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In this work, we fabricated high-performance GaN-based ultraviolet resonant cavity light-emitting diodes (RCLEDs) with dual dielectric distributed Bragg reflectors (DBRs). The devices were configured a copper plate and AlN current confinement aperture, which improved thermal dissipation and increased the maximum output power density up to 84.03 W/cm2 at injected current density of ~36 kA/cm2. The emission wavelength of the devices is 376.7 nm and narrow cavity modes were observed with a linewidth of 0.24 nm, corresponding to a high quality factor (Q) of 1570.

In this letter, we systematically investigate the impact of randomly distributed ferroelectric/interlayer (FE/IL) and interlayer/oxide-semiconductor (IL/OS) interface traps, both individually and in combination, on the variability of oxide-semiconductor ferroelectric field-effect transistor (OS-FeFET) memory devices. Our study demonstrates that: 1) as the density of IL/OS interface traps ( $\text{N}_{\text {IL/OS}}$ ) increases, the memory window (MW) exhibits significant fluctuation with a larger $\sigma _{\text {MW}}$ , resulting in the degradation of $\mu _{\text {MW}}$ ; 2) MW is impacted by the density of FE/IL interface traps ( $\text{N}_{\text {FE/IL}}$ ) by modifying the electric field in FE and IL layers, consequently leading to a substantial $\mu _{\text {MW}}$ but no obvious change in $\sigma _{\text {MW}}$ ; 3) when considering the combined impact of both types of traps, the impact of FE/IL interface traps on increasing $\mu _{\text {MW}}$ is suppressed with an increased $\text{N}_{\text {IL/OS}}$ . However, it is crucial to note that although the larger $\text{N}_{\text {IL/OS}}$ dominates the overall MW fluctuation, the fluctuation caused by $\text{N}_{\text {FE/IL}}$ cannot be disregarded especially with smaller $\text{N}_{\text {IL/OS}}$ . These findings provide valuable insights into the understanding of interface trap effects on the device variation of OS-FeFET memories.

In this study, the performances of negative capacitance field effect transistors (NCFETs) are compared by simulation using single-domain (SD) and multidomain (MD) models. Based on the MD model with the gradient energy coefficient, the ferroelectric (FE) polarization distribution is investigated. The results reveal the correlation among the FE polarization distribution, the NC effect, and the device performances for different device parameters, including the FE thickness ( ${T}_{\mathrm{FE}}$ ) and the oxide thickness ( ${T}_{\mathrm{OX}}$ ). The FE polarization distribution tends to transform from the SD state into the MD state with the increase of ${T}_{\mathrm{FE}}$ and the decrease of ${T}_{\mathrm{OX}}$ . The increased ${T}_{\mathrm{FE}}$ and decreased ${T}_{\mathrm{OX}}$ could result in a more significant distinction in the FE polarization distribution and a further larger difference in the NC effect between the MD state and the conventional SD state for NCFETs. The phenomenon above is confirmed by transient characteristics in NCFETs. More analysis and design space of NCFETs are provided by the study results.

Continuous-wave green vertical-cavity surface-emitting lasers based on self-formed quantum dots were realized with the lowest threshold current density of 51.97 A cm−2.A short cavity (~4.0 λ, where λ is the wavelength in the media) was adopted to enhance the interaction between spontaneous emission and lasing mode, with a big coupling factor up to 0.094.AlN current confinement layer and the electroplated supporting copper plate were utilized to improve heat dissipation, with a low thermal resistance of 842 K W−1.

The gene KIAA0319 has been reported to be associated with developmental dyslexia (DD) in previous studies, although the results have not always been consistent. However, few studies have been conducted in Uyghur populations. In the present study, we aimed to investigate the association of KIAA0319 polymorphisms and DD in individuals of Uyghurian descent. We used a custom-by-design 48-Plex SNPscan Kit to genotype 18 single-nucleotide polymorphisms (SNPs) of KIAA0319 in a group of 196 children with dyslexia and 196 controls of Uyghur descent aged 8–12 years. As a result, 7 SNPs (Pmin=0.001) of KIAA0319 had nominal significant differences between the cases and controls under specific genotypic models. The two SNPs rs6935076 (P=0.020 under dominant model; P=0.028 under additive model) and rs3756821 (P=0.021 under additive model) remained significantly associated with dyslexia after Bonferroni correction. Linkage disequilibrium analysis showed three blocks within KIAA0319, and only a 10-SNP haplotype in block 3 was present at significantly different frequencies in the dyslexic children and controls. This study indicated that genetic polymorphisms of KIAA0319 are associated with an increased risk of DD in the Uyghur population.

Five organic esters with different curing speeds: propylene carbonate (i.e. high-speed ester A); 1, 4-butyrolactone; glycerol triacetate (i.e. medium-speed ester B); glycerol diacetate; dibasic ester (DBE) (i.e. low-speed ester C), were chosen to react with alkaline phenolic resin to analyze the application conditions of ester cured alkaline phenolic resin. The relationships between the curing performances of the resin (including pH value, gel pH value, gel time of resin solution, heat release rate of the curing reaction and tensile strength of the resin sand) and the amount of added organic ester and curing temperature were investigated. The results indicated the following: (1) The optimal added amount of organic ester should be 25wt.%-30wt.% of alkaline phenolic resin and it must be above 20wt.%-50 wt.% of the organic ester hydrolysis amount. (2) High-speed ester A (propylene carbonate) has a higher curing speed than 1, 4-butyrolactone, and they were both used as high-speed esters. Glycerol diacetate is not a high-speed ester in alkaline phenolic resin although it was used as a high-speed ester in ester cured sodium silicate sand; glycerol diacetate and glycerol triacetate can be used as medium-speed esters in alkaline phenolic resin. (3) High-speed ester A, medium-speed ester B (glycerol triacetate) and low-speed ester C (dibasic ester, i.e., DBE) should be used below 15 ºC, 35 ºC and 50 ºC, respectively. High-speed ester A or lowspeed ester C should not be used alone but mixed with medium-speed ester B to improve the strength of the resin sand. (4) There should be a suitable solid content (generally 45wt.%-65wt.% of resin), alkali content (generally 10wt.%-15wt.% of resin) and viscosity of alkaline phenolic resin (generally 50-300 mPa∙s) in the preparation of alkaline phenolic resin. Finally, the technique conditions of alkaline phenolic resin preparation and the application principles of organic ester were discussed.

We demonstrated vertical-structured InGaN/GaN multiple-quantum-well (MQW) solar cells with enhanced performances at a wavelength of 510 nm. The enhancement was achieved by using a ptype ohmic mirror with a combined indium-tin-oxide film and an aluminum (Al) reflector inserted beneath the MQW absorption region. In addition, both good ohmic contact and high reflection were observed. The vertical-structured MQW solar cell with an Al reflector exhibited significant improvements in device performances as compared to that without the Al reflector, including a 49% increase in the short-circuit current density and a 56% increase in the power conversion efficiency.

Multi-stage hydraulic fracturing of horizontal wells is the main stimulation method in recovering gas from tight shale gas reservoirs, and stage spacing determination is one of the key issues in fracturing design. The initiation and propagation of hydraulic fractures will cause stress redistribution and may activate natural fractures in the reservoir. Due to the limitation of the analytical method in calculation of induced stresses, we propose a numerical method, which incorporates the interaction of hydraulic fractures and the wellbore, and analyzes the stress distribution in the reservoir under different stage spacing. Simulation results indicate the following: (1) The induced stress was overestimated from the analytical method because it did not take into account the interaction between hydraulic fractures and the horizontal wellbore. (2) The hydraulic fracture had a considerable effect on the redistribution of stresses in the direction of the horizontal wellbore in the reservoir. The stress in the direction perpendicular to the horizontal wellbore after hydraulic fracturing had a minor change compared with the original in situ stress. (3) Stress interferences among fractures were greatly connected with the stage spacing and the distance from the wellbore. When the fracture length was 200 m, and the stage spacing was 50 m, the stress redistribution due to stage fracturing may divert the original stress pattern, which might activate natural fractures so as to generate a complex fracture network.

To introduce the experience of professor YIN Ke-jing, a national senior and famous doctor of traditional Chinese medicine, in treatment of abdominal distension after abdominal surgery with warming-needle moxibustion at Gōngsūn (SP 4).

Time-resolved photoluminescence spectra of vertical cavity surface emitting laser (VCSEL) structures under different excitation intensity are investigated. The effect of the distributed Bragg reflectors (DBR) on the laser emission and the mechanism of multi-longitudinal-mode are analysed. A broad peak around 2.80eV is observed from the structure without DBR cavity when pumped under low excitation intensity. At higher excitation density up to 21.4kW/cm2, a lasing peak appears at 2.86eV, and exhibits a rapid growth and red shift with the increase of the excitation density. The decay time of the peak is about 66ps. When the spectrum is measured after the deposition of DBR on the top side of the grown nitride structure, the number of peaks increases to 7, and the free spectral range 0.21×1014 Hz is close to the value that calculated by the Fabry-Perot cavity length. After depositing the second DBR, multi PL peaks around 2.87eV are observed. The relationship of laser emission intensity and angle of the polarizer shows nearly a cosine square variation. However, the polarization characteristics of the four main peaks are different, which indicates that these peaks occurr by the oscillation of different optical cavities.

Blast furnace gas ash is one of the main solid wastes in iron and steel enterprise. The recovery of zinc from gas ash can result in considerable economic and environmental benefits. The effect of NH3/NH4+, L/S, [NH3]T and leaching time on the zinc leaching rate of blast furnace gas ash by using ammonia leaching process had been investigated in this paper. The results show that L/S and NH3/NH4+ are the main influence factors under the experimental condition. The optimal conditions for leaching process are: NH3/NH4+=2:1, L/S=4:1, [NH3]T =5mol/L, and the leaching time is 3 hours. The zinc leaching rate is 82.84% under the optimized conditions. The lead content in leaching solution is high, so the main task is to improve the removal rate of lead in the purification process.

Along with the continuous development of embedded systems, embedded products take higher requirements on the scale and performance of system software, and contributing to the complexity of control algorithm. So it would take more time and expense to realize the control algorithm. Therefore, traditional design is out of date and cant cope with the modern development rhythm well. While the Model-Based Design, is an efficient design method to deal with complex embedded control systems. It provides a common development and test platform for the engineers. In this paper, we take the power windows control system as example; establish the algorithm model with the Simulink/Stateflow. Then we introduce these process of the control system design which is based on the Model-Based Design method, according to the result of the final experiment, we prove the efficiency of this method, providing a reference for the design of other complex control systems.

This study is to evaluate the biocompatibility of HAP/Ti gradient coating by microarc oxidation and biomimetic process. Titanium alloys were activated by microarc oxidation (MAO), and immersed in simulated body fluid to prepare HAP/Ti gradient coating. Scanning electron microscopy (SEM) had been used to investigate the microstructure of the coatings. The biocompatibility of the coatings was evaluated by animal acute and subacute toxicity test, micronucleus test, hemolysis test, and oral mucosa test. The results showed HAP/Ti gradient coating was successfully fabricated on the substrate. The animal experiment showed the coating had not short-term toxicity, oral mucosa irritation, and micronucleus occurrence rate was 3.2 ‰ and hemolysis rate was 2.5%. The HAP/Ti gradient coating made by MAO and biomimetic process showed good bio-security and compatibility, it may be new oral implant materials.

A new gas source n-type dopant, ethylchloride (EtCl), was used for MBE growth of ZnSe and ZnS. Carrier concentrations up to 3.2 × 1018and 3.5 × 1017cm−3were achieved for ZnSe and ZnS, respectively. The use of the gas source dopant is advantageous in maintaining the MBE chamber.

Optically pumped wavelength-tunable vertical-cavity surface-emitting lasers (VCSELs) operating in the ultraviolet A (UVA) spectrum were demonstrated. The VCSELs feature double dielectric distributed brag reflectors and a wedge-shaped cavity fabricated using the substrate transfer technique and laser lift off, resulting in a graded cavity length in one device. A resonant period gain structure is used in the InGaN/GaN multi-quantum well active region to enhance the coupling between the cavity mode field and the active layers. The optical field inside the cavity is modulated by the cavity length; thus, tunable lasing at different wavelengths is realized at different points of a single VCSEL chip. The lasing wavelength extends from 376 to 409 nm, covering most of the UVA band below the band gap of GaN. The threshold pumping power density of the UVA VCSELs at different wavelengths ranges from 383 to 466 kW/cm2, which is among the lowest values for ultraviolet (UV) VCSELs. This study is promising for the development of small-footprint, power-efficient UV light sources.

Passivation effects of nitrogen acceptor in hydrogenated ZnSe are investigated with low-temperature photoluminescence. Nitrogen-doped samples were exposed to a hydrogen plasma produced by an rf plasma cell. The significant PL spectral change indicates that hydrogen neutralizes the activity of nitrogen acceptors in ZnSe. This is the first observation of intentional hydrogen passivation of nitrogen acceptors in ZnSe, which plays an important role in determining the p-type conductivity of ZnSe grown by metalogranic chemical vapor deposition.