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A set of colour tuning K2Ba(MoO4)2: Dy3+/Eu3+ (KBM: Dy3+/Eu3+) phosphors were fabricated by solid-state method. The phase purity of as-prepared materials was validated by XRD and DRS analyses. The KBM: 0.03Dy3+ sample exhibits two major luminescence lines at 481 and 572 nm when excited by 351 nm light, corresponding to Dy3+ ions' typical transitions of 4F9/2 → 6HJ (J = 15/2, 13/2). By introducing Eu3+ ions into KBM: 0.03Dy3+ phosphor, the ET from Dy3+ to Eu3+ ions arises, leading to colour tuning from green via yellowish green to pink with changing Eu3+ ions' concentration, along with the lowest CCT of KBM: 0.03Dy3+/0.03Eu3+ sample. It can be verified by PLE and PL spectra analysis combined with the decay times of KBM: 0.03Dy3+/yEu3+ samples. The energy transfer mechanism is also expounded. Meanwhile, the emission intensities at 423 K still maintain 72.8% for Dy3+ ions and 91.2% for Eu3+ ions relative to 303 K of the KBM: 0.03Dy3+/0.03Eu3+ sample, displaying its brilliant thermal stability. All these results connote that KBM: Dy3+/Eu3+ phosphors are prospected to be used for the near-UV excited white light-emitting diodes. [ABSTRACT FROM AUTHOR]

(+)- and (-)-Tedanine [(+)-1 and (-)-1], a pair of new enantiomeric indolone alkaloids, along with nine compounds (2–10) were isolated from the marine sponge Tedania sp. The structures of (+)-1 and (-)-1 including absolute configurations were determined by spectroscopic analysis and quantum chemical calculation. Compounds (+)-1 and (-)-1 were the first examples of indolone alkaloids isolated from this genus. In addition, the cytotoxic and antibacterial activities of these compounds were also evaluated. [ABSTRACT FROM AUTHOR]

Two new alkaloids, spongimides A (1) and B (2), along with five known ones (3–7), were isolated from the marine sponge Spongia sp. The structures of 1 and 2 were determined by the spectroscopic methods (UV, IR, MS, and NMR) and X-ray diffraction analysis. Compounds 1, 3, and 4 were the first examples of 2,4-imidazolidinediones isolated from this genus. In addition, the cytotoxic and antibacterial activities of compounds 1 and 2 were also evaluated. [ABSTRACT FROM AUTHOR]

Single-layer SrTiO 3 film and SiO 2 /SrTiO 3 composite film electroluminescence (EL) devices were fabricated on n-Si substrate though vacuum electron vapor deposition (EBVD) technique. The film layers in the device were analyzed using various detection methods to determine their microstructure and composition, and the EL properties of both types of devices were compared. EL experimental results show that both devices can emit white light visible to the naked eye when the forward bias is applied. Moreover luminescence intensity of SiO 2 /SrTiO 3 composite thin film devices is much higher than that of single-layer SrTiO 3 thin film devices. The EL spectrum analysis of the device samples shows that there are three luminescence peaks in both types of devices, and they are located in the blue, yellow and red regions. Three emission peaks of single-layer SrTiO 3 thin film devices are located at 460 nm (blue region), 580 nm (yellow region) and 685 nm (red region). Three luminescence peaks of SiO 2 /SrTiO 3 composite thin film devices are located at 460 nm (blue region), 585 nm (yellow region) and 716 nm (red region). In composite film devices, SiO 2 acts as an electron barrier layer, confining electrons to the SrTiO 3 film layer and increasing the chance for the electrons in the SrTiO 3 conduction band to participate in the composite luminescence. As a result, the blue peak emission intensity of the SrTiO 3 composite film device is significantly enhanced, while the overall white light emission intensity of the composite thin film device is greatly improved. Additionally, the color coordinates of SiO 2 /SrTiO 3 composite film device is closer to those of standard white light according to CIE standards. • The electroluminescence properties of single layer SrTiO 3 film and SiO 2 /SrTiO 3 composite film are prepared and compared. • composite film device not only effectively improves the luminance, but also has CIE color coordinates closer to standard white light.The SiO 2 /SrTiO 3 composite film device has higher brightness and CIE coordinates are closer to standard white light. • This study provides a way to develop white perovskite light-emitting diodes with small volume, low cost and no phosphor. [ABSTRACT FROM AUTHOR]

A novel valerenane sesquiterpenoid sinulaspirolactam A (1), together with five known compounds, was isolated from the soft coral Sinularia sp. Their structures were determined by spectroscopic analyses. The absolute configuration of 1 was established by ECD calculation. Compound 1 was the first example of valerenane sesquiterpenoid bearing an aza-spiro[4.5] ring moiety, the plausible biogenetic pathway of which was proposed. Cytotoxic activities of these compounds were also evaluated. [ABSTRACT FROM AUTHOR]

Two new flavonoids, bismilachinone ( 11 ) and smilachinin ( 14 ), were isolated from the leaves of Smilax china L. together with 14 known compounds. Their structures were elucidated using spectroscopic methods. The PTP1B, α-glucosidase, and DPP-IV inhibitory activities of compounds 1 – 16 were evaluated at the molecular level. Among them, compounds 4 , 7 , and 10 showed moderate DPP-IV inhibitory activities with IC 50 values of 20.81, 33.12, and 32.93 μM, respectively. Compounds 3 , 4 , 6 , 11 , 12 , and 16 showed strong PTP1B inhibitory activities, with respective IC 50 values of 7.62, 10.80, 0.92, 2.68, 9.77, and 24.17 μM compared with the IC 50 value for the positive control (ursolic acid: IC 50 = 1.21 μM). Compounds 2 – 7 , 11 , 12 , 15 , and 16 showed potent α -glucosidase inhibitory activities, with respective IC 50 values of 8.70, 81.66, 35.11, 35.92, 7.99, 26.28, 11.28, 62.68, 44.32, and 70.12 μM. The positive control, acarbose, displayed an IC 50 value of 175.84 μM. In the kinetic study for the PTP1B enzyme, compounds 6 , 11 , and 12 displayed competitive inhibition with K i values of 3.20, 8.56, and 5.86 μM, respectively. Compounds 3 , 4 , and 16 showed noncompetitive inhibition with K i values of 18.75, 5.95, and 22.86 μM, respectively. Molecular docking study for the competitive inhibitors ( 6 , 11 , and 12 ) radically corroborates the binding affinities and inhibition of PTP1B enzymes. These results indicated that the leaves of Smilax china L. may contain compounds with anti-diabetic activity. [ABSTRACT FROM AUTHOR]

The phytochemical investigation on the fruits of Flueggea virosa resulted in the discovery of two new norsecurinine-derived alkaloid dimers, norsecurinamines A and B ( 1 and 2 ). Compound 1 is the first hetero-dimeric alkaloid possessing norsecurinine and donaxaridine units, and 2 represents the first example of NH -linked dimeric Securinega alkaloid. Their structures and absolute configuration were elucidated on the basis of extensive spectroscopic analysis as well as single-crystal X-ray diffraction method. A plausible biogenetic pathway of 1 was also proposed. [ABSTRACT FROM AUTHOR]

Five undescribed eremophilane-type sesquiterpenes, remophilanetriols E -I (1 – 5), along with seven known compounds (6 – 12) were isolated from the fresh roots of Rehmannia glutinosa. Their structures were characterized by extensive spectroscopic data analysis and their absolute configurations were determined by comparing their calculated electronic circular dichroism (ECD) spectra and experimental ECD spectra. The anti-pulmonary fibrosis activities of all compounds were evaluated in vitro by MTT methods, and compounds 2 , 8 , 10 , and 12 exhibited excellent anti-pulmonary fibrosis activities. In addition, compound 2 can reduce the levels of ROS and apoptosis in TGF-β1-induced BEAS-2B cells. [Display omitted] [ABSTRACT FROM AUTHOR]

Inhibitors of protein tyrosine phosphatase 1B (PTP1B) are promising agents for the treatment of type 2 diabetes and obesity. The bioactivity-guided isolation led to the separation of two new compounds, (±)-tradescantin ( 13 ) and tradescantoside ( 16 ), along with fourteen known compounds ( 1 – 12 , 14 , and 15 ) from the aerial parts of Tradescantia spathacea Sw. (Commelinaceae). Their chemical structures were elucidated by spectroscopic methods as well as by comparing with those reported in the literature. The isolated compounds ( 1 – 16 ) were then examined for their inhibitory activity toward PTP1B. The results indicated that compounds 2 , 6 , 8 , and 12 possessed potent inhibition with IC 50 values of 7.82 ± 0.79, 6.80 ± 0.89, 4.55 ± 0.92, and 6.38 ± 0.14 μM, respectively. Kinetic study of compounds 2 , 6 , 8 , 12 , 13 , and 16 was conducted and the structure–activity relationships of the isolated compounds ( 1 – 16 ) were also discussed herein. To the best of our knowledge, all the isolates were separated for the first time from this plant. [ABSTRACT FROM AUTHOR]

Glyphosate is one of the most commonly-used and non-selective herbicides in agriculture, which may directly pollute the environment and threaten human health. A simple and effective approach to assessment of its damage to the natural environment is thus quite necessary. However, traditional chromatography-based detection methods usually suffer from complex pretreatment procedures. Herein, we propose a simple and sensitive method for the determination of glyphosate by combining ninhydrin reaction and surface-enhanced Raman scattering (SERS) spectroscopy. The product (purple color dye, PD) of the ninhydrin reaction is found to SERS-active and directly correlate with the glyphosate concentration. The limit of detection of the proposed method for glyphosate is as low as 1.43 × 10 − 8 mol·L − 1 with a relatively wider linear concentration range (1.0 × 10 − 7 -1.0 × 10 − 4 mol·L − 1 ), which demonstrates its great potential in rapid, highly sensitive concentration determination of glyphosate in practical applications for safety assessment of food and environment. [ABSTRACT FROM AUTHOR]

Astract Two new C 18 -diterpenoid alkaloids, sinomontadine ( 1 ) and sinomontanine N ( 2 ), were isolated from Aconitum sinomontanum . Their structures were determined by spectroscopic methods and X-ray crystallographic analysis. Sinomontadine ( 1 ) features an unprecedented skeleton containing a seven-membered ring (A-ring), while sinomontanine N ( 2 ) is chlorinated. A plausible biogenetic pathway for 1 was proposed. [ABSTRACT FROM AUTHOR]