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A systematic study has been conducted on a series of InGaN‐based micro‐light‐emitting diode (μLED) array samples which are achieved using the direct epitaxy overgrown approach on patterned templates by metalorganic chemical vapor deposition technique, where the diameters of the μLEDs are 40, 5, and 3.6 μm, respectively. The selective epitaxy approach allows to circumvent the major limitations of conventional fabrication methods of μLEDs which unavoidably introduce dry‐etching‐induced damages. Electrical characterizations are performed on the selective epitaxy overgrown μLEDs as well as conventional μLEDs fabricated using a standard dry‐etching method. For the overgrown μLEDs, the leakage current per μLED is smaller than those of the conventionally mesa‐etched μLEDs. It is worth highlighting that the single 3.6 μm μLED exhibits as low as a leakage current of 14.1 nA at a bias of −5 V. Moreover, in terms of leakage current density, the overgrown μLEDs exhibit much smaller and more consistent leakage than their mesa‐etched counterparts. Operational voltage RC constants also show more favorable to the overgrown devices than the conventionally mesa‐etched μLEDs. [ABSTRACT FROM AUTHOR]

There is a significantly increasing demand on developing a microLED (μLED) based microdisplay which may be the only display system that can meet the requirements for augmented reality/virtual reality systems, helmet mounted displays, and head‐up displays. However, a number of fundamental challenges which cannot be met by any existing technologies need to be overcome before such a microdisplay with satisfied performance becomes possible. In this paper, a different type of integration concept using an epitaxial approach is proposed, aiming to monolithically integrate μLEDs and high electron mobility transistors (HEMTs) on a single chip. This concept can be potentially realized by using a selective epitaxial overgrowth method on a predefined HEMT template featuring microhole masks. Finally, the proposed epitaxial integration concept is translated into a prototype, demonstrating an 8 × 8 microLED microdisplay, where each μLED is electrically driven by an individual HEMT which surrounds its respective μLED via the gate bias of the HEMT. [ABSTRACT FROM AUTHOR]

High‐quality semi‐polar (11‐22) GaN is obtained by means of growth on patterned (113) silicon substrates featured with stripy grooves and extra periodic gaps which are perpendicular to the grooves. Ga melting‐back during the GaN growth at a high temperature is eliminated as a result of special patterning design. On‐axis X‐ray rocking curve measurements show that the linewidth is significantly reduced down to 339 arcsec. Photoluminescence (PL) measurements at 10 K show strong GaN band‐edge emission only, meaning that any basal stacking fault‐related emission is not observed. Furthermore, green InGaN/GaN light‐emitting diodes (LEDs) with an emission wavelength of around 530 nm are achieved on the semi‐polar GaN grown on the patterned Si substrates. Excitation power‐dependent PL measurements do not show a shift in wavelength, meaning a significant reduction in polarization‐induced piezoelectric fields. Electroluminescence (EL) measurements exhibit that the output power of the semi‐polar LED increases linearly with increasing injection current. It is worth highlighting that the overgrowth technology on designed patterned (113) silicon is a potential approach to manufacturing high‐performance semi‐polar GaN emitters on Si substrates in a long wavelength region. [ABSTRACT FROM AUTHOR]

In order to meet the needs of high-precision guidance for intercepting hypersonic targets, a novel head-pursuit guidance law considering the dynamic characteristics of a missile control system and the target mobility is presented via combining a fast power reaching law with backstepping sliding mode control in this paper. Initially, a three-dimensional head-pursuit system model of the missile and target is established. Subsequently, the system model is decomposed into a pitch plane system and lateral plane system, the control system dynamics are equivalent to second-order systems, and finite-time disturbance observers are introduced to estimate the target accelerations. On the basis of the previous work, the head-pursuit guidance laws of the vertical system and the lateral system which can stabilize the closed-loop system are designed separately and strict proofs of the methods are given. Finally, simulations are carried out to verify the effectiveness of this head-pursuit guidance law. [ABSTRACT FROM AUTHOR]

Facet‐dependent on‐surface reactions are systematically studied on zinc‐blende CdSe nanoplatelets with atomically‐flat {001} basal facets and small yet non‐polar side facets. The on‐surface half‐reactions between the surface Se sites and Cd carboxylates in the solution are qualitatively equivalent to those on the spheroidal counterparts. Conversely, the on‐surface half‐reactions between the surface Cd sites and the activated Se precursors in solution show a strong facet‐dependence, which includes three distinguishable stages. In the first stage, the Se precursors adsorb onto the small and non‐polar side facets of the nanoplatelets. The second stage is initiated by the adsorbed Se precursors at the side‐basal plane edges and proceeds from the edges to the center of the basal planes in quasi‐zeroth‐order kinetics. In the third stage, the nanoplatelets are dismantled, which includes the creation of a hole in the middle and a build‐up of thick edges. [ABSTRACT FROM AUTHOR]

The transcription factors CBF1/2/3 are reported to play a dominant role in the cold responsive network of Arabidopsis by directly regulating the expression levels of cold responsive ( COR) genes. In this study, we obtained CRISPR/Cas9-mediated loss-of-function mutants of cbf1∼3. Over 3,000 COR genes identified by RNA-seq analysis showed a slight but significant change in their expression levels in the mutants compared to the wild-type plants after being treated at 4 °C for 12 h. The C-repeat (CRT) motif (5′-CCGAC-3′) was enriched in promoters of genes that were up-regulated by CBF2 and CBF3 but not in promoters of genes up-regulated by CBF1. These data suggest that CBF2 and CBF3 play a more important role in directing the cold response by regulating different sets of downstream COR genes. More than 2/3 of COR genes were co-regulated by two or three CBFs and were involved mainly in cellular signal transduction and metabolic processes; less than 1/3 of the genes were regulated by one CBF, and those genes up-regulated were enriched in cold-related abiotic stress responses. Our results indicate that CBFs play an important role in the trade-off between cold tolerance and plant growth through the precise regulation of COR genes in the complicated transcriptional network. [ABSTRACT FROM AUTHOR]

A high-silica zeolite with a TON structure designated as ZJM-4 was successfully synthesized in the absence of any organic templates and zeolite seeds. Many factors such as the SiO2/K2O ratio, Si/Al ratio, SiO2/H2O in the starting aluminosilicate gels, crystallization temperature, and crystallization time strongly influence the formation of the ZJM-4 zeolite. Interestingly, this synthesis shows very efficient silica utilization in the starting gels (>80 %). Catalytic tests on the isomerization of m-xylene to p-xylene show that the ZJM-4 catalyst has high selectivity to p-xylene (ca. 80 %), which could be potentially important for industrial applications for the ZJM-4 zeolite as a candidate catalyst in the future. [ABSTRACT FROM AUTHOR]

Highlights from the article: From Nanofibers to Nanorods: Nanostructure of Peptide-Drug Conjugates Regulated by Polypeptide-PEG Derivative and Enhanced Antitumor Effect The initially published version of this article contained a typographical error in the affiliation linked with the author Gang Cao (Zhengjiang Chinese Medical University). The authors apologize for any inconvenience or misunderstanding that this error may have caused.