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1.
Micromachines (Basel) ; 15(8)2024 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-39203592

RESUMO

Highly sensitive infrared photodetectors are needed in numerous sensing and imaging applications. In this paper, we report on extended short-wave infrared (e-SWIR) avalanche photodiodes (APDs) capable of operating at room temperature (RT). To extend the detection wavelength, the e-SWIR APD utilizes a higher indium (In) composition, specifically In0.3Ga0.7As0.25Sb0.75/GaSb heterostructures. The detection cut-off wavelength is successfully extended to 2.6 µm at RT, as verified by the Fourier Transform Infrared Spectrometer (FTIR) detection spectrum measurement at RT. The In0.3Ga0.7As0.25Sb0.75/GaSb heterostructures are lattice-matched to GaSb substrates, ensuring high material quality. The noise current at RT is analyzed and found to be the shot noise-limited at RT. The e-SWIR APD achieves a high multiplication gain of M~190 at a low bias of Vbias=- 2.5 V under illumination of a distributed feedback laser (DFB) with an emission wavelength of 2.3 µm. A high photoresponsivity of R>140 A/W is also achieved at the low bias of Vbias=-2.5 V. This type of highly sensitive e-SWIR APD, with a high internal gain capable of RT operation, provides enabling technology for e-SWIR sensing and imaging while significantly reducing size, weight, and power consumption (SWaP).

2.
Proc Natl Acad Sci U S A ; 121(15): e2319525121, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38564637

RESUMO

The fine regulation of catalysts by the atomic-level removal of inactive atoms can promote the active site exposure for performance enhancement, whereas suffering from the difficulty in controllably removing atoms using current micro/nano-scale material fabrication technologies. Here, we developed a surface atom knockout method to promote the active site exposure in an alloy catalyst. Taking Cu3Pd alloy as an example, it refers to assemble a battery using Cu3Pd and Zn as cathode and anode, the charge process of which proceeds at about 1.1 V, equal to the theoretical potential difference between Cu2+/Cu and Zn2+/Zn, suggesting the electricity-driven dissolution of Cu atoms. The precise knockout of Cu atoms is confirmed by the linear relationship between the amount of the removed Cu atoms and the battery cumulative specific capacity, which is attributed to the inherent atom-electron-capacity correspondence. We observed the surface atom knockout process at different stages and studied the evolution of the chemical environment. The alloy catalyst achieves a higher current density for oxygen reduction reaction compared to the original alloy and Pt/C. This work provides an atomic fabrication method for material synthesis and regulation toward the wide applications in catalysis, energy, and others.

3.
J Phys Condens Matter ; 36(20)2024 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-38324913

RESUMO

A self-consistent quantum-kinetic model is developed for studying strong-field nonlinear electron transport interacting with force-driven phonons within a nanowire system. For this model, phonons can be dragged into motion through strong electron-phonon scattering by fast-moving electrons along the opposite direction of the DC electric field. Meanwhile, the DC-field induced charge current of electrons can be either enhanced or reduced by the same electron-phonon scattering, depending on the relative direction of a DC field with respect to that of an applied temperature gradient for driving phonons. By making use of this quantum-kinetic model beyond the relaxation-time approximation, neither electron nor phonon temperature is required for describing ultrafast electron-phonon scattering and their correlated transports in this 1D electronic-lattice system.

4.
Small ; 20(26): e2311205, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38267814

RESUMO

Urea, as one of the most sustainable organic solutes, denies the high salt consumption in commercial electrolytes with its peculiar solubility in water. The bi-mixture of urea-H2O shows the eutectic feature for increased attention in aqueous Zn-ion electrochemical energy storage (AZEES) technologies. While the state-of-the-art aqueous electrolyte recipes are still pursuing the high-concentrated salt dosage with limited urea adoption and single-anion selection category. Here, a dual-anion urea-based (DAU) electrolyte composed of dual-Zn salts and urea-H2O-induced solutions is reported, contributing to a stable electric double-layer construction and in situ organic/inorganic SEI formation. The optimized ZT2S0.5-20U electrolytes show a high initial Coulombic efficiency of 93.2% and durable Zn-ion storage ≈4000 h regarding Zn//Cu and Zn//Zn stripping/plating procedures. The assembled Zn//activated carbon full cells maintain ≈100% capacitance over 50 000 cycles at 4 A g-1 in coin cell and ≈98% capacitance over 20 000 cycles at 1 A g-1 in pouch cell setups. A 12 × 12 cm2 pouch cell assembly illustrates the practicality of AZEES devices by designing the cheap, antifreezing, and nonflammable DAU electrolyte system coupling proton donor-acceptor molecule and multi-anion selection criteria, exterminating the critical technical barriers in commercialization.

5.
iScience ; 26(12): 108470, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-38077143

RESUMO

Sodium-ion batteries (SIBs) with abundant resource and high safety are attracting intensive interest from both research and industry communities in meeting the ever-increasing energy demands. Despite the rapid advance of SIBs, it is difficult yet necessary to enhance the cycling and rate performance at anode due to the sluggish kinetics of "fat" Na+. This review provides an overview of two-dimensional (2D) nanomaterials with a short ion diffusion pathway and a superior active sites exposure from the perspectives of synthesis, material chemistry, and structure engineering. We present the design principle of ideal carbon materials in SIBs. Moreover, we discuss the structure and chemistry regulations of different 2D materials to promote the efficient ion mass transfer and storage according to the different mechanisms of alloying, conversion, and insertion. Finally, we propose the remaining challenges and the possible solutions, in hope of guiding the future development of this booming field.

6.
ACS Nano ; 17(23): 24012-24021, 2023 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-38019270

RESUMO

Sodium-ion batteries (SIBs) are attracting worldwide attention due to their multiple merits including abundant reserve and safety. However, industrialization is challenged by the scarcity of high-performance carbon anodes with high specific capacities. Here, we report the metal-assisted microcrystalline structure regulation of carbon materials to achieve high-capacity sodium storage. Systematic investigations of in situ thermal-treatment X-ray diffraction and multiple spectroscopies uncover the regulation mechanism of constructing steric hindrance (C-O-C bonds) to restrain the aromatic polycondensation reaction. The carbon precursor of polycyclic aromatic hydrocarbon-type pitch contributes to a high carbon yield rate (40%) compared with those of resin and biomass precursors. The as-synthesized carbon materials deliver high capacities of up to 390 mAh g-1, surpassing many reported carbon anodes for SIBs. Through correlating specific capacity with ID/IG values in Raman spectra and theoretical calculation of carbon materials regulated by different metal elements (Mn, Nb, Ce, Cr, and V), we identify and propose the binding energy as the descriptor for characterizing the capability of regulating the carbon microcrystalline structure to promote sodium storage. This work provides a universal method for regulating the carbon structure, which may lead to the controlled design and fabrication of carbon materials for energy storage and conversion and beyond.

7.
Fitoterapia ; 170: 105662, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37648028

RESUMO

Two new terrein derivatives asperterreinones A-B (1-2), one new octahydrocoumarin derivative (±)-asperterreinin A (6), along with seventeen known compounds, were isolated from Aspergillus terreus F6-3, a marine fungus associated with Johnius belengerii. The structures of 1, 2, and 6 were established on the basis of 1D and 2D NMR, mass spectroscopy, comparative electronic circular dichroism (ECD) spectra analysis, density functional theory calculation of 13C NMR, and DP4+ probability analysis. Among all the isolates, eurylene (7), a constituent of the Malaysian medicinal plant Eurycoma longifolia, was obtained from a microbial source for first time. In the in vitro bioassay, 11 and 13 showed potent inhibitory activity against the Escherichia coli ß-glucuronidase (EcGUS) with IC50 values of 27.75 ± 0.73 and 17.73 ± 0.81 µM, respectively. It was the first time that questinol (11) and (±)-aspertertone B (13) were reported as potent EcGUS inhibitors.


Assuntos
Aspergillus , Estrutura Molecular , Aspergillus/química , Espectrometria de Massas , Espectroscopia de Ressonância Magnética
8.
Angew Chem Int Ed Engl ; 62(33): e202307475, 2023 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-37318899

RESUMO

The brain-storm of designing low-cost and commercialized eutectic electrolytes for zinc (Zn)-based electrochemical energy storage (ZEES) remains unresolved and attractive, especially when implementing it at low temperatures. Here, we report an appealing layout of advancing chlorine-functionalized eutectic (Cl-FE) electrolytes via exploiting Cl anion-induced eutectic interaction with Zn acetate solutions. This novel eutectic liquid shows high affinity to collaborate with 1,3-dioxolane (DOL) and is prone to constitute Cl-FE/DOL-based electrolytes with a unique inner/outer eutectic solvation sheath for the better regulation of Zn-solvating neighboring and reconstruction of H-bonding. The side reactions are effectively restricted on Zn anodes and a high Coulombic efficiency of 99.5 % can be achieved over 1000 cycles at -20 °C with Zn//Cu setups. By prototyping scale-up Zn-ion pouch cells using the optimal eutectic liquid of 3ZnOAc1.2 Cl1.8 -DOL, we obtain improved electrochemical properties at -20 °C with a high capacitance of 203.9 F g-1 at 0.02 A g-1 in a range of 0.20-1.90 V and long-term cycling ability with 95.3 % capacitance retention at 0.2 A g-1 over 3,000 cycles. Overall, the proposal of ideal Cl-FE/DOL-based electrolytes guides the design of sub-zero and endurable aqueous ZEES devices and beyond.

9.
Molecules ; 28(9)2023 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-37175232

RESUMO

α-Glucosidase (AGS) inhibitors have been regarded as an ideal target for the management of type 2 diabetes mellitus (T2DM) since they can maintain an acceptable blood glucose level by delaying the digestion of carbohydrates and diminishing the absorption of monosaccharides. In the process of our endeavor in mining AGS inhibitors from natural sources, the culture broth of two mangrove-derived actinomycetes Streptomyces sp. WHUA03267 and Streptomyces sp. WHUA03072 exhibited an apparent inhibitory activity against AGS. A subsequent chemical investigation into the two extracts furnished 28 secondary metabolites that were identified by spectroscopic methods as two previously undescribed linear polyketides 1-2, four benzenoid ansamycins 3-6, fourteen cyclodipeptides 7-18, one prenylated indole derivative 19, two fusicoccane-type diterpenoids 20-21, two hydroxamate siderophore 22-23, and five others 24-28. Among all of the isolates, 11 and 24 were obtained from actinomycetes for the first time, while 20-21 had never been reported to occur in a marine-derived microorganism previously. In the in vitro AGS inhibitory assay, compounds 3, 8, 9, 11, 14, 16, and 17 exhibited potent to moderate activity with IC50 values ranging from 35.76 ± 0.40 to 164.5 ± 15.5 µM, as compared with acarbose (IC50 = 422.3 ± 8.4 µM). The AGS inhibitory activity of 3, 9, 14, 16, and 17 was reported for the first time. In particular, autolytimycin (3) represented the first ansamycin derivative reported to possess the AGS inhibitory activity. Kinetics analysis and molecular docking were performed to determine the inhibition types and binding modes of these inhibitors, respectively. In the MTT assay, 3, 8, 9, 11, 14, 16, and 17 exhibited no apparent cytotoxicity to the human normal hepatocyte (LO2) cells, suggesting satisfactory safety of these AGS inhibitors.


Assuntos
Actinobacteria , Diabetes Mellitus Tipo 2 , Streptomyces , Humanos , Inibidores de Glicosídeo Hidrolases/química , Actinobacteria/metabolismo , Actinomyces/metabolismo , Simulação de Acoplamento Molecular , Streptomyces/metabolismo , alfa-Glucosidases/metabolismo , Estrutura Molecular
10.
Small ; 18(21): e2200550, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35289487

RESUMO

Rechargeable zinc batteries (RZBs) have proved to be promising candidates as an alternative to lithium-ion batteries due to their low cost, inherent safety, and environmentally benign features. While designing cost-effective electrolyte systems with excellent compatibility with electrode materials, high energy/power density as well as long life-span challenge their further application as grid-scale energy storage devices. Eutectic electrolytes as a novel class of electrolytes have been extensively reported and explored taking advantage of their feasible preparation and high tunability. Recently, some perspectives have summarized the development and application of eutectic electrolytes in metal-based batteries, but their infancy requires further attention and discussion. This review systematically presents the fundamentals and definitions of eutectic electrolytes. Besides, a specific classification of eutectic electrolytes and their recent progress and performance on RZB fields are introduced as well. Significantly, the impacts of various composing eutectic systems are disserted for critical RZB chemistries including attractive features at electrolyte/electrode interfaces and ions/charges transport kinetics. The remaining challenges and proposed perspectives are ultimately induced, which deliver opportunities and offer practical guidance for the novel design of advanced eutectic electrolytes for superior RZB scenarios.

11.
Zhongguo Zhong Yao Za Zhi ; 47(2): 392-402, 2022 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-35178981

RESUMO

Obvious epigenetic differentiation occurred on Lycium barbarum in different cultivation areas in China. To investigate the difference and change rule of DNA methylation level and pattern of L. barbarum from different cultivation areas in China, the present study employed fluorescence-assisted methylation-sensitive amplified polymorphism(MSAP) to analyze the methylation level and polymorphism of 53 genomic DNA samples from Yinchuan Plain in Ningxia, Bayannur city in Inner Mongolia, Jingyuan county and Yumen city in Gansu, Delingha city in Qinghai, and Jinghe county in Xinjiang. The MSAP technical system suitable for the methylation analysis of L. barbarum genomic DNA was established and ten pairs of selective primers were selected. Among amplified 5'-CCGG-3' methylated sites, there were 35.85% full-methylated sites and 39.88% hemi-methylated sites, showing a high degree of epigenetic differentiation. Stoichiometric analysis showed that the ecological environment was the main factor affecting the epigenetic characteristics of L. barbarum, followed by cultivated varieties. Precipitation, air temperature, and soil pH were the main ecological factors affecting DNA methylation in different areas. This study provided a theoretical basis for the analysis of the epigenetic mechanism of L. barbarum to adapt to the diffe-rent ecological environments and research ideas for the introduction, cultivation, and germplasm traceability of L. barbarum.


Assuntos
Lycium , China , Metilação de DNA , Primers do DNA , Epigênese Genética , Lycium/genética
12.
J Chem Phys ; 154(18): 184501, 2021 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-34241040

RESUMO

Deep eutectic solvents (DESs) and dilutions thereof (mainly in H2O but also in many other non-aqueous solvents and co-solvent mixtures) have recently attracted great attention. It is well known that DES dilutions exhibit deviations from ideality. Interestingly, the treatment of DES as a mixture of two components or a pseudo-component is by no means trivial when determining deviations in density and, mainly, in viscosity. Herein, we studied aqueous dilutions of one of the most widely studied DES, this is, that composed of choline chloride and urea in a 1:2 molar ratio (e.g., ChCl2U). Using density and viscosity data reported in previous works, we calculated the excess molar volumes (VE) and excess viscosities (ln ηE) considering ChCl2U as either a mixture of two components or a pseudo-component, that is, taking the DES molecular weight as MChCl2U = fChClMChCl + fUMU = 86.58 g mol-1 (with fChCl = 1/3 and fU = 2/3) or as M* ChCl2U = MChCl + 2 MU = 259.74 g mol-1. We found that neither the sign of VE and VE* nor their evolution with temperature was influenced by the use of either MChCl2U or M* ChCl2U, and only the absolute magnitude of the deviation and the DES content (in wt. %) at which the minimum appears exhibited some differences. However, ln ηE and ln ηE* exhibited opposite signs, negative and positive, respectively. The odd achievement of negative ln ηE in aqueous dilutions of ChCl2U characterized by the formation of HB networks suggest the treatment of ChCl2U as a pseudo-component as more appropriate. Moreover, the role played by the presence of U in the evolution of ln ηE* with temperature was also discussed.

13.
ChemSusChem ; 13(22): 5983-5995, 2020 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-32924284

RESUMO

High-performance energy-storage devices are receiving great interest in sustainable terms as a required complement to renewable energy sources to level out the imbalances between supply and demand. Besides electrode optimization, a primary objective is also the judicious design of high-performance electrolytes combining novel ionic liquids (ILs) and mixtures of aqueous solvents capable of offering "à la carte" properties. Herein, it is described the stoichiometric addition of a zwitterion such as betaine (BET) to protic ILs (PILs) such as those formed between methane sulfonic acid (MSAH) or p-toluenesulfonic acid (PTSAH) with ethanolamine (EOA). This addition resulted in the formation of zwitterionic-based PILs (ZPILs) containing the original anion and cation as well as the zwitterion. The ZPILs prepared in this work ([EOAH]+ [BET][MSA]- and [EOAH]+ [BET][PTSA]- ) were liquid at room temperature even though the original PILs ([EOAH]+ [MSA]- and [EOAH]+ [PTSA]- ) were not. Moreover, ZPILs exhibited a wide electrochemical stability window, up to 3.7 V vs. Ag wire for [EOAH]+ [BET][MSA]- and 4.0 V vs. Ag wire for [EOAH]+ [BET][PTSA]- at room temperature, and a high miscibility with both water and aqueous co-solvent (WcS) mixtures. In particular, "WcS-in-ZPIL" mixtures of [EOAH]+ [BET][MSA]- in 2 H2 O/ACN/DMSO provided specific capacitances of approximately 83 F g-1 at current densities of 1 A g-1 , and capacity retentions of approximately 90 % after 6000 cycles when operating at a voltage of 2.0 V and a current density of 4 A g-1 .

14.
ACS Appl Mater Interfaces ; 12(26): 29181-29193, 2020 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-32484323

RESUMO

Water-in-salt (WIS) electrolytes are gaining increased interest as an alternative to conventional aqueous or organic ones. WIS electrolytes offer an interesting combination of safety, thanks to their aqueous character, and extended electrochemical stability window, thanks to the strong coordination between water molecules and ion salt. Nonetheless, cost, the tendency of salt precipitation, and sluggish ionic transfer leading to poor rate performance of devices are some intrinsic drawbacks of WIS electrolytes that yet need to be addressed for their technological implementation. It is worth noting that the absence of "free'' water molecules could also be achieved via the addition of a certain cosolvent capable of coordinating with water. This is the case of the eutectic mixture formed between DMSO and H2O with a molar ratio of 1:2 and a melting point as low as -140 °C. Interestingly, addition of salts at near-saturation conditions also resulted in an increase of the boiling point of the resulting solution. Herein, we used a eutectic mixture of DMSO and H2O for dissolution of LiTFSI in the 1.1-8.8 molality range. The resulting electrolyte (e.g., the so-called aqueous-eutectic-in-salt) exhibited excellent energy and power densities when operating in a supercapacitor cell over a wide range of extreme ambient temperatures, from as low as -35 °C to as high as +65 °C.

15.
Micromachines (Basel) ; 10(1)2018 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-30583512

RESUMO

In this paper, we report a mid-wave infrared (MWIR) and long-wave infrared (LWIR) dual-band photodetector capable of voltage-controllable detection band selection. The voltage-tunable dual-band photodetector is based on the multiple stacks of sub-monolayer (SML) quantum dots (QDs) and self-assembled QDs. By changing the photodetector bias voltages, one can set the detection band to be MWIR, or LWIR or both with high photodetectivity and low crosstalk between the bands.

16.
J Hazard Mater ; 341: 10-19, 2018 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-28763632

RESUMO

The development of efficient solar driven catalytic system for the degradation of antibiotics has become increasingly important in environmental protection and remediation. Non-noble-metal NiS and MoS2 nanosheet co-modified graphitic C3N4 ternary heterostructure has been synthesized via a facile combination of hydrothermal and ultrasound method, and the ternary heterostructure has been utilized for photocatalytic degradation of antibiotic agents. The antibiotics of ciprofloxacin (CIP) and tetracycline hydrochloride (TC) were photodegraded by the hybrid under the visible light. The optimal photodegradation rate of the ternary heterostructure reaches about 96% after 2h irradiation, which is 2.1 times higher than that of pure g-C3N4 for TC degradation. The photocatalytic degradation rates of the ternary heterostructure for both CIP and TC obey the pseudo-first-order kinetic model. The enhanced visible light adsorption and charge separation efficiency contribute to the photocatalytic performance of the ternary heterostructure. This work provides new insights and pathways by which efficient degradation of antibiotics can be achieved and will stimulate further studies in this important field.


Assuntos
Antibacterianos/química , Dissulfetos , Grafite , Luz , Molibdênio , Nanocompostos , Níquel , Nitrilas , Compostos Azo/química , Ciprofloxacina/química , Corantes/química , Dissulfetos/química , Dissulfetos/efeitos da radiação , Grafite/química , Grafite/efeitos da radiação , Molibdênio/química , Molibdênio/efeitos da radiação , Nanocompostos/química , Nanocompostos/efeitos da radiação , Níquel/química , Níquel/efeitos da radiação , Nitrilas/química , Nitrilas/efeitos da radiação , Fotólise , Tetraciclina/química
17.
Environ Monit Assess ; 190(1): 15, 2017 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-29234976

RESUMO

Riverbed scour of bridge piers can cause rapid loss in foundation strength, leading to sudden bridge collapse. This study used multi-beam echo sounders (Seabat 7125) to map riverbed surrounding the foundations of four major bridges in the lower, middle, and upper reaches of the 700-km Yangtze River Estuary (YRE) during June 2015 and September 2016. The high-resolution data were utilized to analyze the morphology of the bridge scour and the deformation of the wide-area riverbed (i.e., 5-18 km long and 1.3-8.3 km wide). In addition, previous bathymetric measurements collected in 1998, 2009, and 2013 were used to determine riverbed erosion and deposition at the bridge reaches. Our study shows that the scour depth surrounding the bridge foundations progressed up to 4.4-19.0 m in the YRE. Over the past 5-15 years, the total channel erosion in some river reaches was up to 15-17 m, possessing a threat to the bridge safety in the YRE. Tide cycles seemed to have resulted in significant variation in the scour morphology in the lower and middle YRE. In the lower YRE, the riverbed morphology displayed one long erosional ditch on both sides of the bridge foundations and a long-strip siltation area distributed upstream and downstream of the bridge foundations; in the middle YRE, the riverbed morphology only showed erosional morphology surrounding the bridge foundations. Large dunes caused deep cuts and steeper contours in the bridge scour. Furthermore, this study demonstrates that the high-resolution grid model formed by point cloud data of multi-beam echo sounders can clearly display the morphology of the bridge scour in terms of wide areas and that the sonar technique is a very useful tool in the assessment of bridge scours.


Assuntos
Engenharia/métodos , Monitoramento Ambiental/métodos , Estuários , Sedimentos Geológicos/análise , Rios , Colapso Estrutural/prevenção & controle , China , Simulação por Computador , Materiais de Construção , Hidrodinâmica
18.
Zhongguo Zhong Yao Za Zhi ; 42(2): 264-273, 2017 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-28948729

RESUMO

To provide a scientific basis for the selection and optimization of the modern drying processing method for Angelicae Sinensis Radix (ASR). Three phenolic acids (esters), 6 phthalides were determined by using UPLC-PDA while polysaccharides were determined by UV-Vis spectrophotometry. Then the effects of drying methods on the inner qualities of ASR were evaluated through principle components analysis (PCA) combined with the appearance properties after drying. Results showed that the contents of chlorogenic acid and ferulic acid in samples obtained with controlled temperature and humidity drying (CTHD), medium and shortwave infrared drying (MSID) and microwave vacuum drying (MVD) methods were significantly higher than those with primary drying processing(PDP) method and the fresh samples. Multivariate statistical analysis showed that samples processed with CTHD had more similar general chemical properties with those processed with PDP, suggesting that CTHD was appropriate for the modern primary drying processing of ASR. With samples processed with traditional PDP method as reference, the CTHD method was further optimized in the processing parameters for ASR by orthogonal experiment design. Considering the consumption of drying power and time and other parameters, the modern drying parameters for the primary drying processing of ASR were finally optimized as follows: controlled temperature and humidity drying at 40-45 ℃, relative humidity below 25% and target moisture content about 50% in the first stage of drying process, tempering for 12-24 h, and then drying under the conditions of temperature at 50-60 ℃, relative humidity below 20% and fan frequency at 30-40 Hz in the second stage. The study provided the scientific evidence for the selection of appropriate drying method and suitable parameters for the modern primary drying processing of ASR, as well as the beneficial exploration and practice on the formation of technical standard of primary drying processing for roots and rhizomes types herbal medicines.


Assuntos
Angelica sinensis/química , Dessecação/métodos , Medicamentos de Ervas Chinesas/química , Raízes de Plantas/química , Plantas Medicinais/química , Análise de Componente Principal , Tecnologia Farmacêutica
19.
Sci Rep ; 7(1): 10996, 2017 09 08.
Artigo em Inglês | MEDLINE | ID: mdl-28887469

RESUMO

In this paper, we report the analysis of a concentric circular ring plasmonic optical antenna (POA) array using a simple lumped coupled circuit (LCC) model. The currents in the circular rings of the POA array and their mutual couplings are analyzed using the LCC model. The results agree well with the numerical simulation using CST's Microwave Studio®. The LCC model reveals the mutual couplings between the antenna rings. It is found that the mutual couplings are not only between the adjacent antenna rings, but also involve their second (2nd) nearest or farther neighbors. Since the near-fields of the optical antennas are related to the currents in the optical antennas, the LCC model provides a useful tool for the analysis of the near-field and their mutual interactions in the circular ring POA array.

20.
Dalton Trans ; 45(39): 15406-15414, 2016 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-27605133

RESUMO

Graphitic C3N4/ultrathin MoS2 (MoS2/g-C3N4) hybrids were synthesized via a facile bathing and ultrasound method. In this process, a well-bonded interface structure was formed between ultrathin MoS2 nanosheets and g-C3N4 through adjusting the amount of MoS2 in the MoS2/g-C3N4 hybrids. The MoS2/g-C3N4 hybrids were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), Raman spectroscopy (Raman), transmission electron microscopy (TEM) and UV-vis spectroscopy (UV-vis). The MoS2/g-C3N4 photocatalyst showed excellent photocatalytic activity in the photodegradation of organic pollutants. In this work, methyl orange (MO) was used as the simulative pollutant; the highest photodegradation rate (92.4%) was obtained when the amount of MoS2 was 5 wt% in the MoS2/g-C3N4 hybrids (0.05-MC), with a kinetic constant of 0.0189 min-1 after being irradiated under visible light for 2 h. Besides, 0.05-MC also showed excellent recyclability and chemical stability, and a photodegradation rate of 79.93% was reached after being reused 10 times. For practical pollutants, the photocatalytic degradation rates of ciprofloxacin (CIP) and tetracycline hydrochloride (TC) have been increased dramatically under the visible light irradiation. The excellent photocatalytic properties of MoS2/g-C3N4 hybrids can be ascribed to the enhanced separation rate and accelerated mobility of photogenerated charges through ultrathin MoS2 nanosheets' modification.

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