lung Injury/metabolism , Animals , Humans , Lung/metabolism , Mice , Mice, Inbred C57BL , NF-kappa B/metabolismSubject(s)
Bacterial Infections , Diabetes Mellitus, Type 2 , Aged , Bacteria , Diabetes Mellitus, Type 2/complications , HumansABSTRACT
A new red phosphor, Ba(2)Mg(BO(3))(2):Eu,Mn, was synthesized by the solid-state reaction method and its photoluminescence properties were investigated by excitation and emission spectra and decay curves. Its excitation band is extending from 250-450 nm, which is adaptable to the emission band of near-ultraviolet LED chips (350-420 nm). Upon the excitation of 365 nm light, the phosphor exhibits strong red emission centered at 615 nm. The relationship between Eu(2+) and Mn(2+) dopants was studied from the viewpoint of a crystal structure and by photoluminescence spectra and decay curves. The results show that the characteristic Eu(2+) emission predominate in the emission band and Mn(2+) promote the redistribution of Eu(2+) at the cation sites of the host crystal.
ABSTRACT
AIM: To investigate the relation between the change of serum IL-21 level and other laboratory indexes by detecting serum IL-21 level from patients with primary Sjogren's syndrome (pSS) and explore the role of IL-21 in pSS. METHODS: The level of serum IL-21 from 40 pSS patients diagnosed according to 2002 revised international classification criteria for pSS and 30 healthy persons were detected by enzyme-linked immunosorbent assay(ELISA) respectively. Meanwhile, FT3, FT4, TSH, TgAb, TPOAb were detected by Immunochemiluminescent technique. Double diffusion method, Westergren and automatic gel method detected ant-SSA and ant-SSB antibody, ESR and serum protein electrophoresis respectively. The relationship between serum IL-21 level and other clinical symptom of the patients was analyzed. RESULTS: The level of serum IL-21 in patients with pSS (1051+/-335) ng/L was obviously higher than that in healthy control (466+/-90 ng/L), (P<0.05). The levels of serum IL-21 in the self-antibody positive group, parotid gland swelling pain group, rash group and incorporating hypothyroidism group were higher than those in their negative control groups, and there were significant differences(P<0.05). In addition, The level of serum IL-21 level in pSS patients showed positive correlation with gamma-globulin (r=0.719, P<0.05) and ESR level(r=0.745, P<0.05). CONCLUSION: The evident increase of serum IL-21 level in pSS patients has positive correlation with the levels of gamma-globulin and ESR, which suggests that IL-21 may play a critical role in the pathogenesis of pSS.
Subject(s)
Interleukins/blood , Sjogren's Syndrome/blood , Sjogren's Syndrome/metabolism , Adult , Enzyme-Linked Immunosorbent Assay , Female , Humans , Hypothyroidism/blood , Hypothyroidism/metabolism , Hypothyroidism/pathology , Male , Middle Aged , Sjogren's Syndrome/pathology , Young Adult , gamma-Globulins/metabolismABSTRACT
AIM: To investigate the changes of serum BAFF and IL-21 levels in the patients with systemic lupus erythematosus (SLE) and explore their clinical significance. METHODS: The serum levels of BAFF and IL-21 were detected by enzyme-linked immunosorbent assay (ELISA). RESULTS: The levels of serum BAFF and IL-21 in the patients with SLE were obviously higher than those in healthy control group. The BAFF level in the group of lupus nephritis (LN) with renal biopsy increased with pathologic aggravation and the IL-21 level in II, III, IV LN also increased, with the most obviously change in the type IV. The levels of BAFF and IL-21 obviously increased in SLE patients with Sjogren's syndrome (SS), but the levels of BAFF and IL-21 obviously tended to decrease in the patients after glucocorticosteroid treatment for a week, with the most significant decrease in BAFF. The changes of BAFF and IL-21 were related to major immune indexes in the patients with SLE. There was positive correlation between BAFF and IL-21 in IV LN. CONCLUSION: The levels of serum BAFF and IL-21 level are increased in the patients with SLE. The dysfunction and synergistic effect of T and B lymphocytes play different roles in the patients with different organ damage and pathoprocess respectively.