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Experimental and statistical analyses of geometry characteristics of Inconel 718 laser clad layer with response surface methodology
摘要： Hierarchical nanozeolites are highly desired for heavy oil conversion because of their fast mass transfer, good site accessibility, and short diffusion length compared with their conventional counterparts. Here, we provide a facile amino acid-assisted strategy to synthesize hierarchical ZSM-5 (MFI) zeolite nanocrystals by two-step crystallization in a concentrated gel system. Strikingly, each virus-like zeolite nanoparticle with abundant interconnected intracrystalline mesopores is a high-quality single crystal that is defect-free as confirmed by electron diffraction and NMR analysis. By utilizing advanced electron microscopy techniques, we have studied the evolution process of single-crystalline hierarchical ZSM-5 nanocrystals that involves oriented aggregation of protozeolitic nanoparticles formed at low temperature followed by intraparticle ripening at high temperature. The as-prepared hierarchical Ni@ZSM-5 catalysts exhibit superior catalytic performance in hydrodeoxygenation of stearic acid and palm oil.
关键词： intraparticle ripening,hierarchical nanozeolites,interconnected mesopores,defect-free,single-crystalline,amino acid-assisted strategy,hydrodeoxygenation,oriented aggregation,ZSM-5
更新于2025-09-11 14:15:04
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Successful Treatment of Adult-Onset Recurrent Respiratory Papillomatosis with CO <sub/>2</sub> Laser and Photodynamic Therapy
摘要： Recurrent respiratory papillomatosis is a noninvasive benign epithelial tumor caused by human papillomavirus. Clinically, it featured rapid growth, multifocus, and frequent recurrence. Though a number of therapies have been investigated, the recurrence after treatment is always a challenge. In this report, we describe a 27-year-old male patient with recurrent respiratory papillomatosis who was treated with CO2 laser therapy followed by 5-aminolevulinic acid photodynamic therapy (ALA-PDT). There was no adverse reaction after treatment and no recurrence during the follow-up time.
关键词： CO2 laser therapy,5-aminolevulinic acid,human papillomavirus,photodynamic therapy,Recurrent respiratory papillomatosis
更新于2025-09-11 14:15:04
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Enhancement of Open‐Circuit Voltage of Perovskite Solar Cells by Interfacial Modification with <i>p</i> ‐Aminobenzoic Acid
摘要： Various approaches of interface engineering are shown to be effective in improving the device performance of organic–inorganic hybrid perovskite solar cells (PSCs). The modification of the photoactive layer of PSC, CH3NH3PbI3 (MAPbI3), by spin-coating a layer of p-aminobenzoic acid (PABA), which can significantly enhance the open-circuit voltage (VOC), the fill factor (FF), and the power conversion efficiency (PCE) of PSCs, is herein reported. The champion device shows a short-circuit current ( JSC) of 22.83 mA cm?2, VOC of 1.167 V, FF of 0.768, and PCE of 20.47%. The improvement in photovoltaic performance is attributed to the suppression of carrier trap states and the improvement in the morphologies of perovskite films. This work demonstrates a simple and effective protocol to enhance the device performance, and provides an insight into the influence of PABA post-treatment on the charge carrier dynamics.
关键词： carrier dynamics,interface engineering,p-aminobenzoic acid,postdeposition treatment,organic–inorganic hybrid perovskite
更新于2025-09-11 14:15:04
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Time controlled growth of CdSe QDs for applications in white light emitting diodes
摘要： Semiconductor nanophosphors have the exceptional resources to demonstrate the quantum phenomenon due to their tailored-size dependent photoluminescence (PL). The work here is focused on the synthesis of highly luminescent Cadmium Selenide (CdSe) Quantum Dots (QDs) by a simple technique. This is a time dependent process where change in the size of CdSe QDs was observed at a reaction temperature of 100 °C without any inert atmosphere. The CdSe QDs were synthesised by using 3-Mercapto propionic acid (MPA) rather than using the typically utilized capping agent. All the samples were characterised for their optical properties. The size of QDs was calculated in a range up to 3 nm by UV–Vis Spectroscopy and con?rmed by High Resolution Transmission Electron Microscopy (HRTEM). It was clear from the UV studies that QDs exhibit size dependent tunable optical absorption. The broad Photoluminescence (PL) emission spectra depicts the presence of surface defects produced along with band edge spectrum. The absorbance and emission spectra were shifted to the red region due to the quantum con?nement e?ect occurred in QDs. The water soluble QDs were economical and easy to fabricate has applications in Light Emitting Diodes (LEDs).
关键词： 3-Mercapto propionic acid,Light Emitting Diodes,Quantum con?nement,Photoluminescence,CdSe Quantum Dots
更新于2025-09-11 14:15:04
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Frequency Calibration and Stabilization of the Cooling Laser of Ytterbium Lattice Clock with Molecular Iodine Spectroscopy
摘要： Glycyrrhetinic acid (GA), the main bioactive substances of glycyrrhiza uralensis Fisch, has been reported to exhibit hepatoprotective and anti-inflammatory properties. However, the effects and underlying mechanisms of GA in liver ischemia/reperfusion (I/R) injury remain elusive. In this study, mice were pretreated with GA (100 mg/kg) three times a day by gavage prior to I/R injury, and then hepatic histopathological damages, biochemical parameters and inflammatory molecules were evaluated. We found that mice performed with liver I/R showed a significantly increase in plasma aminotransferase (ALT), aspartate aminotransferase (AST), liver cell apoptosis and infiltration of neutrophils compared with the control group. GA pretreatment notably improved liver function, histopathology of liver tissues, and lowered liver cell apoptosis and infiltration of neutrophils. Besides, further analysis indicated that GA pretreatment reduced I/R-induced expression of extracellular HMGB1, inhibited activation of TLR4 and following phosphorylation of IRAK1, ERK, P38 and NF-κB, and attenuated TNF-α and IL-1β production. These data suggested that GA protected against liver I/R injury through a HMGB1-TLR4 signaling pathway and it might be a promising drug for future clinical use in liver transplantation.
关键词： Glycyrrhetinic acid,Inflammation,TLR4,Apoptosis,HMGB1,Liver ischemia/reperfusion injury
更新于2025-09-11 14:15:04
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Synthesis and characterization of 64Cu- and Cy5.5-labeled tetraiodothyroacetic acid derivatives for tumor angiogenesis imaging
摘要： It was previously reported that tetraiodothyroacetic acid (tetrac) inhibits angiogenesis by binding to the cell surface receptor for thyroid hormone on integrin αVβ3. Therefore, we synthesized and evaluated two 64Cu-labeled tetrac derivatives and a Cy5.5-labeled tetrac derivative for tumor angiogenesis imaging. Tetrac was structurally modified to conjugate with 1,4,7,10-tetraazacyclododecane-N,N′,N″,N″′-tetraacetic acid (DOTA) via its hydroxy or carboxylic acid end, and the resulting DOTA-conjugated tetrac derivatives were then labeled with 64Cu. Tetrac was also conjugated with Cy5.5 via its carboxylic acid end. All three tetrac derivatives (1–3) exhibited greater inhibitory activity than tetrac against endothelial cell tube formation. The U87MG cell binding of [64Cu]2 showed a time-dependent increase over 24 h and it was inhibited by 38% at 4 h in the presence of tetrac, indicating specificity of [64Cu]2 to the thyroid hormone receptor site on integrin αVβ3. Positron emission tomography (PET) images of U87MG tumor-bearing mice injected with [64Cu]1 and [64Cu]2 revealed that high radioactivity accumulated in the tumors, and that the tumor uptake and tumor-to-nontarget uptake ratio were higher in small tumors than in large tumors. In addition, the Cy5.5-labeled tetrac derivative (3) displayed a strong near-infrared (NIR) signal in the tumors. Taken together, these results suggest that these ligands hold promise as imaging agents for visualization of tumor angiogenesis.
关键词： Near-infrared imaging,Integrin αVβ3,Angiogenesis,Positron emission tomography,Tetraiodothyroacetic acid
更新于2025-09-11 14:15:04
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Bio-proton coupled semiconductor/metal-complex hybrid photoelectrocatalytic interface for efficient CO <sub/>2</sub> reduction
摘要： Aimed at high-efficiency biomimetic CO2 photoelectrochemical conversion, a bio-proton coupling metal-complex/semiconductor hybrid photoelectrocatalytic interface (Ru-BNAH/TiO2/Cu2O) was constructed by covalently modifying an in situ proton-transfer functionized molecular catalyst (Ru-BNAH) on the surface of a TiO2/Cu2O composite semiconductor substrate electrode. Due to the excellent proton coupling of the bio-proton carrier, the light current density in a CO2 atmosphere of the prepared Ru-BNAH/TiO2/Cu2O photoelectrocatalytic interface was twice as high as that without a proton carrier under the same conditions. Simultaneously, based on the excellent photosensitivity of the metal oxide substrate, the photogenerated electrons could rapidly transfer to the molecular catalyst for efficient CO2 reduction in a water medium. After 8 h irradiation at ?0.9 V potential, the Ru-BNAH/TiO2/Cu2O photoelectrocatalytic interface produced 409.5 μmol formic acid, which was 2.44 times more than that without a proton transfer carrier. In addition, the in situ UV-visible absorption spectra and in situ Raman spectra indicated that the proton transport carrier supplied protons during CO2 reduction. Moreover, the generation of HCOO? in CO2-saturated D2O medium confirmed the proton (H) originated from the proton transfer carrier rather than the solvent (D2O).
关键词： CO2 reduction,formic acid,bio-proton coupling,Ru-BNAH/TiO2/Cu2O,photoelectrocatalytic interface
更新于2025-09-11 14:15:04
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Nutrient Levels in Brassicaceae Microgreens Increase Under Tailored Light-Emitting Diode Spectra
摘要： To increase the nutritional value and levels of essential minerals in vegetable food, microgreens are promising targets. The metabolic processes of microgreens can be managed with different cultivation techniques, which include manipulating the properties of light derived by light-emitting diodes (LEDs). In this study Brassicaceae microgreens (kohlrabi Brassica oleracea var. gongylodes, broccoli Brassica oleracea, and mizuna Brassica rapa var. Japonica) were cultivated under different light spectral quality, and the metabolic changes insoluble sugars (hexoses and sucrose), ascorbic acid, β-carotene, and contents of non-heme iron (Fe) and its connection with magnesium (Mg) or calcium (Ca) levels were monitored. Plants grew under the primary LED light spectrum (the combination of blue light at 447 nm, red at 638 and 665 nm, and far-red at 731 nm) or supplemented with LED green light at 520 nm, yellow at 595 nm, or orange at 622 nm. The photoperiod was 16 h, and a total PPFD of 300 μmol m-2 s-1 was maintained. Under supplemental yellow light at 595 nm, the content of soluble carbohydrates increased significantly in mizuna and broccoli. Under all supplemental light components, β-carotene accumulated in mizuna, and ascorbic acid accumulated significantly in kohlrabi. Under supplemental orange light at 622 nm, Fe, Mg, and Ca contents increased significantly in all microgreens. The accumulation of Fe was highly dependent on promoters and inhibitors of Fe absorption, as demonstrated by the very strong positive correlations between Fe and Ca and between Fe and Mg in kohlrabi and broccoli, and the strong negative correlations between Fe and β-carotene and between Fe and soluble carbohydrates in kohlrabi. Thus, the metabolic changes that occurred in treated microgreens led to increases in the contents of essential nutrients. Therefore, selected supplemental LED wavelengths can be used in the cultivation of Brassicaceae microgreens to preserve and increase the contents of specific nutritionally valuable metabolites.
关键词： microgreens,Brassicaceae,carbohydrates,β-carotene,ascorbic acid,mineral elements,light-emitting diodes
更新于2025-09-11 14:15:04
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Preparation and Characterization of Water-soluble ZnSe: Fe/ZnSe Quantum Dots
摘要： A chiral phosphoric acid-catalyzed kinetic resolution and desymmetrization of para-quinols operating via oxa-Michael addition was developed and subsequently subjected to mechanistic study. Good to excellent s-factors/enantioselectivities were obtained over a broad range of substrates. Kinetic studies were performed, and DFT studies favor a hydrogen bonding activation mode. The mechanistic studies provide insights to previously reported chiral anion phase transfer reactions involving chiral phosphate catalysts in combination with boronic acids.
关键词： directed reactivity,oxa-Michael addition,kinetics,asymmetric catalysis,chiral phosphoric acid,reaction mechanisms
更新于2025-09-11 14:15:04
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[IEEE 2018 IEEE Asia-Pacific Conference on Antennas and Propagation (APCAP) - Auckland (2018.8.5-2018.8.8)] 2018 IEEE Asia-Pacific Conference on Antennas and Propagation (APCAP) - A Novel Directional Multilevel Method Using Waveguide Eigenmode Expansion
摘要： increased, both body weight gain (BWG) and gain:feed increased linearly and quadratically (P < 0.05). The SID lysine requirements for BWG and gain:feed were 1.06% and 1.08% for the one-slope broken-line, 1.17% and 1.22% for the quadratic broken-line, 1.11% and 1.16% for 95% of the upper asymptote of the quadratic model, and 1.12% and 1.17% for the first intercept between the plateau of the one-slope broken-line and quadratic models, respectively. In conclusion, the SID lysine requirements of Ross 308 broilers at the age of 10 to 21 days ranged from 1.06% to 1.17% for BWG and from 1.08% to 1.22% for gain:feed.
关键词： Requirement,Broiler,Standardized ileal digestibility,Lysine,Amino acid
更新于2025-09-11 14:15:04