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Cyclic loading tests for a novel type X-shaped buckling-restrained brace (X-BRB), comprising two unconnected steel plate braces encased in an assembled steel panel or assembled X-shaped restraining members, were carried out to investigate the hysteretic behavior of five X-BRBs. Besides, three diagonal BRBs with similar constructional details were tested for a direct comparison. The effects of configuration and size of restraining members, gaps between the restraining members and plate braces and the distance between bolts on the working behavior were mainly examined. The restraining members were constructed by steel parts or steel-concrete composite parts. Tests reveal that, compared with diagonal BRBs, in-plane gaps between the restraining members and plate braces have direct impacts on the interaction between them in X-BRBs, as well as on the overstrength of X-BRBs after yielding of plate braces. Larger gaps enlarged the amplitudes of residual flexural deformation of plate brace. The maximum strength of each diagonal BRB or X-BRB is much larger than its yield strength due to strain hardening and frictional action, as well as the in-plane interaction in X-BRBs. When appropriate spacing of assembled bolts was ensured, either steel or steel-concrete composite restraining members nearly remained intact. All specimens achieved great ductility and energy dissipation capacity and eventually failed due to tension fracture of the plate braces. Whereas, large spacing of bolts induced local bending failure of restraining members. When two parts of each broken plate brace contacted again under further large drifts, the compressive resistance was revived in some degree. The assembled configuration realized reuse of restraining members and would facilitate inspection or replacement of encased braces in application. In this paper, configurations of assembled steel or steel-concrete composite restraining members were proposed to allow the two encased diagonal braces to pass through each other freely, to improve bearing capacity of restraining members, etc. Moreover, cyclic loading tests for five X-shaped BRBs and three diagonal BRBs were conducted to examine the effects of the constructional details on the hysteretic behavior of the assembled BRBs. The configuration details of the specimens and preparation of tests were introduced first, and then both the test results and evaluation on the hysteretic behavior, failure modes, ductility and energy dissipation, etc. were provided in detail. For example, the test setup with X-shaped BRBs (Fig. 1(a) and (b)) and hysteretic behavior of the specimen XCBRB with steel-concrete composite restraining members (Fig. 1(c)) are as follows. Fig. 1. Test rig installed with the X-shaped BRB specimen and the acquired hysteretic curves. [Display omitted] • New assembled X-shaped buckling restrained braces (XBRBs) were propose and tested. • The assembled XBRBs exhibit stable behavior and good ductility under cyclic loads. • In-plane gaps affect in-plane flexural deformation and interaction of XBRBs. • Appropriate spacing of bolts ensures bearing capacity of restraining members. • Contact between two parts of a broken brace would sustain some compression forces. [ABSTRACT FROM AUTHOR]

A series of Er3+- and Yb3+-doped K2LaNb5O15 (KLN:xEr3+/Yb3+) up-conversion (UC) submicro-particles have been synthesized for the first time by a simple and low-cost molten salt (MS) approach. X-ray diffraction (XRD) was performed to analyze the phase and structure, and the prepared KLN:xEr3+/Yb3+ samples exhibited a single phase tetragonal tungsten bronze (TTB) structure. The morphologies were characterized by scanning electron microscopy (SEM), and submicro-rod-like particles were obtained for all samples. Under 980 nm excitation, KLN:xEr3+/Yb3+ emitted bright green and weak red emissions which arose from the intra-4f transitions of Er3+ ions. The UC emission intensities and RR/G (the intensity ratio between red and green emissions) were disclosed to be tightly dependent on the Yb3+ ion concentration, and the involved UC luminescence mechanism was studied. Meanwhile, the slope of log I–log P plots displayed an evident reduction with a Ts (sintering temperature) increase, which was ascribed to the saturation effect coming from the competition between UC processes and linear decay. Furthermore, temperature-dependent UC behavior and temperature sensing properties of KLN:xEr3+/Yb3+ were probed based on the fluorescence intensity ratio (FIR) technique of UC green emission. The maximum sensor sensitivity (S) of KLN:0.04Er3+/Yb3+ (Ts = 900 °C) and KLN:0.16Er3+/Yb3+ (Ts = 900 °C) was determined to be as high as 10.90 × 10−3 and 12.27 × 10−3 K−1, respectively. We also showed that the particle size has an evident influence on S, which can be qualitatively interpreted by J–O theory. Thermal-cycling measurements were conducted at different temperatures, and good reliability and repeatability were confirmed. In addition, an obvious optical heating effect was also realized and the variation of temperature induced with a laser was about 32 K. These results reveal that KLN:xEr3+/Yb3+ submicroparticles with high sensor sensitivity and an obvious laser-induced thermal effect are suitable for future optical thermometers and optical heaters. [ABSTRACT FROM AUTHOR]

MicroRNA (miRNA) therapeutics are a promising cancer treatment approach with high efficacy and low side effects. Although substantial progress regarding pharmacokinetics and pharmacodynamics of miRNAs is made, it remains challenging for effective and harmless intracellular delivery. In this study, instant and efficient intracellular delivery of miRNA against esophageal cancer via photothermal effects induced on plasmonic pyramid arrays is reported. An instantaneous high temperature can be generated (≈470 °C) on a plasmonic pyramid after laser stimulation (≈8 μs @640 nm), which is enough to disrupt the cell membranes to facilitate intracellular delivery of biocargos like miRNA. Within ≈150 μs after removal of laser stimulation, the pyramid temperature would decrease to ≈37 °C to avoid cell damage. By this approach, intracellularly delivery of miRNA‐185 to Taxol‐resistance esophageal cancer cells is successfully achieved within minutes with decent delivery efficiency (64%) and cell viability (>95%) are observed after optimization. Moreover, for combating drug resistance, 61.9% of KYSE30/Taxol cell is inhibited after laser‐stimulation via the combined effects of miR‐185 and Taxol with efficient intracellular delivery. This study provides a convenient intracellular delivery approach for large biocargos and a possible solution for overcoming cancer drug resistance. [ABSTRACT FROM AUTHOR]

The investigation of the electrical transport properties of ZrS 2 is conducted up to 30.7 GPa using first-principles calculation and electrical experimental methods. The electrical parameters of ZrS 2 are investigated under high pressure conditions using the thin film integrated microcircuit technology on a diamond anvil cell. The structural phase transitions occur at approximately 2.0 GPa and 6.0 GPa, as evidenced by changes in the energy band structure and discontinuities in electrical parameters. At around 12.3 GPa, the pressure-induced metallization is observed by temperature-induced resistivity and the closing of the band gap. The sudden decrease in resistivity can be attributed to the combined contribution of an increase in carrier concentration and mobility. Similarly, the abrupt decrease in Hall coefficient is attributed to the increase in carrier concentration. [Display omitted] • ZrS 2 undergoes two phase transitions by theoretical calculation. • The reversible structural phase transitions causes changes in electronic properties. • Metallization occurs at around 12.3 GPa via temperature-induced resistivity. • The measured electrical parameters confirm the generation of phase transitions. [ABSTRACT FROM AUTHOR]

Abstract: Gaussian-dependence superresolving filter (GSF) is proposed to investigate the three-dimensional focusing properties of superresolving filter regarding a Gaussian beam. The two-zone annular phase filter with its phase-shifted by π is employed to give a specific description. Analytical expressions of performance parameters are derived by taking into account the shape of incident beam. A brief analysis indicates that Gaussian beam with narrower-ring amplitude makes higher demands on the structure of GSF while exhibits superior transverse superresolving and axial apodizing effects. [Copyright &y& Elsevier]

Upconversion (UC) luminescence modulation is quite important in controlling and processing light for active components of light sources, photoswitches, optical memories, and optical sensing devices. In this work, we reported one kind of novel phosphor, Ho3+/Yb3+‐doped SrBi4Ti4O15 ceramics, which displayed both strong UC luminescence and obvious photochromic (PC) reaction. The UC luminescence, PC effect, and the modulation of UC performance based on PC behavior were investigated in detail. By alternating visible light irradiation and thermal stimulus, the UC luminescence could be reversibly regulated. Meanwhile, the modulation was unveiled to tightly rely on the irradiation time and thermal treatment processes. Excellent reproducibility was also achieved. In addition, as an alternative method to thermal treatment, the manipulation of luminescence by electric field was also explored. Finally, the mechanism related to the UC luminescence manipulation was illustrated. The results indicate that these samples could be potentially utilized in optical data storage and anti‐counterfeiting security fields. [ABSTRACT FROM AUTHOR]

The manipulation of luminescence properties of upconversion (UC) materials from micro to macro aspects is of vital importance for disclosing new physical phenomena and expanding the range of applications. In this work, a novel class of SrBi 2 Nb 2 O 9 (SBN)-based inorganic photochromic (PC) phosphors was synthesized, which exhibited intense susceptibility to visible light irradiation. Large reversible UC modulation ability upon PC effect was realized. Besides, the regulation of UC luminescence was discovered to strongly rely on the irradiation time and heating processes. The mechanisms connected to the UC luminescence, PC effect, and UC manipulation were illustrated. These results demonstrated that SBN-based samples owing high reversible manipulation ratio, fast response, low heating temperature, and excellent reproducibility can be employed as a type of ideal optical medium for future information storage device. In addition, based on the reversible behavior of photochromism, the application of the SBN-based ceramic as an anti-counterfeiting agent was also depicted. [ABSTRACT FROM AUTHOR]

Photoluminescence materials with reversible luminescence regulation properties have great potential for applications in photoswitches, optical sensing, and high-density optical data storage devices. In this work, a series of Pr3+-doped Bi 4 Ti 3 O 12 (BiT) ceramics were synthesized by a high-temperature solid-phase reaction method. It is well known that BiT is the most famous one within the Aurivillius ferroelectric (FE) system. Previous works routinely focused on the FE-related properties of BiT-based compounds, but little attention has been devoted to the luminescence, especially the luminescence modulation performance. Here, a large and reversible photoluminescence modulation by alternating visible light irradiation and thermal stimulus based on photochromic (PC) process was achieved. Meanwhile, the influence of sintering temperature on the luminescence modulation behavior was also illustrated. The luminescence regulation properties of the Pr3+-doped BiT ceramics prepared at optimized sintering temperature were investigated in detail. The mechanisms connected to the luminescence, luminescence manipulation, and PC effect were discussed. It is believed that Pr3+-doped BiT materials can be utilized as a kind of ideal optical medium for future information storage device. [ABSTRACT FROM AUTHOR]

Wearable electroenzymatic sensors enable monitoring of clinically informative biomolecules in epidermally retrievable biofluids. Conventional wearable enzymatic sensors utilize Prussian Blue (a redox mediator) to achieve selectivity against electroactive interferents. However, the use of Prussian Blue presents fundamental challenges including: 1) the susceptibility of the sensor response to dynamic concentration variation of ionic species and 2) the poor operational stability due to the degradation of its framework. As an alternative wearable electroenzymatic sensor development methodology to bypass the aforementioned limitations, a mediator‐free sensing interface is devised, comprising of a coupled platinum nanoparticle/multiwall carbon nanotube layer and a permselective membrane. The interface is adapted to develop sensors targeting glucose, lactate, and choline (as examples of informative metabolites and nutrients), showing high degrees of sensitivity, selectivity (against a wide panel of naturally present and diverse interfering species), stability (<6.5% signal drift over 20 h operation), and reliability of sensing operation in sweat samples. By integration within a readout board, a wireless sample‐to‐answer system is realized for on‐body sweat biomarker analysis. This methodology can be adapted to target a wide panel of biomarkers in various biofluids, introducing a new sensor development direction for personal health monitoring. [ABSTRACT FROM AUTHOR]

Up-conversion (UC) phosphors with multiple functions are highly desirable for many potentially technological applications which can stimulate the miniaturization and multipurpose of modern devices. In this work, Tm3+- and Yb3+-codoped SrBi 4 Ti 4 O 15 (SBT:xTm3+/Yb3+) nanoparticles have been first synthesized by a convenient EDTA-citrate method. The structures and morphologies of SBT:xTm3+/Yb3+ were measured by powder X-ray diffraction, Fourier transform infrared reflectivity spectra and scanning electron microscope. Under 980 nm excitation, SBT:xTm3+/Yb3+ exhibited strong near-infrared (NIR) and weak visible emissions. The UC emissions were unveiled to be tightly related to the Tm3+ concentration and the optimum concentration was determined as x = 0.01. The possible UC mechanism was proposed. Importantly, based on thermo-responsive fluorescence intensity ratio approach, the optical thermometric properties were characterized in the temperature range between 313 and 573 K. The maximum sensitivity of SBT:0.01Er3+/Yb3+ UCNPs was obtained as 7.5 × 10−4 K-1. Besides, excellent repeatability and stability were also realized by the thermal-cycling measurement. Furthermore, prominent photo-thermal (PT) effect was also achieved with a temperature coefficient being 0.81 °C∙mm2/mW. Under periodic laser stimulation, the PT effect of the sample displayed regular response, indicating that the PT effect can be expediently controlled by 980 nm laser. These results indicate that SBT:xTm3+/Yb3+ UCNPs could be potential candidates for temperature sensors and PT agents. [ABSTRACT FROM AUTHOR]

Abstract Up-conversion (UC) oxides comprise a huge family of materials with abundant optical functionalities and they merit extensive research. Some members of this family have been modified with proper rare earth (RE3+) ions and their importance has recently been established in non-contact temperature sensors, although the thermal sensitivity (S) value was still low. In this study, we investigated Nd3+ and Yb3+ sensitized Ba 4 La 2 Ti 4 Nb 6 O 30 (BLTN:xNd3+/Yb3+) with a tungsten bronze structure for use as optical thermometers for the first time. Under excitation at 980 nm, obvious near-infrared emissions corresponding to 4F 7/2 /4S 3/2 → 4I 9/2 , 4F 5/2 /2H 9/2 → 4I 9/2 , and 4F 3/2 → 4I 9/2 transitions were observed, and the UC mechanism involved was elaborated. Furthermore, the UC thermometric properties were investigated according to the fluorescence intensity ratio technique and the maximum S values determined for BLTN:xNd3+/Yb3+ (x = 0.12 and 0.16) samples were both higher than 0.03 K–1. The potential of BLTN:xNd3+/Yb3+ for use in optical thermometers was estimated based on comparisons with other active materials. Highlights • Tungsten bronze material used as an optical thermometry host material. • Novel BLTN:xNd3+/Yb3+ samples synthesized via a simple solid state reaction. • Structure, up-conversion, and temperature sensing behavior investigated. • Sensitivities of BLTN:xNd3+/Yb3+ (x = 0.12 and 0.16) higher than 0.03 K–1. [ABSTRACT FROM AUTHOR]

Detection of analytes by means of field-effect transistors bearing ligand-specific receptors is fundamentally limited by the shielding created by the electrical double layer (the “Debye length” limitation). We detected small molecules under physiological high–ionic strength conditions by modifying printed ultrathin metal-oxide field-effect transistor arrays with deoxyribonucleotide aptamers selected to bind their targets adaptively. Target-induced conformational changes of negatively charged aptamer phosphodiester backbones in close proximity to semiconductor channels gated conductance in physiological buffers, resulting in highly sensitive detection. Sensing of charged and electroneutral targets (serotonin, dopamine, glucose, and sphingosine1-phosphate) was enabled by specifically isolated aptameric stem-loop receptors. [ABSTRACT FROM AUTHOR]

The rapid development of fluorescence imaging technologies requires concurrent improvements in the performance of fluorescent probes. Quantum dots have been extensively used as an imaging probe in various research areas because of their inherent advantages based on unique optical and electronic properties. However, their clinical translation has been limited by the potential toxicity especially from cadmium. Here, a versatile bioimaging probe is developed by using highly luminescent cadmium-free CuInSe2/ZnS core/shell quantum dots conjugated with CGKRK (Cys-Gly-Lys-Arg-Lys) tumor-targeting peptides. This probe exhibits excellent photostability, reasonably long circulation time, minimal toxicity, and strong tumor-specific homing property. The most important feature of this probe is that it shows distinctive versatility in tumor-targeted multimodal imaging including near-infrared, time-gated, and two-photon imaging in different tumor models. In a glioblastoma mouse model, the targeted probe clearly denotes tumor boundaries and positively labels a population of diffusely infiltrating tumor cells, suggesting its utility in precise tumor detection during surgery. This work lays a foundation for potential clinical translation of the probe. [ABSTRACT FROM AUTHOR]

Instant Intracellular Delivery of miRNA via Photothermal Effect Induced on Plasmonic Pyramid Arrays (Adv. Funct. Keywords: esophageal cancer; miRNA; photothermal effects; SPR; taxol-resistance EN esophageal cancer miRNA photothermal effects SPR taxol-resistance 1 1 1 02/24/22 20220223 NES 220223 B Intracellular miRNA Delivery b In article number 2107999, Zhen Fan, Xiaobin Xu, and co-workers report using scanning laser stimulation to generate instantaneous high temperature on plasmonic pyramid arrays to disrupt the cell membranes to facilitate intracellular delivery of biocargos like miRNA. Esophageal cancer, miRNA, photothermal effects, SPR, taxol-resistance. [Extracted from the article]

Three tetra-aryl substituted 1,3-butadiene derivatives with aggregation enhanced emission (AEE) and mechanochromic fluorescence behavior have been rationally designed and synthesized. The results suggest an effective design strategy for developing diverse materials with aggregation induced emission (AIE) and significant mechanochromic performance by employing D-π-A structures with large dipole moments. [ABSTRACT FROM AUTHOR]

The upconversion (UC) luminescence tuning of phosphors has attracted increasing interest as optical switches, optical sensing, and high-density optical data storage devices. However, the design and synthesis of photo-switchable inorganic luminescent materials were still at primary stage. In this work, a new type of UC luminescence regulation materials, Er3+-activated tetragonal tungsten bronze Ba 0.7 Sr 0.3 Nb 2 O 6 ferroelectrics, showing strong susceptibility to visible light irradiation, was reported based on non-photochromic (N-PC) effect. Under visible light irradiation, the maximum luminescent modulation ability reached up to 79.4%. The tuning of UC luminescence was disclosed to tightly rely on the irradiation time and thermal treatment processes. Meanwhile, excellent reproducibility was also demonstrated. Besides, the luminescent readout almost had no any influence on the UC emission, indicating the extremely low destruction to the stored luminescent states. The mechanisms related to the UC luminescence and manipulation were also discussed. In contrast to the previous tuning way based on PC reaction, it is believed that this work shed new light for the understanding of UC modulation fundamentals. Graphical abstract of our paper "A new class of upconversion luminescence tuning materials based on non-photochromic reaction: Er-activated Ba 0.7 Sr 0.3 Nb 2 O 6 ferroelectrics" is as follow. UC spectra and photographs of BSN: xEr3+ (x=0.2) sample before and after LD irradiation. Image, graphical abstract [ABSTRACT FROM AUTHOR]

Up-conversion nanoparticles (UCNPs) stimulated by near-infrared (NIR) light have received immense interest for their potential applications in many fields. In this work, Nd3+- and Yb3+-sensitized Bi 4 Ti 3 O 12 (BiT x :Nd3+/Yb3+, 0.005 ≤ x ≤ 0.3) UCNPs with thermometric and photo-thermal (PT) functions were successfully synthesized by a convenient co-precipitation approach, and the phase and morphologies were characterized. Under 980 nm excitation, BiT x :Nd3+/Yb3+ UCNPs exhibited remarkable multiple emissions in the region from 450 to 900 nm. The visible and NIR emissions were tightly dependent on the Nd3+ concentration and the strongest NIR emissions were obtained in sample BiT0.3:Nd3+/Yb3+. The possible UC mechanisms and processes were proposed. Furthermore, the capability of the UCNPs as thermometers was probed based on the thermo-responsive fluorescence intensity ratio technique in the temperature range 303–573 K. The maximum sensitivity (S max) of BiT0.3:Nd3+/Yb3+ was determined to be as high as 0.032 K-1. Meanwhile, PT effect was evaluated by monitoring the variation of surface temperature of the sample as functions of irradiation time and power density. Conspicuous PT effect was confirmed and the maximum temperature induced by laser was about 91 °C. These results reveal that BiT0.3:Nd3+/Yb3+ UCNPs has promising potential applications as optical thermometer and heater. • BiTx:Nd3+/Yb3+ UCNPs were synthesized by a facile co-precipitation method. • UC properties were investigated and the corresponding mechanism was discussed. • Relying on FIR technique, thermometric properties were studied. • Sensor sensitivity as high as 0.032 K−1 was achieved. • Prominent PT effect was obtained and the induced temperature was about 91 °C. [ABSTRACT FROM AUTHOR]

Electroenzymatic Sensors: A Mediator-Free Electroenzymatic Sensing Methodology to Mitigate Ionic and Electroactive Interferents' Effects for Reliable Wearable Metabolite and Nutrient Monitoring (Adv. Funct. Keywords: electrochemical sensors; mediator-free sensors; metabolite monitoring; nutrient monitoring; wearable biomarker sensors Electrochemical sensors, mediator-free sensors, metabolite monitoring, nutrient monitoring, wearable biomarker sensors. [Extracted from the article]