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This study reported an original end-to-end dataflow engineering framework for the quality transfer principle to overcome the quality challenges in real-world honey manufacturing. Firstly, 650 pivotal data points of physical and chemical quality attributes from 65 batches of honey intermediates were characterized through multiple sensors, which included rheological properties, acidity, moisture, and sugars. Furthermore, a hypersensitized TAS1R2@AuNPs/SPCE biosensor was developed to identify biological quality attributes of honey, the powerful affinities between honey intermediates and the TAS1R2 receptor were discovered (KD < 1 × 10-8 M), and the abnormal batches of B2, B23 and C23 were diagnosed by TAS1R2@AuNPs/SPCE biosensor and multivariable algorithm. Finally, the end-to-end dataflow containing physical, chemical and biological critical quality attributes was successfully established to interpret the quality transfer principle of honey manufacturing, which revealed that the front-end refining process was relatively unstable and the back-end refining process was a negligible influence on the quality of honey manufacturing. This framework embraces quality management, quality transfer, and biosensor information, which will contribute to discovering the quality transfer principle in industrial innovation for intelligent manufacturing. [ABSTRACT FROM AUTHOR]

Deoxyschizandrin (DS) is a bioactive benzocyclooctadiene lignan found in the fruit of Schisandra chinensis. However, poor bioavailability and non-specificity of DS frequently caused low therapeutic efficacy. In the present study, DS-liposome (DS-lipo) was implemented to enhance the hepatic targeting and inhibition effects on adipocyte differentiation in 3T3-L1 cells. The formulations enabled encapsulation of as much as 24.14% DS. The DS-lipo prepared was about 73.08 nm, as measured by laser light scattering (LLS) morphology. In the visual field of a scanning electron microscope (SEM), the liposomes were spherical with similar size and uniform dispersion. Fluorescence live imaging study exhibited hepatic targeting of liposomes in vivo. Furthermore, High-Content Analysis (HCS) imaging microassay analyses revealed DS-lipo and DS reduced cytoplasmic lipid droplet in 3T3-L1 adipocytes, with the IC50 value of 8.68 µM and 31.08 µM, respectively. The lipid droplet accumulation inhibition rate of 10 µM DS-lipo was above 90%, which was even superior to the effect of 30 µM DS solution. The current findings suggest that DS-lipo was a therapeutic strategy for alleviating lipid-associated diseases and nonalcoholic fatty liver disease (NAFLD). [ABSTRACT FROM AUTHOR]

Friction stir welding (FSW) is well recognized as a very practical technology for joining magnesium alloys. Although, a large amount of progress have been made on the FSW of magnesium alloys, it should be emphasized that many challenges still remain in joining magnesium using FSW. In this article, we briefly review the background of friction stir welding of magnesium alloys, and then focus on the effects of the friction stir welding on the macrostructure, microstructure evolution, texture distribution, and the mechanical properties of the welding joints. The macro-defects in welds and their relationship to the welding parameters such as welding speed, rotation speed, and axial force were also discussed. The review concluded with some suggested methods improvement and future challenges related to FSW of magnesium alloys. The purpose of the present review paper is to fully understand the relationships between the microstructure and the properties, and then establish a global, state-of-the-art FSW of magnesium alloys. [ABSTRACT FROM AUTHOR]

In this paper, a 2D numerical model that is more physically realistic was established to simulate the complete process of Ti/Al explosive welding. Basing on the ANSYS/AUTODYN software package, the smoothed particle hydrodynamics (SPH) and arbitrary Lagrangian-Eulerian (ALE) were used for running this simulation. The numerical model can capture the typical physics in the explosive welding process, including the expansion of explosives, flyer plate bending, the impact of metal plates, jetting, and the wavy interface. The variable physical parameters during the explosive welding process were discussed. Most parts of the jet originated from the aluminum plate. According to the model, the jet velocity reached 7402 m/s. The pressure at the detonation point was too small to make the two plates to bond. The pressure could reach an order of magnitude of 107 kPa when the detonation energy tended to be stable and was far more than the yield strength of both materials, which resulted in an obvious narrow region of plastic strain emerging close to the collision zone. The signs of shear stresses between the two plates were the opposite. The interface morphology changed from straight to wave along the propagation of the detonation wave in the simulation, which was consistent with the experimental results. [ABSTRACT FROM AUTHOR]

The effect of deep cryogenic treatment on the microstructure and corrosion resistance of an AZ61 magnesium alloy metal inert-gas (MIG) welded joint was investigated. The welded joints were deep-cryogenically treated using different parameters, and were analyzed by metallographic observations, X-ray diffraction, microhardness, and NaCl immersion test. The results show that the treatment changes the microstructure of the entire joint by causing grain refinement and increase in the β-phase. The crystal structure, chemical composition, and electrode potentials are different for the α and the β-phases. Therefore, any change in content, status, and distribution of the β phase has important implications on the corrosion resistance of the samples. With an increase in the holding time, the microhardness value of the whole joint increases, and the difference between the three regions of the joint decreases. The results of the NaCl immersion test show that there is an improvement in the corrosion resistance of the treated joints. Compared with the untreated samples, the corrosion potential of the samples treated by deep cryogenic treatment for 4 h at -180 °C is about 0.017 V higher, and the corrosion current density decreased by one order of magnitude (from about 2.769 × 10-5 A․cm-2 to 1.578 × l0-6 A․cm-2). [ABSTRACT FROM AUTHOR]

A bimetal composite of 2205 duplex stainless steel and AZ31B magnesium alloy was cladded successfully through the method of explosive welding. The microstructural characteristics and mechanical properties of 2205/AZ31B bimetal composite are discussed. The interface of 2205/AZ31B bimetallic composite was a less regular wavy morphology with locally melted pockets. Adiabatic shear bands occurred only in the AZ31B side near explosive welding interface. The microstructure observed with EBSD showed a strong refinement near the interface zones. Line scan confirmed that the interface had a short element diffusion zone which would contribute to the metallurgical bonding between 2205 duplex stainless steel and AZ31B magnesium alloy. The value of micro-hardness near the bonding interface of composite plate increased because of work hardening and grain refinement. The tensile shear strength of bonding interface of 2205/AZ31B composite was 105.63 MPa. Tensile strength of 2205/AZ31B composite material was higher than the base AZ31B. There were two abrupt drops in stress in the stress-strain curves of the 2205/AZ31B composite materials. [ABSTRACT FROM AUTHOR]

Objective: A method for rapid analysis of the refining process of honey was developed based on near-infrared (NIR) spectroscopy. Methods: Partial least square calibration models were built for the four components after the selection of the optimal spectral pretreatment method and latent factors. Results: The models covered the samples of different temperatures and time points, therefore the models were robust and universal. Conclusions: These results highlighted that the NIR technology could extract the information of critical process and provide essential process knowledge of the honey refining process. [ABSTRACT FROM AUTHOR]

The electrical and optical properties of the carbon doped GaN grown on Si substrate by metal-organic chemical-vapor deposition are investigated. Carbon impurity doping can improve the breakdown voltage effectively. However excess carbon in contrast depresses the breakdown voltage. This result is correlated with the carbon dopant behaviour in GaN which can be observed by analyzing the photoluminescence (PL) spectra. It is explained that the carbon impurity favours the formation of CN (carbon substitution of nitrogen) which acts as a deep level acceptor. The acceptor compensates the n-type background impurities, which may resulting in suppressing the leakage current at high electric field, and leads to the improvement of the breakdown voltage. However, with excess carbon doping level, a significant amount of CGa (carbon substitution of gallium) form in GaN. The CGa, acting as the donor, compensates the CN and hence impairs the concentration of the deep level acceptor. In a result, the compensation of the n-type background impurities by the deep level acceptor is curbed by the CGa-CN self-compensation effect, which leads to the decrease of the breakdown voltage. [ABSTRACT FROM AUTHOR]

Background: This study aims to analyze the active pharmaceutical ingredients (APIs) of licorice (Radix Glycyrrhizae; gancao), including glycyrrhizic acid, liquiritin, isoliquiritin and total flavonoids, in multi-ingredient and multi-phase extraction by online near-infrared technology with fiber optic probes and chemometric analysis. Methods: High-performance liquid chromatography and ultraviolet spectrophotometry determined the APIs content in different extraction phases by online near-infrared analysis, which included sample set selection by the Kennard--Stone algorithm, optimization of spectral pretreatment methods (i.e., orthogonal signal correction and wavelet denoising spectral correction), and model calibration by the partial least-squares algorithm, moving-window partial least-squares algorithm and synergy interval partial least-squares (SiPLS) algorithm. The relative errors and F values were used to assess the models in different extraction phases. Results: The root-mean-square error of correction, root-mean-square error of cross-validation and root-mean-square error of prediction of APIs in the SiPLS model was less than 0.07. The F values of glycyrrhizic acid, liquiritin, isoliquiritin and total flavonoids were 10,765, 32,431, 649 and 6080, respectively, which were larger than 6.90 (P < 0.01). Conclusion: The study demonstrated the feasibility of online NIR analysis in the multi-ingredient and multi-phase extraction of APIs from licorice. [ABSTRACT FROM AUTHOR]

Al0.4Ga0.6N/Al0.65Ga0.35N heterojunction phototransistors have been fabricated from the epi-structure grown by low-pressure metal organic chemical vapor deposition on c-plane sapphire substrates. P-type conductivity of the AlGaN base layer was realized by using indium surfactant-assisted Mg-delta doping method. Regrowth technique was used to suppress the Mg memory effect on the n-type emitter. The fabricateddevices with a 150-µm-diameter active area exhibited a bandpass spectral response between 235 and 285nm. Dark current was measured to be less than 10pA for bias voltages below 2.0V. A high optical gain of 1.9 × 10³ was obtained at 6V bias. [ABSTRACT FROM AUTHOR]

High hole concentration was achieved in Mg-doped AlxGa1-xN (x~0.4) by using indium-surfactant-assisted delta doping method. A maximum carrier concentration of 4.75 × 1018cm-3 was obtained, which is three times higher than that of the conventionally delta-doped sample. Sheet resistivity as low as 2.46 × 104 Ω/sq was realized, benefiting from the high hole concentration (p). Analysis results show that the Mg incorporation is effectively enhanced, while the compensation ratio and acceptor activation energy (EA) are significantly reduced by using In surfactant. It was also found that the In surfactant may induce stronger valence-band modulation, contributing to the decrease of EA and the increase of p. [ABSTRACT FROM AUTHOR]

Model performance of the partial least squares method (PLS) alone and bagging-PLS was investigated in online near-infrared (NIR) sensor monitoring of pilot-scale extraction process in Fructus aurantii. High-performance liquid chromatography (HPLC) was used as a reference method to identify the active pharmaceutical ingredients: naringin, hesperidin and neohesperidin. Several preprocessing methods and synergy interval partial least squares (SiPLS) and moving window partial least squares (MWPLS) variable selection methods were compared. Single quantification models (PLS) and ensemble methods combined with partial least squares (bagging-PLS) were developed for quantitative analysis of naringin, hesperidin and neohesperidin. SiPLS was compared to SiPLS combined with bagging-PLS. Final results showed the root mean square error of prediction (RMSEP) of bagging-PLS to be lower than that of PLS regression alone. For this reason, an ensemble method of online NIR sensor is here proposed as a means of monitoring the pilot-scale extraction process in Fructus aurantii, which may also constitute a suitable strategy for online NIR monitoring of CHM. [ABSTRACT FROM AUTHOR]

Electrically driven single-pyramid InGaN/GaN micro light-emitting diode (μ-LED) on silicon substrate has been fabricated and investigated. The -LED exhibits a typical p-n diode behavior with a turn-on voltage of 2.5 V and realizes an efficient electroluminescence (EL) under an ultra-small injection current (3μA). An excellent EL pattern with a high-brightness spot at apex, a hexagonal blue ring around the base of pyramid, and six bright spots at the corners of pyramid base was observed. EL wavelength centered at about 450 nm, and a slight peak shift was found as the injection current increased from 100 to 1000 μA. The small magnitude of spectral shift is attributed to the growth of multiple quantum wells on semi-polar GaN pyramid side facets and its accompanied reduction of the quantum-confined Stark effect. The μ-LED has the promising potential for applying in micro display and electrically driven single photon emitter. [ABSTRACT FROM AUTHOR]

Laser-induced breakdown spectroscopy (LIBS) was applied to perform a rapid elemental analysis and provenance study of Blumea balsamifera DC. Principal component analysis (PCA) and partial least squares discriminant analysis (PLS-DA) were implemented to exploit the multivariate nature of the LIBS data. Scores and loadings of computed principal components visually illustrated the differing spectral data. The PLS-DA algorithm showed good classification performance. The PLS-DA model using complete spectra as input variables had similar discrimination performance to using selected spectral lines as input variables. The down-selection of spectral lines was specifically focused on the major elements of B. balsamifera samples. Results indicated that LIBS could be used to rapidly analyze elements and to perform provenance study of B. balsamifera. [ABSTRACT FROM AUTHOR]

Background: Extraction process of dried flowers of formula particles should be investigated from lab investigation to pilot-scale because of good water absorbing capacity and obscure active pharmaceutical ingredients (API) dissolution. Objective: Reliable analysis of on-line near-infrared (NIR) technique and novel application in fascinating modern, traditional Chinese medicine production (formula particles) was proved. Materials and Methods: The extraction process of Sophora japonica L. (formula particles) was used as an example, the rutin was regarded as API. On-line NIR technology was used to monitor the variation of rutin in the extraction process. High-performance liquid chromatography (HPLC) was used as a reference method to determine the content of rutin during the extraction process. The sample set was selected by Kennard-Stone (KS) algorithm. Different pretreatment methods were compared. The synergy interval partial least square (SiPLS) algorithm was applied. Chemometrics indicators and multivariate detection limits method were mutually used to assess the model. Results: According to both errors a (0.05) and ß (0.05), rutin content could be detected by on-line NIR, which was more than 0.181 mg/mL. Conclusions: This work demonstrated the feasibility of NIR for on-line determination of rutin in the pilot-scale extraction process of S. japonica. L. It provided technical support for the NIR application in the extraction process of formula particles. [ABSTRACT FROM AUTHOR]

In this paper, crack-free InGaN/GaN multiple quantum wells (MQWs) light-emitting diodes (LEDs) were transferred from Si (111) substrate onto the electroplating Cu submount, with inserting a 5-pair TiO2/SiO2 omnidirectional reflector (ODR) and an Al mirror, defined as TiO2/SiO2-Al ODR. The reflectivity in the blue spectral range of the TiO2/SiO2-Al ODR was as high as 97%. The current-voltage (I-V) characteristics showed no obvious degradation of electrical properties for the ODR-based LED on Cu. In comparison to conventional LEDs on Si without ODRs, the light output of ODR-based LEDs on Cu was enhanced by 59.3% at a driving current of 350 mA. The improvement is mainly attributed to the following factors: the removal of the opaque Si substrate, the inserting of the high-reflectivity TiO2/SiO2-Al ODR, and the transfer onto the Cu submount with better thermal conductivity. [ABSTRACT FROM AUTHOR]

The co-sensitization of N719 with a cyclic thiourea functionalized organic dye, coded AZ5, for dye-sensitized solar cells (DSSCs) was demonstrated. Due to its intensive absorption in ultraviolet region, AZ5 could compensate the loss of light harvest induced by triiodide, thereby the short-circuit photocurrent density (Jsc) was increased for co-sensitized (N719+AZ5) DSSC. Moreover, the electron recombination and dye aggregation were retarded upon N719 cocktail co-sensitized with AZ5, thus the open-circuit voltage (Voc) of co-sensitized device was enhanced as well. The increased Jsc (17.9 mA ⋅ cm-2) combined with the enhanced Voc (698 mV) ultimately resulted in an improved power conversion efficiency (PCE) of 7.91% for co-sensitized DSSC, which was raised by 8.6% in comparison with that of N719 (PCE = 7.28%) sensitized alone. In addition, co-sensitized DSSC exhibited a better stability than that of N719 sensitized device probably due to the depression of dye desorption. [ABSTRACT FROM AUTHOR]

The growth of InGaN by Ga-migration-enhanced epitaxy using metalorganic chemical vapor deposition is reported. Trench defects, which are usually associated with the generation of basal-plane stacking faults (BSFs), can be significantly diminished by this method. The surface morphology and luminescence characteristics of the deposited InGaN are consequently improved. It is demonstrated that the Ga-migration-enhanced epitaxy can inhibit the generation of BSFs and thus prevent the formation of trench defects in InGaN epilayers. [ABSTRACT FROM AUTHOR]

In this work, we demonstrate an enhanced voltage-blocking ability for GaN-on-Si epitaxial structure with the novel feature of combined Mg-doped-GaN/low-temperature-AlN (LT-AlN) interlayers in the buffer. With an optimized Mg-doping level, such combined interlayers can eliminate the original leakage path at the LT-AlN/GaN interface due to the interfacial roughening effect caused by the Mg doping. As a result, for AlGaN/GaN heterojunction FETs (HFETs) fabricated on such epitaxial structure (template), its off-state leakage current could be reduced by 1–2 orders of magnitude and its breakdown voltage could be remarkably raise to 252%. Although, the Mg-doped-GaN interlayer would cause a little degradation on device on-state performance, such as 6.6% increase of on-resistance, its contribution on improving device’s voltage-blocking ability and reducing its off-state power dissipation outweighs the drawbacks. [ABSTRACT FROM AUTHOR]

Solar-blind avalanche photodiodes were fabricated with an all AlGaN-based epitaxial structure on sapphire by metal–organic chemical vapor deposition. The devices demonstrate a maximum responsivity of 114.1 mA/W at 278 nm and zero bias, corresponding to an external quantum efficiency (EQE) of 52.7%. The EQE improves to 64.8% under a bias of −10 V. Avalanche gain higher than 2 × 104 was obtained at a bias of −140 V. The high performance is attributed to the all AlGaN-based p–i–n structure comprised of undoped and Si-doped n-type Al0.4Ga0.6N on a high quality AlN layer and highly conductive p-type AlGaN grown with In-surfactant-assisted Mg-delta doping. [ABSTRACT FROM AUTHOR]

The influence of different C-doping locations in a GaN/Si structure with a GaN/AlN superlattice (SL) buffer on the material and electrical properties of GaN/Si was studied. The introduction of C doping can remarkably degrade the crystal quality of the buffer. C-doping of a top GaN buffer can introduce compressive stress into the top GaN due to the size effect, while C-doping in a SL buffer can impair the compressive stress provided from the SL buffer to the top GaN. It is found that introducing high-density carbon into the whole buffer can result in a more strain-balanced GaN/Si system with small deterioration of the 2DEG channel. Furthermore, the whole buffer C-doping method is an effective and easy way to achieve a thin buffer with low leakage current and high breakdown voltage (266 V@1 nA mm−1; 698 V@10 μA mm−1; 912 V@1 mA mm−1). By using the whole-buffer C-doping method, a 2.5 μm-thick AlGaN/GaN HFET with a breakdown voltage higher than 900 V was achieved, and the breakdown voltage per unit buffer thickness can reach 181 V μm−1. [ABSTRACT FROM AUTHOR]

A high-performance, electrically driven, single-pyramid, micro light-emitting diode (micro-LED) was demonstrated. An insulated SiO2 layer, which served as a leakage current confinement layer (LCC layer), was deposited at the lower part of the pyramid, before the deposition of the transparent conducting layer. The micro-LED with the LCC layer demonstrated a decrease in reverse leakage current by two orders of magnitude and a 190% increase in light output at 500 µA compared to a micro-LED without an LCC layer. The small leakage current enables the micro-LED to operate with an ultra-low injection current (<1 µA). The improved performance of the micro-LED is attributed to the presence of the LCC layer, which blocks the direct pathway of the leakage current via threading dislocations distributed at the lower part of pyramid and causes carriers to be injected more effectively into the active layers at the nearly defect-free apex of the pyramidal LED. [ABSTRACT FROM AUTHOR]

Both the forward and reverse-bias current transport mechanisms of an AlGaN/GaN Schottky barrier diode with a fully recessed Schottky anode (recessed-SBD) are investigated for the first time. A two-dimensional (2D) device simulation gives insight into the electronic transport. The difference between the forward and reverse conduction paths enables the reduction in Von without sacrificing the low reverse leakage current properties. The results of temperature-dependent current–voltage (T–I–V) measurements show that thermionic field emission (TFE) is the dominant current transport mechanism for forward bias. In the reverse-bias region above the pinch-off voltage, two mechanisms codetermine leakage currents, which contain Frenkel–Poole emission from the overlapped planar contact and tunneling from the recessed sidewall contact. Below the pinch-off voltage, the leakage currents are observed to have exponential temperature dependence, which may be consistent with trap-assisted tunneling (TAT). [ABSTRACT FROM AUTHOR]

The effect of AlN/GaN superlattice (SL) buffer on the strain state in a GaN-on-Si(111) system was studied in detail by room-temperature micro-Raman scattering measurement. An abnormal satellite peak attached to a GaN E2 peak was observed, which was verified to stem from the compressively strained GaN in SLs. The results indicate that the strain-sensitive GaN E2 (high) peak in the GaN-on-Si system with AlN/GaN SLs splits into two peaks because the GaN stress state in the top GaN layer is different from that in SLs. The compressive stress in the GaN layer in SLs was introduced by the AlN layer in each SL period because of the lattice mismatch between GaN and AlN, which ultimately counterbalanced the tensile stress in the top GaN during cooling. Such a counterbalance interaction is strongly dependent on the stiffness coefficient of AlN/GaN SLs, which is proportional to the number of periods of SLs and the relative thickness of AlN in SLs. Such two E2 peaks from GaN enable us to monitor the strain state in the GaN-on-Si system with AlN/GaN SLs quantitatively. [ABSTRACT FROM AUTHOR]