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This article presents a 40-Gb/s (25.6 GBaud) quarter-rate receiver utilizing three-level pulse amplitude modulation (PAM). The continuous-time linear equalizer (CTLE) with a passive high-pass filter provides a boosting gain of 13 dB at 12.8 GHz. A two-tap data decision feedback equalizer (DFE) and a one-tap edge DFE are included. The phase detector (PD) logic directly controls the digitally controlled oscillator (DCO) to reduce the loop latency. This receiver is fabricated by a 28-nm CMOS process and its area is 0.12 mm2. By using a pseudorandom ternary sequence (PRTS) of $3^{7} - 1$ , this 40-Gb/s receiver compensates the channel loss up to 23-dB loss with a bit error rate (BER) $\lt 10^{-12}$ . The total power consumption of this receiver is 90 mW at 40-Gb/s, which achieves an FoM of 98 fJ/bit/dB.

ABSTRACTStudents from Asian countries form the largest group of mobile international students in Western anglophone countries. Despite research on the mobility experiences of international students to anglophone and non-anglophone countries, there are limited cross-comparative, mixed-method studies exploring the experiences of host language acquisition and usage and how these impact on academic performance and shapes social connectedness. This study contributes further understanding by exploring language acquisition experiences of international university students in Taiwan and Australia, where the language of instruction is not their native language. In the two universities studied, usage levels (general usage, speaking, reading, listening and writing) differed and depended on situational and contextual needs. Those studying in Australia consistently reported higher mean scores of host language usage across three of the five components: listening, reading and writing. Written communication was perceived to be a challenge for both groups during interviews. Overall, students preferred face-to-face classroom learning and highly valued peer support. Information communication and technology use was common in supporting vocabulary and pronunciation. We discuss how the findings of our study inform the types of academic learning support needed, and how these differed, depending on the host language, and student background.

A 36-Gb/s $2\times $ half-baud-rate (THBR) adaptive receiver (RX) is presented. The pattern-based adaptation method for adjusting the frequency response of a continuous-time linear equalizer (CTLE) is proposed. In addition, the reference voltage of the comparators is adapted to enhance the timing margin of the recovered clock in the RX. This THBR adaptive RX is fabricated in TSMC 28-nm CMOS technology with a core area of 0.097 mm2. The measured bit error rate (BER) is less than 10−12 for a 36-Gb/s pseudorandom binary sequence (PRBS) of 27 – 1, when the channel loss is 19 dB at 18 GHz. The total power consumption of this RX is 76 mW with gated adaptation circuits. The calculated figure of merit (FoM) is 2.1 pJ/bit.

A 32-Gb/s $2\times $ half-baud-rate (THBR) clock and data recovery (CDR) circuit is presented by using a phase detector (PD) and a frequency detector (FD). The frequency detection range of the FD is analyzed. This prototype is fabricated in a 28-nm CMOS process with an active area of 0.055 mm2. The measured frequency capture range is 43.7% for a 32-Gb/s pseudorandom bit sequence (PRBS) of 27-1. This proposed CDR circuit achieves a bit error rate of less than $10^{-12}$ under the channel loss of 23 dB at 16 GHz. The total power consumption is 58.6 mW at 32 Gb/s and achieves a figure-of-merit (FoM) of 0.079 pJ/bit/dB.

Plastics have substantial societal benefits, but their widespread use has led to a critical waste management challenge. While mechanical recycling dominates the reuse of post-consumer plastics, it is limited in efficacy, especially for composites. To address this, we propose a direct reprocessing approach that enables the creation of hybrid, long-lasting, and durable composites from difficult-to-recycle plastics. This approach utilizes cold sintering, a process that consolidates inorganic powders through fractional dissolution and precipitation at temperatures far below conventional sintering; these temperatures are compatible with plastic processing. We show that this process can create inorganic-matrix composites with significant enhancements in tensile strength and toughness over pure gypsum, which is commonly found in construction waste. These composites can be recycled multiple times through direct reprocessing with the addition of only water as a processing promoter. This approach to recycling leads to composites with orders of magnitude lower energy demand, global warming potential, and water demand, when compared against common construction products. Altogether, we demonstrate the potential for cold sintering to integrate waste into high-performance recyclable composites.

The scaly-foot snail (Chrysomallon squamiferum) inhabiting deep-sea hydrothermal vents in the Indian Ocean relies on its sulphur-oxidising gammaproteobacterial endosymbionts for nutrition and energy. In this study, we investigate the specificity, transmission mode, and stability of multiple scaly-foot snail populations dwelling in five vent fields with considerably disparate geological, physical and chemical environmental conditions. Results of population genomics analyses reveal an incongruent phylogeny between the endosymbiont and mitochondrial genomes of the scaly-foot snails in the five vent fields sampled, indicating that the hosts obtain endosymbionts via horizontal transmission in each generation. However, the genetic homogeneity of many symbiont populations implies that vertical transmission cannot be ruled out either. Fluorescence in situ hybridisation of ovarian tissue yields symbiont signals around the oocytes, suggesting that vertical transmission co-occurs with horizontal transmission. Results of in situ environmental measurements and gene expression analyses from in situ fixed samples show that the snail host buffers the differences in environmental conditions to provide the endosymbionts with a stable intracellular micro-environment, where the symbionts serve key metabolic functions and benefit from the host’s cushion. The mixed transmission mode, symbiont specificity at the species level, and stable intracellular environment provided by the host support the evolutionary, ecological, and physiological success of scaly-foot snail holobionts in different vents with unique environmental parameters.

The scaly-foot snail (Chrysomallon squamiferum) inhabiting deep-sea hydrothermal vents in the Indian Ocean relies on its sulphur-oxidising gammaproteobacterial endosymbionts for nutrition and energy. In this study, we investigate the specificity, transmission mode, and stability of multiple scaly-foot snail populations dwelling in five vent fields with considerably disparate geological, physical and chemical environmental conditions. Results of population genomics analyses reveal an incongruent phylogeny between the endosymbiont and mitochondrial genomes of the scaly-foot snails in the five vent fields sampled, indicating that the hosts obtain endosymbionts via horizontal transmission in each generation. However, the genetic homogeneity of many symbiont populations implies that vertical transmission cannot be ruled out either. Fluorescence in situ hybridisation of ovarian tissue yields symbiont signals around the oocytes, suggesting that vertical transmission co-occurs with horizontal transmission. Results of in situ environmental measurements and gene expression analyses from in situ fixed samples show that the snail host buffers the differences in environmental conditions to provide the endosymbionts with a stable intracellular micro-environment, where the symbionts serve key metabolic functions and benefit from the host’s cushion. The mixed transmission mode, symbiont specificity at the species level, and stable intracellular environment provided by the host support the evolutionary, ecological, and physiological success of scaly-foot snail holobionts in different vents with unique environmental parameters.

A semi‐analytical model is built based on diffraction theory and human angular resolution to quantitatively evaluate the diffraction effect of transparent displays, including micro‐LED and OLED. By optimizing the pixel structures within a 2×2‐pixel size region, the relative diffraction intensity is reduced by 42% at the 50% aperture ratio regardless ofpixel density.

By tailoring the radiation pattern through cavity effect, together with a compact compound parabolic concentrator, the light efficiency of μLED is increased by 1.9×. Such a high brightness μLED light engine helps to enhance the ambient contrast ratio for AR displays or to reduce the power consumption for VR headsets.

Transparent displays suffer from background image blur due to light diffraction when passing through periodic pixel structures. A simple, reference‐image free and semi‐analytical model based on diffraction theory and human eye's angular resolution is proposed to quantitatively evaluate the diffraction effect of transparent displays. Several factors including object distance, resolution and aperture ratio are analyzed with our model to establish guidelines for minimizing the diffraction effect in transparent displays. By optimizing the pixel structures within a 2 × 2‐pixel size region, the relative diffraction intensity is reduced by 42% at the 50% aperture ratio regardless of pixel density, which is valuable for achieving diffraction‐less high resolution and low aperture ratio transparent displays with current fabrication technologies. A semi‐analytical model is built based on diffraction theory and human angular resolution to quantitatively evaluate the diffraction effect of transparent displays, including micro‐LED and OLED. By optimizing the pixel structures within a 2 × 2‐pixel size region, the relative diffraction intensity is reduced by 42% at the 50% aperture ratio regardless of pixel density.

Lignin and its derivatives composites have received increasing interests in the field of water treatment for the features of eco-friendliness, cost-effectiveness and sustainable regeneration. Herein, a lignin-based aggregate microparticles adsorbent (SLS/PEI/GO-P) was synthesized through a green method for the adsorption of ciprofloxacin (CIP) in water. The composition and structure of SLS/PEI/GO-P were characterized by SEM, TEM, FT-IR, TG, XRD, XPS and N2adsorption-desorption isotherm. The effects of adsorbent dosage, pH, concentration, time, temperature, inorganic salts and HA on CIP adsorption were investigated through batch experiments. The results indicated that the maximum CIP adsorption capacity was 823.3 mg/g with the CIP concentration of 250 mg/L at pH 8 and 30 ℃, which was much higher than that of most reported. The adsorption kinetics followed the pseudo-second-order model, and the adsorption isotherms followed the Langmuir model. The adsorption thermodynamic study indicated that the adsorption process was spontaneous at low temperatures and exothermic. FTIR and XPS analysis indicated that the adsorption mechanism was mainly involved with electrostatic interactions, hydrogen bonding interactions and π-π interactions. After 5 adsorption and hydrothermal regeneration cycles, the adsorption capacity for CIP by the adsorbent decreased only slightly. The adsorbent has the advantages of green preparation process and regeneration method, good adsorption capacity, and high sustainability, which renders it potentially viable in treating real wastewater containing CIP.

To study the effect of stone powder content on the basic mechanical properties of mechanism sand concrete, the effect of stone powder content of 0%, 3%, 5%, 7%, 9%, 12%, and 15% on the cube compressive strength, axial compressive strength, splitting tensile strength, and modulus of elasticity of mechanism sand concrete was studied with mechanism sand in a region of Guangxi. The modulus of elasticity of the concrete with stone powder was predicted by a three-phase composite model. The results show that with the increase of stone powder content, the slump and expansion of mechanism sand concrete show the change law of increasing first and then decreasing. When the stone powder content reaches 9%, the slump and expansibility of the concrete with mechanical sand reach the maximum. With the increase of stone powder content, the compressive strength and splitting tensile strength of mechanism sand concrete show the change law of increasing first and then decreasing. The 7d and 28d compressive strengths and splitting tensile strengths of the concrete reached their maximum values when the stone powder content was 12%. The effective modulus of elasticity of the concrete was calculated by using Voigt upper and Reuss lower limits, generalized self-consistency method and Mori–Tanaka method, and the effective modulus of elasticity calculated by the code and the above three methods were compared with the measured modulus of elasticity. This paper recommends a method for calculating the modulus of elasticity applicable to machine-made sand concrete (or containing stone dust) and verifies its reliability.

Logistics provider selection is a multi-criteria decision-making problem faced by e-commerce companies. Considering the complexity of the problem and the uncertainty of the decision information, an integrated approach of GTOPSIS is proposed for evaluating and selecting the most suitable logistics provider. The GTOPSIS approach integrates the three-parameter interval grey number (T-PIGN) into the technique for order preference by similarity to ideal solution (TOPSIS). It allows decision-makers to use T-PIGN to represent the performance of the alternatives which can retain and utilise the original uncertain assessment information of alternatives to the greatest extent. Besides, the PERT distribution is adopted to weight the three parameters of T-PIGN. A real-life case study is presented to demonstrate the practicality and effectiveness of the GTOPSIS approach.

Lead halide perovskite nanocrystals (PNCs) are emerging as promising light emitters to be actively explored for high color purity and efficient light-emitting diodes. However, the most reported lead halide perovskite nanocrystal light-emitting diodes (PNCLEDs) encountered issues of emission line width broadening and operation voltage elevating caused by the quantum confinement effect. Here, we report a new type of PNCLED using large-size CsPbBr3PNCs overly exceeding the Bohr exciton diameter, achieving ultranarrow emission line width and rapid brightness rise around the turn-on voltage. We adopt calcium-tributylphosphine oxide hybrid ligand passivation to produce highly dispersed large-size colloidal CsPbBr3PNCs with a weak size confinement effect and also high photoluminescence quantum yield (∼85%). Utilizing these large-size PNCs as emitters, we manifest that the detrimental effects caused by the quantum confinement effect can be avoided in the device, thereby realizing the highest color purity in green PNCLED, with a narrow full width at half-maximum of 16.4 nm and a high corrected maximum external quantum efficiency of 17.85%. Moreover, the operation half-life time of the large-size PNCLED is 5-fold of that based on smaller-size PNCs. Our work provides a new avenue for improving the performance of PNCLEDs based on unconventional large-size effects.

Metal halide perovskites are promising semiconductors for next-generation light-emitting diodes (LEDs) due to their high luminance, excellent color purity, and handily tunable band gap. However, it remains a great challenge to develop perovskite LEDs (PeLEDs) with pure red emission at the wavelength of 630 nm. Herein, we report a spectrally stable and efficient pure red PeLED by employing sequential ligand post-treated CsPbI3quantum dots (QDs). The synthesized CsPbI3QDs with a size of ∼5 nm are treated in sequential steps using the ligands of 1-hydroxy-3-phenylpropan-2-aminium iodide (HPAI) and tributylsulfonium iodide (TBSI), respectively. The CsPbI3QD films exhibit improved optoelectronic properties, which enables the fabrication of a pure red PeLED with a peak external quantum efficiency (EQE) of 6.4% and a stable EL emission centered at the wavelength of 630 nm. Our reported sequential ligand post-treatment strategy opens a new route to improve the stability and efficiency of PeLEDs based on QDs.

A judicious strategy was utilized to envision the substantial regio-positional effects of substituents on the photophysical properties of the 2H-chromen-2-one-3-benzothiazole scaffold-based push–pull framework, named 6-X-CUMs. Among them, 6-NEt2-CUMreveals prominent excited-state intramolecular charge transfer with a large change of dipole moment (Δμ ∼ 18.23 D), hence displaying remarkable emission solvatochromism from the green (536 nm in cyclohexane) to far-red region (714 nm in dimethyl sulfoxide) and a high-temperature sensitivity (−0.23 nm °C–1). These, together with unique basicity and acido-/vaporchromism upon acidification elucidated by NMR and photospectroscopic studies, show stark contrast to the conventional 7-NEt2-CUM. The new series of these tailored 6-X-CUMsrepresents a new dimension in tailoring the photophysical properties for the development of a promising class of multistimuli-responsive materials.

To elucidate the molecular mechanism(s) by which methyl salicylate enhances the skin delivery of herbal ingredients with diverse lipophilicity.

Recently, “liquid crystal display (LCD), organic light‐emitting diode (OLED), or micro‐light‐emitting diode (LED): who wins?” is a heated debatable question. In this review article, we provide a comprehensive overview of these three promising display technologies through nine display performance indicators, including ambient contrast ratio, motion picture response time, viewing angle and angular color shift, color gamut, resolution density, power consumption, cost, lifetime, and thin profile and panel flexibility. The advantages and disadvantages of each technology are analyzed, and their future perspectives are discussed. In this review article, we give a comprehensive overview of three promising display technologies (liquid crystal displays [LCDs] with mini‐light‐emitting diode (LED) backlight, organic LED [OLED] displays, and micro‐LED [μLED] displays) through nine display performance metrics, including ambient contrast ratio, motion picture response time, viewing angle and angular color shift, color gamut, power consumption, resolution density, cost, lifetime, and thin profile and panel flexibility. The strengths and weaknesses of each technology are analyzed, and their future perspectives are discussed.

We develop a patterned cholesteric liquid crystal polymer film with reflection and scattering states. By integrating this film into a color‐converted micro‐LED display, the optical efficiency is increased by 2.14x at 90% Rec.2020 color gamut and the average angular color shift δu'v′ is reduced from 0.03 to 0.018.

We propose a patterned cholesteric liquid crystal (CLC) polymer film as a self‐assembled Bragg reflector to enhance the performance of a color‐converted micro‐light‐emitting diode (LED) display system. In the display system, we firstly optimize the device structure of blue LED chip to maintain a high light extraction efficiency and low optical crosstalk. Next, we fabricate several patterned CLC films with feature sizes ranging from 10 to 80 μm. By integrating the patterned CLC film into a color‐conversion micro‐LED display, the optical efficiency is doubled while keeping a color gamut of about 90% Rec. 2020. Finally, we carry out a proof‐of‐concept experiment to validate the functionality of such a patterned CLC film. A patterned cholesteric liquid crystal (CLC) film is demonstrated to enhance the color‐conversion efficiency (CCE) and color gamut of a color‐converted micro‐light‐emitting diode (LED) display. Such a CLC film not only improves the CCE by recycling the leaked blue light but also alleviates the crosstalk between green and blue color filters. As a result, the CCE is doubled at 90% Rec. 2020.

The first palladium-catalyzed halosulfonylation of alkynes with arylsulfonic acid under aerobic conditions was accomplished. This catalytic protocol provides a straightforward and effective synthetic strategy for the assembly of structurally diverse β-halovinyl sulfones architectures with high atom- and step-economy and exceptional functional group tolerance. Notably, ionic liquid plays a crucial role in this catalytic system, which not only acts as an environmentally friendly solvent, but also provides the halide source. In the presence of 1 ​mol % of IPr-Pd-Cin-Cl as the catalyst, a wide range of terminal alkynes and internal alkynes could be excellently tolerated. Particularly, the developed catalytic system could be recycled up to five times and reused without significant loss of catalytic activity.

High-quality host materials are indispensable for the construction in the emitting layer of efficient organic light-emitting diodes (OLEDs), especially in a guest and host system. The good carrier transport and energy transfer between the host and emitters are out of necessity. In this work, a wide bandgap and bipolar organic compound, 2,2′-bis(4,5-diphenyl-(1,2,4)-triazol-3-yl)biphenyl (BTBP), conjugating two electron-transporting triazole moieties on a hole-transporting biphenyl core, was synthesized and characterized. The wide bandgap of 4.0 eV makes the promise in efficient energy transfer between the host and various color emitters to apply as the universal host, especially for blue emitters. The close electron and hole mobilities perform the same order of 10–5cm2·V–1·s–1, identified as bipolar behavior and benefited for carrier balance at low bias. Although carrier transportation belongs to bipolar behavior at a low electrical field, the electron mobility is much faster than the hole one at a high electrical field and belongs to electron-transporting behavior. Employing the BTBPas the host matrix mixed with a phosphor dopant, iridium(III)bis[4,6-di-fluorophenyl-pyridinato-N,C2]picolinate, a high-efficiency sky-blue phosphorescent organic light-emitting diode (OLED) was achieved with a maximum current efficiency of 65.9 cd/A, maximum power efficiency of 62.8 lm/W, and maximum external quantum efficiency of 30.2%.

Objective: This study evaluated the postures of preschool children aged 4-6 in Beijing, compare the physical health levels of children with different physical characteristics, and explore the influence of posture on children's physical fitness. Methods: In this study, children were selected as subjects to study 227 preschool children (122 boys and 105 girls) in Beijing for body posture evaluation and physical fitness assessment. Results: he physical fitness tests pass rate of children aged 4-6 years was 77.6%. The incorrect body posture detection rate of children aged 4-6 years in Beijing reached 63%. The bad body posture of preschool children will have a certain impact on their height growth and physical fitness development. Specifically, the height scores of children with pelvic anterior tilt and knock knees and bow legs are obviously lower than those of children with normal posture (P< 0.05). The children with high and low shoulder problems have obviously lower tennis throwing scores than normal children (P < 0.05). The score of 10m round-srip of children with pelvic tilt was significantly lower than that of normal children (P <0.05). The scores of the children with pelvic anterior tilt were lower than normal children in the 10m round-srip, and showed a very significant difference (P<0.01), and also their scores of the standing long jump, tennis throwing and continuous jumping were obviously lower than normal children (P < 0.05).Conclusion: The detection rate in children with incorrect body posture tends to increase in age and is characterized by a higher proportion of girls than boys and a higher proportion of overweight and obese children than children of normal weight abnormal posture has a significant impact on children's body shape and physical quality. The physical fitness tests pass rate of children has the characteristics that boys are better than girls and decreases with age. The main incorrect body postures with a higher detection rate are knock knees and bow legs (DR=59.5%), high and low shoulders (DR=42.8%), and pelvic anterior tilt(DR=36.1%). Early intervention and specialized education on children's physical fitness and posture through the integration of sports and education are the key educational factors to improve the posture and improve the level of physical fitness. [ABSTRACT FROM AUTHOR]

Ambient light excitation in quantum dots‐converted micro‐LED displays is analyzed and the calculated results agree well with simulations. By depositing a layer of color filter and reducing the area ratio of quantum dots, the display's ambient contrast ratio can be improved to adequately readable under full daylight.

All-inorganic lead halide perovskite nanocrystals (NCs) are potential candidates for fabricating high-performance light-emitting diodes (LEDs) owing to their precisely tunable bandgaps, high photoluminescence (PL) efficiency, and excellent color purities. However, the performance of pure red (630–640 nm) all-inorganic perovskite LEDs is still limited by the halide segregation-induced instability of the electroluminescence (EL) of mixed halide CsPbI3-xBrxNCs. Herein, we report an effective approach to improving the EL stability of pure red all-inorganic CsPbI3-xBrxNC-based LEDs via the passivation of potassium bromide on NCs. By adding potassium oleate to the reaction system, we obtained potassium bromide surface-passivated (KBr-passivated) CsPbI3-xBrxNCs with pure red PL emission and a photoluminescence quantum yield (PLQY) exceeding 90%. We determine that most potassium ions present on the surface of NCs bind with bromide ions and thus demonstrate that potassium bromide surface passivation of NCs can both improve the PL stability and inhibit the halide segregation of NCs. Using KBr-passivated CsPbI3-xBrxNCs as an emitting layer, we fabricated stable and pure red perovskite LEDs with emission at 637 nm, showing a maximum brightness of 2671 cd m–2, maximum external quantum efficiency of 3.55%, and good EL stability. The proposed KBr-passivated NC strategy will open a new avenue for fabricating efficient, stable, and tunable pure color perovskite NC LEDs.

By detecting the severe meteorological situations on flight route, airborne weather radar (WXR) can ensure the safety of the aircraft and on-board personnel. Among these critical weather conditions, atmospheric turbulence is one of the main factors that affect flight safety. Atmospheric turbulence detection method that the current WXR adopts mainly is the pulse pair processing (PPP) method, which estimates Doppler spectrum width of weather target echo and compares it with a threshold to determine whether this weather target is turbulence or not. PPP method is simple and easy to implement, but the performance of this method under the condition of low signal-to-noise ratio (SNR) is poor. In this paper, we propose a new turbulence detection method based on the principal component analysis (PCA) approach. This new method uses PCA approach to preprocess the weather target echo and divides it into two parts: the principal component part as signal and the rest part as noise, so as to realize the de-noising function of PCA approach, and it is then combined with PPP method to estimate the spectrum width. Due to the good de-noising performance of PCA approach, this new method improves the detection performance of traditional PPP method especially under the condition of low SNR.

With funnel‐tube array, the optical efficiency of the color‐converted micro‐LED display is improved by ~3X, while the crosstalk is eliminated. After optimization of the taper angle, the ambient contrast ratio is also improved due to higher light intensity.

A full‐color micro‐LED display can be achieved by red, green, and blue (RGB) chips or by a blue/ultraviolet (UV) micro‐LED array to pump downconverters. The latter helps relieve the burden of epitaxial growth of tri‐color micro‐LED chips. However, such a color‐converted micro‐LED system usually suffers from color crosstalk and low efficiency due to limited optical density of color converters. With funnel‐tube array and reflective coating on its inner surface, the crosstalk is eliminated, and the optical efficiency can be improved by more than two times. In addition, the ambient contrast ratio is also improved because of higher light intensity. The color gamut of this device is approximately 92% of DCI‐P3 standard. The color crosstalk of color‐converted micro‐LED displays is eliminated by the funnel‐tube array. With reflective coating on its inner side surface, the optical efficiency can be improved by more than two times. In addition, the ambient contrast ratio is also improved because of higher light intensity.

We develop an experimentally validated numerical simulation model to characterize the electro‐optic properties of uniform standing helix (USH) cholesteric liquid crystal displays. Based on the proposed numerical model, the viewing angle properties are analyzed by taking the optical polarization rotation effect into consideration. Furthermore, we propose two compensation schemes to widen the viewing angle of an USH display and achieve contrast ratio >100:1 over 80° viewing cone.

We have identified an often observed yet unresolved intermediate structure in a popular processing with dimethylformamide solutions of lead chloride and methylammonium iodide for perovskite solar cells. With subsecond time-resolved grazing-incidence X-ray scattering and X-ray photoemission spectroscopy, supplemental with ab initio calculation, the resolved intermediate structure (CH3NH3)2PbI2Cl2·CH3NH3I features two-dimensional (2D) perovskite bilayers of zigzagged lead-halide octahedra and sandwiched CH3NH3I layers. Such intermediate structure reveals a hidden correlation between the intermediate phase and the composition of the processing solution. Most importantly, the 2D perovskite lattice of the intermediate phase is largely crystallographically aligned with the [110] planes of the three-dimensional perovskite cubic phase; consequently, with sublimation of Cl ions from the organo-lead octahedral terminal corners in prolonged annealing, the zigzagged octahedral layers of the intermediate phase can merge with the intercalated methylammonium iodide layers for templated growth of perovskite crystals. Regulated by annealing temperature and the activation energies of the intermediate and perovskite, deduced from analysis of temperature-dependent structural kinetics, the intermediate phase is found to selectively mature first and then melt along the layering direction for epitaxial conversion into perovskite crystals. The unveiled epitaxial conversion under growth kinetics controls might be general for solution-processed and intermediate-templated perovskite formation.

A broadband anti-reflection surface with moth-eye structure for sunlight readable flexible displays is demonstrated. The proposed nanostructure exhibits excellent anti-reflection performance (luminous reflectance 0.23%), low haze (0.95%), great flexibility (curve radius <8 mm), high hardness (>3H) and self-cleaning characteristics. A numerical model is developed to simulate and optimize the nanostructure. Excellent agreement between simulation and experiment is obtained.

A reasonably good alignment of a uniform lying helix (ULH) liquid crystal is achieved and its gray-to-gray (GTG) response time investigated. The averaged GTG rise time is 0.35 ms and fall time is 0.53 ms. Such a fast response time helps suppress image blurs and color breakup for field-sequential color displays.

We propose a new electrode configuration, called diamond-shape in-plane switching (DIPS), to lower the operation voltage of polymer-stabilized blue-phase liquid crystal displays (BPLCDs). Using an industrially-proven BPLC mixture, we can obtain 75% peak transmittance at 15 V, while keeping fast response time. Our DIPS structure enables single-TFT per pixel to drive BPLCDs.