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1.
Opt Express ; 30(5): 6700-6712, 2022 Feb 28.
Article in English | MEDLINE | ID: mdl-35299449

ABSTRACT

Magneto-optical (MO) properties of the bilayed Au/BIG and trilayered Au/BIG/Au magneto-plasmonic crystals (MPCs) were analyzed by the finite-difference time-domain method. In contrast to the low deflection angle and transmission of the smooth thin film, all the heterostructures with perforated holes in the top Au film displayed a similar trend with two strong resonant bands in Faraday rotation and transmittance in the near infrared wavelength range. The bands and electric distribution relative to the component and hole structure were revealed. The MPC with plasmonic hexagonal holes was found to own superior Faraday effects with distinctive anisotropy. The evolution of the resonant bands with the size and period of hexagonal holes, the thickness of different layers, and the incident light polarization was illustrated. The Faraday rotation of the optimized bilayed and trilayered hexagonal MPCs was improved 15.3 and 17.5 times, and the transmittance was enhanced 12.1 and 11.1 folds respectively at the resonant wavelength in comparison to the continuous Au/BIG film, indicating that the systems might find potential application in MO devices.

2.
Nano Lett ; 16(11): 7148-7154, 2016 11 09.
Article in English | MEDLINE | ID: mdl-27766883

ABSTRACT

High energy and power densities are the greatest challenge for all-solid-state lithium batteries due to the poor interfacial compatibility between electrodes and electrolytes as well as low lithium ion transfer kinetics in solid materials. Intimate contact at the cathode-solid electrolyte interface and high ionic conductivity of solid electrolyte are crucial to realizing high-performance all-solid-state lithium batteries. Here, we report a general interfacial architecture, i.e., Li7P3S11 electrolyte particles anchored on cobalt sulfide nanosheets, by an in situ liquid-phase approach. The anchored Li7P3S11 electrolyte particle size is around 10 nm, which is the smallest sulfide electrolyte particles reported to date, leading to an increased contact area and intimate contact interface between electrolyte and active materials. The neat Li7P3S11 electrolyte synthesized by the same liquid-phase approach exhibits a very high ionic conductivity of 1.5 × 10-3 S cm-1 with a particle size of 0.4-1.0 µm. All-solid-state lithium batteries employing cobalt sulfide-Li7P3S11 nanocomposites in combination with the neat Li7P3S11 electrolyte and Super P as the cathode and lithium metal as the anode exhibit excellent rate capability and cycling stability, showing reversible discharge capacity of 421 mAh g-1 at 1.27 mA cm-2 after 1000 cycles. Moreover, the obtained all-solid-state lithium batteries possesses very high energy and power densities, exhibiting 360 Wh kg-1 and 3823 W kg-1 at current densities of 0.13 and 12.73 mA cm-2, respectively. This contribution demonstrates a new interfacial design for all-solid-state battery with high performance.

3.
Int J Biol Macromol ; 277(Pt 1): 134092, 2024 Oct.
Article in English | MEDLINE | ID: mdl-39059523

ABSTRACT

Inhibition of pancreatic lipase (PL) is a strategy to prevent obesity. The inhibitory effects of Flos Sophorae Immaturus (FSI) extract and its main flavonoid components, rutin and quercetin, on PL were investigated. The contents of rutin and quercetin in FSI extract were 44.10 ± 1.33 % and 6.07 ± 1.62 %, respectively. The IC50 values of FSI extract, rutin and quercetin on PL were 322, 258 and 71 µg/mL, respectively. Rutin and quercetin inhibited PL in a reversible and noncompetitive manner. The combination of rutin and quercetin exhibited synergistic inhibitory effects at low concentration. The binding of rutin/quercetin with PL caused the fluorescence quenching of protein. Fluorescence titration showed the binding affinity of quercetin with PL protein was stronger than that of rutin. Circular dichroism analysis showed the binding changed the secondary structure of PL with an increase in random coil and a decrease in α-Helix and ß-Sheet. Molecular docking revealed that rutin and quercetin could interact with the amino acid residues around the catalytic site through multiple secondary interactions. In vivo studies showed that FSI extract can reduce fat absorption and promote fecal fat excretion through inhibition of PL activity, and the effects were mainly due to rutin and quercetin.


Subject(s)
Flavonoids , Lipase , Molecular Docking Simulation , Pancreas , Plant Extracts , Quercetin , Rutin , Lipase/antagonists & inhibitors , Lipase/metabolism , Lipase/chemistry , Plant Extracts/pharmacology , Plant Extracts/chemistry , Quercetin/pharmacology , Quercetin/chemistry , Pancreas/enzymology , Pancreas/drug effects , Flavonoids/pharmacology , Flavonoids/chemistry , Rutin/pharmacology , Rutin/chemistry , Animals , Enzyme Inhibitors/pharmacology , Enzyme Inhibitors/chemistry , Male , Sophora/chemistry
4.
Chem Commun (Camb) ; 60(10): 1285-1288, 2024 Jan 30.
Article in English | MEDLINE | ID: mdl-38197129

ABSTRACT

Herein, we reported an efficient indium catalyzed dithianyl-alkyne metathesis (DAM) reaction. This strategy allows for the formation of a new C-C double bond and valuable C-S bonds during the metathesis event, and was successfully applied to the synthesis of diverse vinyl dithianyl substituted organic molecules.

5.
Nanomaterials (Basel) ; 14(16)2024 Aug 15.
Article in English | MEDLINE | ID: mdl-39195386

ABSTRACT

In the extreme space environment, spacecraft endure dramatic temperature variations that can impair their functionality. A VO2-based smart radiator device (SRD) offers an effective solution by adaptively adjusting its radiative properties. However, current research on VO2-based thermochromic films mainly focuses on optimizing the emissivity tunability (Δε) of single-cycle sandwich structures. Although multi-cycle structures have shown increased Δε compared to single-cycle sandwich structures, there have been few systematic studies to find the optimal cycle structure. This paper theoretically discusses the influence of material properties and cyclic structure on SRD performance using Finite-Difference Time-Domain (FDTD) software, which is a rigorous and powerful tool for modeling nano-scale optical devices. An optimal structural model with maximum emissivity tunability is proposed. The BaF2 obtained through optimization is used as the dielectric material to further optimize the cyclic resonator. The results indicate that the tunability of emissivity can reach as high as 0.7917 when the BaF2/VO2 structure is arranged in three periods. Furthermore, to ensure a longer lifespan for SRD under harsh space conditions, the effects of HfO2 and TiO2 protective layers on the optical performance of composite films are investigated. The results show that when TiO2 is used as the protective layer with a thickness of 0.1 µm, the maximum emissivity tunability reaches 0.7932. Finally, electric field analysis is conducted to prove that the physical mechanism of the smart radiator device is the combination of stacked Fabry-Perot resonance and multiple solar reflections. This work not only validates the effectiveness of the proposed structure in enhancing spacecraft thermal control performance but also provides theoretical guidance for the design and optimization of SRDs for space applications.

6.
Nanomaterials (Basel) ; 14(13)2024 Jul 06.
Article in English | MEDLINE | ID: mdl-38998758

ABSTRACT

In recent years, smart windows have attracted widespread attention due to their ability to respond to external stimuli such as light, heat, and electricity, thereby intelligently adjusting the ultraviolet, visible, and near-infrared light in solar radiation. VO2(M) undergoes a reversible phase transition from an insulating phase (monoclinic, M) to a metallic phase (rutile, R) at a critical temperature of 68 °C, resulting in a significant difference in near-infrared transmittance, which is particularly suitable for use in energy-saving smart windows. However, due to the multiple valence states of vanadium ions and the multiphase characteristics of VO2, there are still challenges in preparing pure-phase VO2(M). Machine learning (ML) can learn and generate models capable of predicting unknown data from vast datasets, thereby avoiding the wastage of experimental resources and reducing time costs associated with material preparation optimization. Hence, in this paper, four ML algorithms, namely multi-layer perceptron (MLP), random forest (RF), support vector machine (SVM), and extreme gradient boosting (XGB), were employed to explore the parameters for the successful preparation of VO2(M) films via magnetron sputtering. A comprehensive performance evaluation was conducted on these four models. The results indicated that XGB was the top-performing model, achieving a prediction accuracy of up to 88.52%. A feature importance analysis using the SHAP method revealed that substrate temperature had an essential impact on the preparation of VO2(M). Furthermore, characteristic parameters such as sputtering power, substrate temperature, and substrate type were optimized to obtain pure-phase VO2(M) films. Finally, it was experimentally verified that VO2(M) films can be successfully prepared using optimized parameters. These findings suggest that ML-assisted material preparation is highly feasible, substantially reducing resource wastage resulting from experimental trial and error, thereby promoting research on material preparation optimization.

7.
Iran J Immunol ; 20(1): 129-134, 2023 Mar 14.
Article in English | MEDLINE | ID: mdl-36934323

ABSTRACT

Several cases of the hemolytic disease of the fetus and newborn (HDFN) caused by immunoglobulin G (IgG) anti-M antibodies have been reported, in which almost all the HDFN-associated anti-M were warmly reacting. Here we report two cases of severe HDFN associated with cold-reacting IgG anti-M. In both cases, pregnancy was terminated, in weeks 33 and 23 respectively, due to a diagnosis of fetal growth retardation (FGR). To our knowledge, these are the most severe HDFN cases caused by cold-reacting IgG anti-M.


Subject(s)
Blood Group Antigens , Erythroblastosis, Fetal , Pregnancy , Female , Infant, Newborn , Humans , Immunoglobulin G , Erythroblastosis, Fetal/diagnosis , Erythroblastosis, Fetal/etiology , Fetus
8.
Nanoscale Res Lett ; 17(1): 118, 2022 Dec 09.
Article in English | MEDLINE | ID: mdl-36484877

ABSTRACT

Structure has been considered to play an important role in photocatalytic performance of the semiconductors, but the intrinsic factors were rarely revealed. Herein, ZnO nanomaterials in the structures of thin film, nanowire array and nanosheet array were synthesized, and their structural characteristics, optical properties, photocurrent response and photocatalytic efficiency were compared with each other for illustrating the issue. The photoluminescence intensity decreased in the order of nanosheets, thin film and nanowires for improved lifetime of the photoexcited charges. The absorption of the nanosheets and nanowires improved obviously in the visible range with a redshift of the absorption edge than that of the thin film. The nanowires possessed the highest response current of 82.65 µA at a response time of 2.0 ms in a sensitivity of 87.93 at the light frequency of 1 Hz, and gained the largest catalytic efficiency of 2.45 µg/cm2 h for the methylene blue degradation in UV light. Nevertheless, the improvement of catalytic efficiency of the nanosheets (up to 42.4%) was much larger than that of nanowires (5.7%) and thin film (2.6%) for the Au coating. The analysis revealed that the photocatalytic efficiency of the ZnO nanomaterials was modulated by the structure as it contained different surface area, roughness, defect and doping states, vacancies, polar and non-polar crystalline faces, which would provide structural design of semiconductor nanomaterials for the photoelectric and photocatalytic applications.

9.
Org Lett ; 23(12): 4834-4837, 2021 Jun 18.
Article in English | MEDLINE | ID: mdl-34076451

ABSTRACT

A formal (4 + 1)-cycloaddition of vinylcyclopropanes and Et2SiH2 to afford 3,4-disubstituted silolanes is reported. The reaction sequence commences with the known B(C6F5)3-catalyzed alkene hydrosilylation with dihydrosilanes. Cleavage of the remaining Si-H bond in the hydrosilylation product assisted by B(C6F5)3 leads to formation of a cyclopropane-stabilized silylium ion. The activated cyclopropane ring is then opened by the in situ-generated borohydride accompanied by ring closure to the silolane. The diastereoselectivity is rationalized by a mechanistic model.

10.
Environ Sci Pollut Res Int ; 28(14): 17636-17647, 2021 Apr.
Article in English | MEDLINE | ID: mdl-33400121

ABSTRACT

In this work, copper hexacyanocobaltate was electro-deposited at amino-graphene-coated indium-tin-oxide glass to form multifunctional heterogeneous catalyst (CuCoG/ITO), which was confirmed by field emission scanning microscope, infrared spectra, X-ray diffraction, and electro-chemistry techniques. A novel heterogeneous photo-electro-Fenton-like system was established using CuCoG/ITO as an air-diffusion electrode, in which hydrogen peroxide (H2O2) and hydroxyl radical (•OH) could be simultaneously generated by air O2 reduction. The productive rate of •OH could reached to 70.5 µmol h-1 at - 0.8 V with 300 W visible light irradiation at pH 7.0, 0.1 M PBS. Levofloxacin could be quickly degraded at CuCoG/ITO during heterogeneous photo-electro-Fenton process in neutral media with a first-order kinetic constant of 0.49 h-1.


Subject(s)
Graphite , Water Pollutants, Chemical , Catalysis , Copper , Electrodes , Hydrogen Peroxide , Levofloxacin , Oxidation-Reduction , Water Pollutants, Chemical/analysis
11.
J Gen Appl Microbiol ; 56(2): 143-9, 2010 Apr.
Article in English | MEDLINE | ID: mdl-20513962

ABSTRACT

Strain LXD30(T) was isolated from rhizosphere soil of a plant of the species Camptotheca acuminata Decne which is native to warm, humid stream banks in southern China. Analysis of the 16S rRNA gene sequence revealed that the Gram-negative, rod-shaped bacterium fell within the realm of the genus Rhizobium and was most closely related to Rhizobium huautlense SO2(T) (96.4% sequence similarity) and Rhizobium cellulosilyticum LMG 23642(T) (96.4%). The isolate grew optimally at pH7.0 and 25-28 degrees C in the presence of 0-1% (w/v) NaCl. Major fatty acids were C16:0 (17.5%) and summed feature 7 (C18:1omega7c/omega9t/omega12t, 58.3%). Unequivocally low 16S rRNA (<97%), recA (<92%) and atpD (<90%) gene sequence similarities to all existing species of the genus and phenotypic characteristics all suggested that strain LXD30(T) (=KCTC 22609(T)=CGMCC 1.8903(T)) represents a novel Rhizobium species, for which the name Rhizobium kunmingense sp. nov. is proposed.


Subject(s)
Camptotheca/microbiology , Plant Roots/microbiology , Rhizobium/classification , Rhizobium/isolation & purification , Soil Microbiology , Bacterial Proteins/genetics , Bacterial Typing Techniques , China , DNA, Bacterial/analysis , DNA, Ribosomal/analysis , Genes, rRNA , Molecular Sequence Data , Phenotype , Phylogeny , RNA, Ribosomal, 16S/genetics , Rhizobium/genetics , Rhizobium/physiology , Sequence Analysis, DNA , Species Specificity
12.
Org Lett ; 22(18): 7383-7386, 2020 Sep 18.
Article in English | MEDLINE | ID: mdl-32903017

ABSTRACT

A hydrosilylation of vinylcyclopropanes (VCPs) catalyzed by the strong boron Lewis acid B(C6F5)3 is reported. For the majority of VCPs, little or no ring opening of the cyclopropyl unit is observed. Conversely, for VCPs with bulky R groups, such as ortho-substituted aryl rings or branched alkyl residues, ring opening is the exclusive reaction pathway. This finding is explained by the thwarted hydride delivery to a sterically shielded, ß-silicon-stabilized cyclopropylcarbinyl cation intermediate.

13.
Chem Commun (Camb) ; 56(30): 4188-4191, 2020 Apr 14.
Article in English | MEDLINE | ID: mdl-32167108

ABSTRACT

A highly chemoselective platinum-catalyzed mono-lateral diboration of dialkynylsilanes for the construction of silicon-tethered alkynyl diborylalkenes is described, in which tris(4-methoxyphenyl)phosphine was found to be an effective ligand for the cis-addition of diboron agents to the silicon-tethered alkynes, and the chiral ligand (AFSi-Phos)-mediated diboration of dialkynylsilanes resulted in the desymmetric construction of silicon-stereogenic centers with promising enantioselectivity.

14.
Chem Sci ; 12(2): 569-575, 2020 Oct 29.
Article in English | MEDLINE | ID: mdl-34163787

ABSTRACT

A trityl-cation-initiated annulation of benzyl-substituted vinylcyclopropanes (VCPs) with hydrosilanes is reported. Two Si-C(sp3) bonds and one C(sp2)-C(sp3) bond are formed in this process where an intramolecular 6-endo-tet Friedel-Crafts alkylation of a silylium-ion-activated cyclopropane ring is the rate-determining key step. The reaction mechanism is proposed based on computations and is in agreement with experimental observations. The new reaction leads to an unprecedented silicon-containing 6/6/5-fused ring system. A phenethyl-substituted VCP derivative yields another unknown tricycle having 6/6/6 ring fusion by reacting in a related but different way involving a 6-exo-tet ring closure.

16.
ACS Appl Mater Interfaces ; 10(35): 29909-29917, 2018 Sep 05.
Article in English | MEDLINE | ID: mdl-30047262

ABSTRACT

It is highly challenging to achieve an optically deformable polymer with good controllability, stability, and self-healability for fabricating an optically controlled microrobotics. Here, we present a photo-responsive self-healing supramolecular assembly cross-linked by 3,3',5,5'-azobenzenetetracarboxylic acid (t-Azo) enabling the controllable and stable deformation. The network (PAA-u) of polyacrylic acid (PAA) grafted with 2-ureido-4[1 H]-pyrimidinone (UPy) is formed via multiple intermolecular hydrogen bonds (H-bonds) between UPy and t-Azo moieties. Molecular H-bonds stabilize the cis-isomer, enables stress transfer at the interface, and also contributes to fast healability. The PAA-u/t-Azo assembly shows a green-light-induced bending deformation, which recovers its shape under the irradiation of UV light. On the basis of this controllable and reversible deformation, the PAA-u/t-Azo "hand" realizes reversible light-driven grabbing and releasing of an object by optimizing bending and recovery. The assembly also shows a fast and excellent self-healing performance irradiated by green light during deformation. The multiple-H-bonding-cross-linked assembly with stable deformation and fast self-healability can be used for the development of a multitude of advanced microrobotics.

17.
RSC Adv ; 8(31): 17325-17333, 2018 May 09.
Article in English | MEDLINE | ID: mdl-35539238

ABSTRACT

Amorphous red phosphorus/pyrolyzed bacterial cellulose (P-PBC) free-standing films are prepared by thermal carbonization and a subsequent vaporization-condensation process. The distinctive bundle-like structure of the flexible pyrolyzed bacterial cellulose (PBC) matrix not only provides sufficient volume to accommodate amorphous red-phosphorus (P) but also restricts the pulverization of red-P during the alternate lithiation/delithiation process. When the mass ratio of raw materials, red-P to PBC, is 70 : 1, the free-standing P-PBC film anode exhibits high reversible capacity based on the mass of the P-PBC film (1039.7 mA h g-1 after 100 cycle at 0.1C, 1C = 2600 mA g-1) and good cycling stability at high current density (capacity retention of 82.84% after 1000 cycles at 2C), indicating its superior electrochemical performances.

18.
Chem Commun (Camb) ; 54(22): 2727-2730, 2018 Mar 13.
Article in English | MEDLINE | ID: mdl-29411784

ABSTRACT

A fluorine-doped reduced graphene oxide (F-rGO), predominantly in the form of CF2 groups, was synthesized using the reduced-graphene-oxide precursor devoid of residual hydroxyl and carboxyl groups through a solvothermal process. The vacancies and defects accompanying the formation of the highly stable and electrochemically inert CF2 groups contribute to the excellent cycling stability of F-rGO, when it is applied as the anode material in a lithium-ion battery.

19.
Zhongguo Xue Xi Chong Bing Fang Zhi Za Zhi ; 31(3): 343-345, 2018 Jun 05.
Article in Zh | MEDLINE | ID: mdl-31544424

ABSTRACT

OBJECTIVE: To investigate the Blomia tropicalis breeding status in the ground dust rice collected in Haikou City. METHODS: Totally 17 samples of ground dust rice were collected from 10 sampling sites in Haikou City. Then 10 g of dust rice was taken from each individual sample for isolation of the mites that were made of slide specimen, and the mites were identified and classified under a microscope. RESULTS: B. tropicalis mites were found in all the 17 samples with the detection rate of 100%. A total of 1 176 heads of B. tropicalis were isolated, with an average breeding density of 6.91 heads/g. CONCLUSIONS: B. tropicalis breeding status is severe in Haikou City. The effective measures should be taken to prevent and control the harm associated with B. tropicalis contamination.


Subject(s)
Breeding , Mites , Oryza , Animals , China , Food Parasitology , Oryza/parasitology , Population Density
20.
RSC Adv ; 8(41): 22944-22951, 2018 Jun 21.
Article in English | MEDLINE | ID: mdl-35540169

ABSTRACT

To shed light on the influence of reaction parameters on palladium-catalyzed tandem allylic alkylation in the presence of Fei-Phos (a chiral trans-1,2-diaminocyclohexane-derived phosphine ligand), the effect of different phosphine ligands, inorganic or organic bases, Brønsted acids, and other additives on the asymmetric palladium-catalysed alkylation of catechol with allylic diacetate was investigated. In this reaction, 2-vinyl-2,3-dihydro-benzo[1,4]dioxin products with promising enantioselectivity were achieved in good yields. In addition, a novel palladium-catalyzed three-component and one-pot allylic substitution/cyclization/reduction reaction assisted by methylphenylsilane was reported with good selectivity.

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