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Up-to-date laser-driven lightings confront a challenge of simultaneously achieving good photometric and chromatic performances. Herein, the coupling of “patterned package design” and “phosphor wheel” was proposed and demonstrated effectively to deal with this tough issue, based on a new architecture of CaAlSiN3:Eu2+ (CASN:Eu) glass ceramic film (GCF) on Y3Al5O12:Ce3+ (YAG:Ce) GC plate. The fabricated composite has no interface between the two functional layers and retains the admirable luminescent features from CASN:Eu and YAG:Ce for the microstructural integrity during co-sintering. The studies on laser-microcrystalline interactions reveal that the luminescence saturation is almost determined by thermal quenching for YAG:Ce, but is ascribed to thermal/intensity quenching which are equally crucial for CASN:Eu. Benefiting from the elaborate architecture design, good color chromaticity tunability was obtained, and severe photon reabsorption was reduced. Moreover, accompanied with the rotation induced increase of thermal convection to air and pulse-like excitation, the constructed lighting engine under blue laser driven shows bright white light with luminous flux (LF) higher than 1000 lm, adjustable chromaticity from cool to warm, and improved color rendering index (CRI) approaching to 70.

A newly five-component equimolar high-entropy ceramic – (La0.2Eu0.2Gd0.2Y0.2Yb0.2)2Zr2O7 with a mixture phase of pyrochlore and fluorite structure was successfully synthesized. On this basis, a series of systematically designed and synthesized high or medium-entropy ceramics, accompanied by a large number of previous reports on multi-component rare earth zirconates, were summarized to jointly investigate the single-phase forming ability of high-entropy rare earth zirconates ceramics (HE-RE2Zr2O7 for short) in terms of entropy value and cationic radius difference ( δ ). Subsequently, the forming process and mechanism of dual-phase solid solution were analyzed. The conclusions indicated that the single-phase forming ability was more determined by the cationic radius difference rather than the entropy value，and the critical value of δ distinguishing single-phase between dual-phase zone was around 5.2%. In addition, the formation of dual-phase solid solution was essentially driven by the size disorder resulting from rattler effect of cations with significant difference in radius. This work is the first report on the single-phase forming ability of HE-RE2Zr2O7 and would pave new ways for predicting the formation of high-entropy phases.

With the proliferation of the use of wireless communication technologies, lightweight, easily fabricated electromagnetic wave (EMW) absorbers are in great demand for commercial and stealth applicationS In this paper, well-defined Cu2O microcubes were successfully converted into S-doped Cu2 − xSe micro-cubic boxes at room temperature by a template-directed in situ selenization/sulfidation reactioN the Cu2 − xSe boxes were obtained under the combined effect of Kirkendall effect and Ostwald ripening, and the composite products with paraffins exhibited good EMW low-frequency absorption properties at 40 wt%, with RL(min) exceeding − 20 dB from 2.6 mm-5.0 mM In addition, the sulfidation process optimized the morphology, composition, interface, defects, and conductivity, which further enhanced the EMW absorption performance of the materiaL The optimized RL(min) of S-doped Cu2 − xSe reaches − 44.5 dB at 1.9 mm with an EAB of 4.3 GHZ

Improving urban comprehensive carbon emission performance (CCEP) is the inevitable choice for China’s low-carbon development. With the continuous integration of digital technology and financial elements, the development of urban digital finance has also been significantly improved. To further explore the impact of urban digital finance on urban low-carbon development, using the data of 281 cities in China from 2011 to 2019, this paper firstly evaluates the urban CCEP, and further empirically investigates how digital finance influences CCEP. The empirical results show that: (1) Digital finance significantly improves the urban CCEP, and after conducting robustness tests and addressing the endogeneity issue, the above conclusion is robust. (2) For the sub-indicators, there is a U-shaped relationship between the coverage breadth of digital finance and CCEP. Moreover, the improvement of usage depth and digital support services could promote CCEP. (3) The channel tests indicate that digital finance improves the CCEP mainly by promoting green technology innovation and the development of urban tertiary industry. Meantime, digital finance has a stronger impact on improving CCEP in cities with more developed traditional finance, and the positive effect is significant in non-old industrial base cities and a two-control zone. Finally, this paper puts forward relevant policy suggestions.

For Chen-Qi-like four-dimensional hyper-chaotic system, controllers designed with Lyapunov stability theory to achieve synchronous/anti- synchronous control of chaos are found that sometimes synchronization errors do not decrease to zero in finite time. To solve it, a new controller and parameter estimation law are proposed to achieve finite-time synchronization. The stability analysis of the closed-loop dynamics is derived and the effectiveness of the theoretical results is testified. Taking the parameters L=2, μ=0.5, the state time history diagram and the synchronous error curve are investigated via numerical simulation, which show that the synchronization errors are zero in finite time while two systems in chaotic motion, but synchronization error of the state with cubic nonlinearity is not zero in finite time while two systems in periodic motion; Adjust L=200,μ=0.5, numerical simulation again, then all the errors are zero in finite time. Thus the effectiveness is verified.

Lanthanide up-conversion features stepwise multi-photon processes, where the difference in photon number that is required for specific up-conversion process usually leads to significant variance in pumping-related processes/properties. In this work, a pumping-controlled dual-mode anti-counterfeiting strategy is conceived by taking advantage of the combination of up-conversion processes with different photon numbers. The combination of Er3+ and Tm3+, which are spatially separated within a designed core/triple-shell nano-architecture, is taken as an example to illustrate such idea. Upon infrared excitation, the emission color of a designed pattern can be switched from red to purple by increasing the excitation power density from 5 to 11 W/cm2, while a bright luminescent trajectory including red, white and blue-green color with different length is observed when rotating the pattern above 600 rpm. In addition, the relative up-conversion emission intensities of the Er3+ and Tm3+ ions can be manipulated through tailoring interfacial or inner defects in the core/triple-shell nano-crystals, which enable an ultrahigh sensitivity for the pumping-controlled emission color variation to be observed under excitation power well below 11 W/cm2.

Last decade has witnessed the unique ability of localized surface plasmon resonance nanostructure to significantly enhance upconversion luminescence efficiency of lanthanide ions, which has been demonstrated in terms of either increased absorption cross section or accelerated radiative decay rate (Purcell effect) induced by the concentrated electromagnetic field. Herein, we report the upconversion luminescence enhancement of NaGdF4:Yb/Er by dual plasmonic Au–CuS heterodimer nanocrystals, where both the local field enhancement effect and Purcell effect, initialized by different parts of the heterodimer, contribute jointly to the enhancement of upconversion emissions. This work provides the possibility to implement LSPR-based enhancement of upconversion luminescence by metal–semiconductor dual plasmonic antennas, where the judicious combination of active LSPR wavelengths can be manipulated via geometrical design of hetero-nanostructure.

The launch of the big data era puts forward challenges for information preservation technology, both in storage capacity and security. Herein, a brand new optical storage medium, transparent glass ceramic (TGC) embedded with photostimulated LiGa5O8: Mn2+ nanocrystals, capable of achieving bit-by-bit optical data write-in and read-out in a photon trapping/detrapping mode, is developed. The highly ordered nanostructure enables light–matter interaction with high encoding/decoding resolution and low bit error rate. Importantly, going beyond traditional 2D optical storage, the high transparency of the studied bulk medium makes 3D volumetric optical data storage (ODS) possible, which brings about the merits of expanded storage capacity and improved information security. Demonstration application confirmed the erasable–rewritable 3D storage of binary data and display items in TGC with intensity/wavelength multiplexing. The present work highlights a great leap in photostimulated material for ODS application and hopefully stimulates the development of new multi-dimensional ODS media. An optical data storage (ODS) system that is cost-effective to make and easily scalable could lay the foundations for data storage technologies with higher capacity and improved security. The era of big data is driving the need for data storage systems with larger capacity, better security and improved performance. However, even the latest two-dimensional optical disk technologies cannot store more than one terabyte of data, leading scientists to explore alternative technologies. Now, a team of Chinese researchers, led by Yuansheng Wang from the Chinese Academy of Sciences, has developed a three-dimensional ODS system that uses light-emitting nanocrystals (NCs) to store and retrieve information. Made from a transparent glass ceramic embedded with photostimulated luminescent rare-earth-doped metallic NCs, the new ODS system can store 3D optical data with increased capacity and improved security compared with current technologies.

Background: GABAergic deficits have been considered to be associated with the pathophysiology of schizophrenia, and hence, GABA receptors subtype A (GABAARs) modulators, such as commonly used volatile anesthetic sevoflurane, may have therapeutic values for schizophrenia. The present study investigates the therapeutic effectiveness of low-concentration sevoflurane in MK801-induced schizophrenia-like mice and schizophrenia patients. Methods: Three weeks after MK801 administration (0.5 mg kg-1, i.p. twice a day for 5 days), mice were exposed to 1% sevoflurane 1hr/day for 5 days. Behavioral tests, immunohistochemical analysis, western blot assay, and electrophysiology assessments were performed 1-week post-exposure. Ten schizophrenia patients received 1% sevoflurane 5 hrs per day for 6 days and were assessed with the Positive and Negative Syndrome Scale (PANSS) and the 18-item Brief Psychiatric Rating Scale (BPRS-18) at week 1 and week 2. Results: MK801 induced hypolocomotion and social deficits, downregulated expression of NMDARs subunits and postsynaptic density protein 95 (PSD95), reduced parvalbumin - and GAD67-positive neurons, altered amplitude and frequency of mEPSCs and mIPSCs, and increased the excitation/inhibition ratio. All these changes induced by MK-801 were attenuated by sevoflurane administration. Six and eight patients achieved a response defined as a reduction of at least 30% in the PANSS total score at 1st and 2nd week after treatments. The BPRS-18 total score was found to be significantly decreased by 38% at the 2nd week (p < 0.01). Conclusion: Low-concentration sevoflurane effectively reversed MK801-induced schizophrenialike disease in mice and alleviated schizophrenia patients’ symptoms. Our work suggests sevoflurane to be a valuable therapeutic strategy for treating schizophrenia patients.

NASICON-type Na3V2(PO4)3 is a promising cathode for sodium-ion batteries owing to its low cost and great thermal stability as well as high energy density, which has attracted ever growing attention. Nevertheless, the pure Na3V2(PO4)3 possesses a bad electrical conductivity, which hinders its Na+-storage performance for energy storage. Designing and fabrication of the phosphorus-doped graphene-decorated Na3V2(PO4)3@C nanocomposite is performed in this research by a simple and rapid method. The constructed network by phosphorus-doped graphene sheet and carbon layer can greatly strengthen the electron and ionic conductivities of Na3V2(PO4)3, leading to outstanding rate capacity together with cyclic property. The as-fabricated electrode shows a specific capacity of 110.6 mAh g−1 at 0.5 C and a high capacity retention of 91.2% over 500 cycles at 20 C. Therefore, this designed nanocomposite is thought as a prospective cathode for batteries that utilize sodium ion as the charge carrier.

Assessing the demand hazards of structures is requested in the framework of performance-based earthquake engineering. An efficient method for estimating the seismic risk of structures is proposed in this paper. The relationship between multiple limit capacities and corresponding response parameters is denoted by using a generalized multidimensional limit state equation. The limit states of different components are described as random and convex mixed variables. The seismic responses of different components are considered dependent and follow a multidimensional lognormal distribution. The mathematical formula of multidimensional demand hazards of structures is then derived through combining the seismic fragility function and the seismic hazard curve. The proposed method is used to perform the demand hazard analysis and the parameter sensitivity analysis of a multispan continuous concrete girder bridge, selecting column ductility and bearing displacement as the two-dimensional seismic response parameters obtained by Incremental Dynamic Analysis. The results demonstrate that the coefficient of variation and correlation coefficient N, which are involved in the limit state equation, have an impact on the evaluation of the demand hazards.

Intrinsic defect engineered semiconductor photocatalysts have been widely investigated for reaching visible light active photocatalytic H2 production. However, these defects are usually not stably present, thus requires external elements for stabilization. In this paper, we demonstrate a new strategy for significantly enhancing the photocatalytic H2 conversion efficiency. The strategy is based on synergistic effect of the properly rearranged sulfur interstitials and sulfur vacancies without introducing any external dopants. Toward this, the defective Zn2In2S5 nanosheets are successfully synthesized by a simple hydrothermal method. The synergetic contribution of the rearranged sulfur vacancies and sulfur interstitials within the material is strongly supported by that the photo-generated charge-carrier separation efficiency is obviously (∼2-fold) enhanced, and the activity for H2 production at the end of the fourth cycle test is 13-fold more than that of the beginning of the first cycle test. The rearranged positively charged sulfur vacancies and negatively charged sulfur vacancies in-situ form defect associates, which possess electric filed. We propose that the electric filed could effectively separate the photo-generated charge-carriers, and the positively charged sulfur vacancies act as trapping centers for splitting H2O via capturing O atoms into vacancy sites. The trapped O atoms can be subsequently removed by Na2S sacrificial reagent to reactivate the sulfur vacancies. Internally consistent reaction mechanism is proposed that describe the synergistic contribution of the rearranged sulfur vacancies and sulfur interstitials to the dramatically enhanced activity for photocatalytic H2 production. This inspires new design of defective semiconductor materials.

Based on the provincial panel data of China from 2001 to 2016, this study uses the social network analysis approach to empirically investigate the characteristics and driving factors of the spatial association network of China’s interprovincial renewable energy technology innovation. The findings are as following. 1) The spatial association of China’s interprovincial renewable energy technology innovation exhibits a typical network structure. Moreover, its network density, network hierarchy and network efficiency are 0.3696, 0.6667 and 0.7833 in 2001 and 0.4084, 0.4764 and 0.7044 in 2016, respectively, implying the spatial association network became more and more complex and the interprovincial association strengthened during the sample period. 2) This spatial association network presents a “core-edge” distribution pattern. The positions and roles of various provinces vary greatly in the spatial association network. Specifically, the developed coastal regions such as Shanghai, Beijing and Tianjin have a degree centrality, closeness centrality and betweenness centrality of above 75, 80 and 10, respectively, indicating that they always play a central role in the network. However, the northeastern regions and the relatively backward central and western regions such as Heilongjiang, Jilin, Xinjiang, Hainan and Hebei only have a degree centrality, closeness centrality and betweenness centrality of below 20, 55 and 0.1, respectively, indicating that they are at a relatively marginal position. 3) The geographical proximity and the expansion of the differences in economic development level and R&D inputs are conducive to the enhancement of the spatial association of China’s renewable energy technology innovation.

Taking nickel-based single crystal superalloy DD6 as the research object, different degrees of creep damage were prefabricated by creep interruption tests, and then the creep damage was repaired by the restoration heat treatment system of solid solution heat treatment and two-stage aging heat treatment. The results show that with the creep time increasing, the alloy underwent microstructure evolution including γ′ phase coarsening, N-type rafting and de-rafting. After the restoration heat treatment, the coarse rafted γ′ phase of creep damaged specimens dissolved, precipitated, grew up, and became cubic again. Except for the specimens with creep interruption of 100 h, the γ′ phase can basically achieve the same arrangement as the γ′ phase of the original sample. The comparison of the secondary creep test shows that the steady-state creep stage of the test piece after the restoration heat treatment is relatively increased, and the total creep life can reach the same level as the primary creep life. The high temperature creep properties of the tested alloy are basically recovered, and the restoration heat treatment effect is good.

Sound is an important aspect in working environment, and underground strong noise environment imposes a serious impact on operators' physical and mental health and easily leads to people's unsafe behaviors, thus giving rise to accidents. How to quantitatively study operators' behavioral reliability is a study hotspot. To mitigate the noise impact on operators and reduce the occurrence rate of accidents due to human factors, the relational models between noisy working environment and human physiological indexes were established first through a laboratory simulation, and then a reliability integral model was obtained using performance function and limit state equation. Second, the established reliability integral model was numerically simulated based on Monte Carlo numerical simulation method to obtain its numerical solution, and operators' behavioral reliability values under different sound pressure levels (SPLs) on fully-mechanized coal mining face were calculated. The results show that the behavioral reliability of fully-mechanized coal mining operators is high with low accident occurrence rate under noise SPL of 50-70 dB. Under 70-90 dB, their behavioral reliability is 0.7092 with potential accident risks. The behavioral reliability is low when SPL is 90-110 dB, under which accidents may easily take place. This study manifests that operators' behavioral reliability analysis under underground noise environment based on Monte Carlo method is of certain feasibility. The conclusions have a certain guiding significance for relieving human physical and mental harms incurred by noise, improving human behavioral reliability, reducing human errors and guaranteeing safety production.

Magnesium oxychloride (MOC) cement as viable substrate candidate has unique applications in a range of functional and novel sensing applications due to their low thermal conductivity, high toughness, durability and excellent fire resistance. Here, we developed a facile strategy to fabricate metallized patterns on MOC cement composites through laser-induced selective metallization. The laser sensitiser of copper hydroxyl phosphate [Cu2(OH)PO4] was incorporated into MOC cement to prepare MOC cement composites. Then, the metallized copper patterns were obtained on MOC cement composites after 1064 nm pulsed laser activation and electroless copper plating (ECP). The obtained copper layer on MOC cement composites exhibited high electrical conductivity and excellent mechanical adhesion to the substrate. Furthermore, the rough copper patterns exhibited self-cleaning ability after superhydrophobic modification, which could prevent the surface from being contaminated. The metallized copper pattern could rapidly heat up when energised due to the Joule heating effect, and it can be applied for electric heating and automatic deicing in winter. In addition, a UV photodetector was fabricated by designing an interdigital metallized pattern combined with the UV light response characteristics of nano-ZnO, which has potential application on intelligent functional devices.

A linear optimal regulator for uncertain system is designed through the application of the probability density evolution method to linear quadratic regulator controller. One important background of this work is bridge-vehicle/gun-projectile system. This type of optimal problem is currently transformed into a moving load problem. The developed optimal regulator can provide the law of probability densities of outputs varying with time. In order to make the advocated method reach an optimal performance, the beneficial weighting matrix pair (Q, R) is selected using a trade-off sense. The designed regulator is then applied to a coupled simply supported beam-moving mass system, choosing the mid-span deflection as an output response and considering stochastic system parameters. The numerical example shows that the robustness of the proposed optimal regulator cannot be overestimated in comparison with a deterministic linear quadratic regulator controller. Further, the proposed method can produce an efficient solution channel for modern optimal control theory, especially, when compared with different uncertain optimal control techniques.

GABAergic deficits have been considered to associate with the pathophysiology of schizophrenia and hence GABA receptor subtype A (GABAARs) modulators may have therapeutic values for schizophrenia. Sevoflurane, a commonly used volatile anesthetic, enhances GABAergic neurotransmission through the GABAAR. The present study aims to investigate the therapeutic effectiveness of low-concentration sevoflurane in MK801-induced schizophrenia-like mice and amongst schizophrenia patients in a single arm trial. Three weeks after administration of MK801 (0.5 mg/kg, i.p. twice a day) for five days, mice were exposed to 1% sevoflurane for 1 hr/day for 5 days. One week after treatment, they were subjected to behavioral tests, and then sacrificed for immunohistochemical stain, western blot assay and electrophysiology recordings in the prefrontal cortex. Ten schizophrenia patients received 5-hr sevoflurane (0.5–1.2%) for 6 days, and were assessed with the PANSS and the BPRS-18 in the 1st and 2nd week after the treatments. MK801 induced hypolocomotion and social deficits, downregulated the expression of NMDARs subunits, and postsynaptic density protein 95 (PSD95), reduced parvalbumin- and GAD67-positive neurons, and changed the amplitude and frequency of mEPSC and mIPSC and evenly increased the excitation/inhibition (E/I) ratio. All these changes induced by MK-801 were attenuated by sevoflurane administration. Schizophrenia symptoms assessed with the scales were significantly improved in the 1st and 2nd week after treatments. Low-concentration sevoflurane inhalation effectively reversed MK801-induced schizophrenia-like disease in mice and alleviated schizophrenia patients’ symptoms. Our work suggested that sevoflurane may be a valuable therapeutic strategy for treating schizophrenia patients.

In this work, a new type of luminescent temperature sensor based on the Sn2+→Mn2+ resonance energy transfer is designed, which shows great potential in high temperature optical thermometry. Using the micro-sized Sn2+/Mn2+:α-Sr2P2O7 phosphor fabricated by carbon reduction method as optical thermometer, the sensitivity in the temperature range of 423 K–623 K is well superior to that for the other micro/nano luminescent temperature sensing materials reported previously, and the maximal absolute sensitivity reaches as high as 0.027 K−1 at 623 K. Analyses of the temperature-dependent photoluminescence spectra and configurational coordinate diagrams for Sn2+:α-Sr2P2O7 and Mn2+:α-Sr2P2O7 indicate that the temperature-sensitive variation in fluorescence intensity ratio of Sn2+ to Mn2+ is originated from the difference in thermal quenching activation energy for 3PJ (J = 0,1) levels of Sn2+ (4053 cm−1) and 4T1 level of Mn2+ (2464 cm−1). These results may provide useful inspiration for building highly sensitive self-referencing optical thermometers based on energy transfer induced sensitized luminescence.

Surface-modified semiconductors show enormous potential for opto-terahertz (THz) spatial modulation due to their enhanced modulation depth (MD) along with their inherent broad bandwidth. Taking full advantage of the surface modification, a performance-enhanced, all-optical, fast switchable THz modulator was achieved here based on the surface-passivated GaAs wafer. With a decreased surface recombination rate and prolonged carrier lifetime induced by passivation, S-passivated GaAs was demonstrated as a viable candidate to enhance THz modulation performance in MD, especially at low photodoping levels. Despite a degraded modulation rate owing to the longer carrier lifetime, this passivated GaAs modulator simultaneously realizes a fast modulation at a 69-MHz speed and as high an MD as ∼ 94 % in a spectral wideband of 0.2–1.2 THz. The results demonstrated a new strategy to alleviate the tradeoff between high MD and speed in contrast to bare surfaces or heterogeneous films/unusual geometry on semiconductors including Si, Ge, and GaAs.

The buckling and post-buckling behaviors of variable stiffness composite laminates (VSCL) with curvilinear fibers were investigated and compared with constant stiffness composite laminates (CSCL) with straight fibers. A VSCL box structure was evaluated under a pure bending moment. The results of the comparative test showed that the critical buckling load of the VSCL box was approximately 3% higher than that of the CSCL box. However, the post-buckling load-bearing capacity was similar due to the layup angle and the immature status of the material processing technology. The properties of the VSCL and CSCL boxes under a pure bending moment were simulated using the Hashin criterion and cohesive interface elements. The simulation results are consistent with the experimental results in stiffness, critical buckling load and failure modes but not in post-buckling load capacity. The results of the experiment, the simulation and laminated plate theory show that VSCL greatly improves the critical buckling load but has little influence on the post-buckling load-bearing capacity.

The launch of the big data era puts forward challenges for information preservation technology, both in storage capacity and security. Herein, a brand new optical storage medium, transparent glass ceramic (TGC) embedded with photostimulated LiGa5O8: Mn2+ nanocrystals, capable of achieving bit-by-bit optical data write-in and read-out in a photon trapping/detrapping mode, is developed. The highly ordered nanostructure enables light–matter interaction with high encoding/decoding resolution and low bit error rate. Importantly, going beyond traditional 2D optical storage, the high transparency of the studied bulk medium makes 3D volumetric optical data storage (ODS) possible, which brings about the merits of expanded storage capacity and improved information security. Demonstration application confirmed the erasable–rewritable 3D storage of binary data and display items in TGC with intensity/wavelength multiplexing. The present work highlights a great leap in photostimulated material for ODS application and hopefully stimulates the development of new multi-dimensional ODS media., Optics: Next generation of optical data storage systems An optical data storage (ODS) system that is cost-effective to make and easily scalable could lay the foundations for data storage technologies with higher capacity and improved security. The era of big data is driving the need for data storage systems with larger capacity, better security and improved performance. However, even the latest two-dimensional optical disk technologies cannot store more than one terabyte of data, leading scientists to explore alternative technologies. Now, a team of Chinese researchers, led by Yuansheng Wang from the Chinese Academy of Sciences, has developed a three-dimensional ODS system that uses light-emitting nanocrystals (NCs) to store and retrieve information. Made from a transparent glass ceramic embedded with photostimulated luminescent rare-earth-doped metallic NCs, the new ODS system can store 3D optical data with increased capacity and improved security compared with current technologies.

For a Si-based all-optical spatial terahertz modulator (STM), an enhanced modulation efficiency under low illumination density would be of great significance to exploit the competence of THz technology in real-world applications. We presented here an implementation of such a device by microtexturing and passivating the Si surface, forming a truncated pyramidal array (TPA). This TPA structure with SiO2 passivating coatings not only decreases light reflectance and expands the active area for THz modulation but also remarkably increases the photogenerated carrier lifetime. These 3-fold benefits render Si-TPA superior to bare-Si with respect to the achievable modulation efficiency, especially at low irradiation power. Furthermore such a Si-TPA device is also more applicable than its counterpart that is only passivated by SiO2 nanocoatings, even though the Si-SiO2 has a slightly increased modulation efficiency. These periodically aligned pyramids resembled as a mesa array significantly suppress the lateral diffusion induced by longer diffusion, resulting in an equivalent resolution of bare-Si. This novel Si-TPA based STM is highly desired for realizing a high-performance THz imager and provides a feasible approach to breaking the trade-off between resolution and modulation efficiency.

Persistent luminescence (PersL) has long commanded the curiosity of researchers owing to the complicated and profound physics behind it. In this work, the PersL mechanism in a new kind of persistent garnet phosphors, Lu2CaMg2(Si1−xGex)3O12:Ce3+, is studied from the new perspective of a “solid-solution” scheme. Different from the conventional study in pursuit of long PersL, we focus on manipulation of afterglow to the millisecond range and tentatively demonstrate its potential to compensate the flickering of the alternating current driven LED (AC-LED) in every AC cycle. Evidently, the tailored host bandgap favors efficient electron charging and facilitates electron detrapping, as well as redeploying trap distribution, which results in a blue light activated afterglow in the millisecond time range, and subsequently a reduced percent flicker of 64.1% for the AC-LED. This investigation is the first attempt to establish the design guidelines for new PersL materials with an adjustable millisecond ranged afterglow, and, hopefully, it paves a pathway to the development of burgeoning low-flickering AC-LED technology.

Eu3+/Ni2+ co-doped transparent glass ceramic containing both hexagonal GdF3 and spinel-like Ga2O3 nano-crystals has been successfully fabricated by melt quenching and subsequent heating. The orderly precipitation of GdF3 and Ga2O3 nano-crystals was discriminated by the X-ray diffraction data and transmission electron microscopy. The incorporation of Eu3+ ions into GdF3 and the selective partitioning of Ni2+ dopants in Ga2O3 were evidenced by the absorption and emission spectra, luminescence decay curves, crystal field calculation, and Judd–Ofelt analysis. Benefitting from the spatial separation, the energy transfer between Eu3+ and Ni2+ was suppressed completely. The distribution related optical properties of Eu3+ and Ni2+ in glass ceramic were investigated in detailed. This work exemplifies a rational design strategy to construct novel multifunctional materials for optical application.

This paper constructs a knowledge-stock indicator to explore the trend of renewable energy technology innovation (RETI) levels across China's provinces during 1997–2015. First, the spatial-temporal evolution is analyzed. Second, the convergence characteristics and patterns are identified through the nonlinear time-varying factor model and the relative transition path curves. Third, the drivers of convergence behaviors are examined. The results are as follows: (i) China's RETI experienced a spurt of development. Its spatial pattern has changed significantly, and the average annual growth rate has also shown spatial differences; (ii) China's provincial RETI level was not converged as a whole during the sample period, but exhibited club convergence characteristics. The 30 provinces eventually converged to three clubs with large differences in average RETI level and annual growth rate; (iii) the provinces with a more optimized industrial structure, a greater R&D investment intensity, and a higher environmental regulation intensity tended to converge to the club with a higher innovation level and growth rate.

All-inorganic cesium lead halide perovskites with high quantum efficiency and narrow emission bandwidth has emerged as a new-generation color converter for wide-color-gamut LCD. Herein, we present the fabrication of this kind of material in a green, time-saving, low cost, and batched way, following the phase transformation from amorphous to crystalline via glass self-crystallization or thermally-/mechanically-driven glass crystallization. A close insight was put into the microstructure-property relationship by making comparison on the samples via different crystallization routes. The CsPbBr3 in glass yields quantum efficiency of ~48% and emission bandwidth of ~30 nm. The color-tunable emission is facilely realized with the introduction of I− species, based on a solid-solution approach. It was demonstrated that the tough issue of poor thermal-/photo-/moisture-stability in perovskites can be well addressed, thanking to the encapsulation of water- and oxygen-impermeable glass matrix. Moreover, a prototype w-LED was fabricated by coupling the CsPbBr3 devitrified glass, the K2SiF6:Mn4+ phosphor-in-glass, with the commercial InGaN blue chip, producing an ultra-wide color gamut of 103.1% NTSC after passing through the commercial RGB color filters.