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Using activated carbon (AC) with nano- lithium iron phosphate (LiFePO 4 ) as the positive and hard carbon (HC) as the negative, this type lithium-ion capacitor (LIC) has the inherent advantages in rate characteristics, cycle life and chemical stability, which is more suitable for rail transit application. As an indicator of capacitor available energy, state of energy (SOE) is of great importance to estimate. However, most of the models utilized in the literature concerning state estimation of LIC become problematic for outlining the characteristics without considering wide current magnification. In this work, a method, which is considering wide current magnification, is proposed for state of energy estimation of LIC.

Aspergillus niger CJ-1 was applied to conduct fermentation process on tartary buckwheat leaves (TBL), and effect of fermentation time on antioxidant ability and chemical compositions was revealed. Antioxidant ability of TBL showed a three-stage change tendency during fermentation, which was relatively consistent with change in chemical compositions. Rutin and quercetin were identified as remarkable contributors among fermentation. Both total polyphenols, rutin and quercetin was positively being correlated with antioxidant activity of TBL. Results indicated that fermentation time influenced antioxidant activity by altering content of TBL phenolic compounds, which showed a three-stage change law: augmenting at the early stage of fermentation, declining at the medium stage of fermentation, and slightly changing during the last stage. This tendency suggested that fermentation was a potent means to promote antioxidant capacity of agro-food unless fermentation time was controlled. This study may provide a theoretical basis for producing fermented foods with high bioactivity.

Phlorizin (PHZ), a type of dihydrochalcone widely found in Rosaceae such as apples, is the first compound discovered as a sodium-glucose cotransporter (SGLT) inhibitor. It has been confirmed to improve the symptoms of diabetes and diabetic complications effectively. Like other flavonoids, the bioavailability challenge of PHZ is the wide phase I and II metabolism in the digestive tract. In this study, we investigated the pharmacokinetics and contribution of phase II metabolism after the oral and intravenous administrations of PHZ in rats having type 2 diabetes (T2D) and in normal rats. The phase II metabolism characteristics of PHZ were investigated by treating plasma samples with β-glucuronidase/sulfatase. The contribution ratio of phase II metabolism of PHZ ranged from 41.9% to 69.0% after intravenous injection with three doses of PHZ in normal rats. Compared with the observations for normal rats, AUC0-t and Cmax of PHZ significantly increased and T1/2 of PHZ significantly decreased in T2D rats. PHZ was converted into phloretin (PHT) through an enzyme-catalyzed hydrolysis reaction, and PHT was further transformed into conjugates with glycose after both oral and intravenous administrations. Moreover, it was found that the bioavailability of PHZ was about 5% in T2D rats, which was significantly higher than that in normal rats (0%). In conclusion, compared with the observations for normal rats, the pharmacokinetic characteristics of PHZ significantly changed in T2D rats through oral and intravenous administrations. The bioavailability of PHZ significantly increased in T2D rats. Besides, the phase II metabolites of PHT were the major existing forms in blood after oral and intravenous administrations. Our results indicated that the phase II metabolism characteristics of PHZ should be considered when PHZ is applied for the treatment of diabetes as a drug or functional food.

Natural products generally contain complex and multiple bioactive compounds that are responsible for the effects on health through complicated synergistic and/or suppressive actions. As an important raw material of local ethnic minority tea, ethnomedicines and food supplements in southwestern areas of China, Docynia indica (Wall.) Decne (DID) mainly consists of phlorizin (PHZ), which is the main active component. In this study, the holistic activities and the interactions of components of PHZ, non-phlorizin (NP) in the DID extract (DIDE) were evaluated. A rapid and effective high-speed counter-current chromatography (HSCCC) was performed to knock out PHZ from DIDE and the purity of PHZ was 96.01% determined by HPLC, with a recovery rate of 96.76%. After 13 weeks of treatment course in a high-fat diet (HFD)-induced obese mice model, the results revealed that the DIDE and PHZ significantly decreased weight gain, blood lipid levels, hyperplasia of adipocytes and alleviated inflammation (p &lt, 0.05). Both DIDE and PHZ improves insulin resistance (p &lt, 0.001). Meanwhile, the intestinal barrier function was improved compared to HFD group, through the determination of serum lipopolysaccharides (LPS), glucagon-likepeptide-2 (GLP-2) and hematoxylin-eosin staining of jejunum. Interestingly, after NP treatment, the metabolic syndrome of the HFD-induced obesity appeared to have a similar improvement. All the experiments showed that there is a synergistic weakening phenomenon when PHZ and NP interact with each other in the mixed state. In conclusion, for the PHZ and NP showing a good effect on anti-obesity, anti-inflammation, and intestinal barrier function, DIDE could be a good source of functional food to prevent obesity.

Silicon film as a surface passivation layer is reported to reduce surface recombination on silicon nanowires (SiNWs) and thus enable to improve SiNW solar cell (SC) performance. A question yet to be answered regards the link between the silicon film assets and the solar cell performances. We investigated the effect of the properties of silicon films on the SiNWs SC performances by adjusting hydrogen dilution. Our results showed that the open-circuit voltage (Voc) and short-circuit current density (Jsc) of SiNWs SC increase until hydrogen dilution 10 and then decrease. An open-circuit voltage of 0.397 V and short-circuit current density of 18.42 mA/cm2 are achieved at optimized hydrogen dilution. Based on the analysis of silicon film properties we proposed that the increase of defect density with hydrogen dilution was the main cause for the deterioration of SiNWs SC performance.

We reported a ligand- and additive-free Cu(OAc)2/TEMPO catalyst system that enables efficient and selective aerobic oxidation of a broad range of primary and secondary benzylic alcohols, primary and secondary 1-heteroaryl alcohols, cinnamyl alcohols, and aliphatic alcohols to the corresponding aldehydes and ketones. This ambient temperature oxidation protocol is of practical features like aqueous acetonitrile as solvent, ambient air as the terminal oxidant, and low catalyst loading, presenting a potential value in terms of both economical and environmental considerations. Based on the experimental observations, a plausible reaction mechanism was proposed.

We reported an efficient ligand-free Co(OAc)2·4H2O/NaOH/O2/ethylene glycol reaction system that enables selective aerobic oxidation of a wide range of substrates covering 2,6-di-EWG-, 2,3,6-tri-EWG-, 2-EWG-, and 2-EWG-6-EDG-substituted 4-cresols into the corresponding 4-hydroxybenzaldehydes. Based on the experimental investigations and well-defined p-benzoquinone methides, a plausible reaction mechanism was proposed. Considering the simplicity of the procedure and importance of the products, the methodology was expected to become a favorable and practical tool in related benzylic C(sp3)–H functionalization chemistry.

To heteroepitaxally grow the crystalline cubic-GaN (c-GaN) film on the substrates with large lattice mismatch is basically important for fabricating the blue or ultra-violet laser diodes based on cubic group III nitride materials. We have obtained the crystalline c-GaN film and the heteroepitaxial interface between c-Gan and GaAs(001) substrate by the ECR Plasma-Assisted Metal Organic Chemical Vapor Deposition (PA-MOCVD) under low-pressure and low-temperature (∼600°C) on a homemade ECR-plasma Semiconductor Processing Device (ESPD). In order to decrease the growth temperature, the ECR plasma source was adopted as the activated nitrogen source, therefore the working pressure of MOCVD was decreased down to the region less than 1 Pa. To eliminate the damages from energetic ions of current plasma source, a Multi-cusp cavity-coupling ECR Plasma source (MEP) was selected to use in our experiment. To decrease the strain and dislocations induced from the large lattice mismatch between c-GaN and GaAs substrate, the plasma pretreatment procedure i.e., the initial growth technique was investigated. The experiment arrangements, the characteristics of plasma and the growth procedure, the characteristics of c-GaN film and interface between c-GaN and GaAs(001), and the roles of ECR plasma are described in this contribution.

A practical Cu(II)/TEMPO-catalyzed process oxidizes primary and secondary alcohols to the corresponding carbonyl compounds using air as the terminal oxidant.

We reported an efficient ligand-free Co(OAc)2·4H2O/NaOH/O2/ethylene glycol reaction system that enables selective aerobic oxidation of a wide range of substrates covering 2,6-di-EWG-, 2,3,6-tri-EWG-, 2-EWG-, and 2-EWG-6-EDG-substituted 4-cresols into the corresponding 4-hydroxybenzaldehydes. Based on the experimental investigations and well-defined p-benzoquinone methides, a plausible reaction mechanism was proposed. Considering the simplicity of the procedure and importance of the products, the methodology was expected to become a favorable and practical tool in related benzylic C(sp3)–H functionalization chemistry.

OBJECTIVE To establish the method for determining muscone in rat intestinal perfusate by GC-MS/MS and study its intestinal absorption kinetic characteristics in rats. METHOD The GC-MS/MS method was used to determine the content of muscone in rat intestinal circulation fluid. In situ intestinal circulation perfusion was adopted to study absorption kinetics of muscone in rats. RESULT Muscone was proved to be well absorbed in each section of small intestine. Its absorption rate constants (Ka) and the absorption rate (A) in the rat intestine showed duodenum > jejunum (P ileum (P < 0.01). Its Ka, A and t1/2 in rat small intestine was 0.990 h(-1) , 43.58% and 0.705h, respectively. CONCLUSION Muscone was well absorbed in each intestinal section, with duodenum better than jejunum (Ka, T1/2, P < 0.05) significantly better than ileum (Ka, T1/2, P < 0.01; A, P < 0.05). There is no obvious statistical difference between jejunum and ileum.

Infrared detection within the atmospheric window between 3 to 5μm has gained great interest because of its wide range of applications, such as eye-safe free-space optical communication links and high-precision time-of-flight measurements used in 3D imaging. In this letter, we report on the characteristics of two InP-based strain-compensated InGaAs/InAlAs quantum cascade detectors (QCDs) detecting around 4 μm and 4.5 μm, which are promising candidates for applications in this wavelength range. Maximal responsivity values of 11.43mA/W at 180K and 10.1 mA/W at 78K and Johnson noise limited detectivities of 2.43×10 10 and 2×10 10 Jones at 78K, for the 4.5 μm and the 4 μm device, respectively, were obtained. In addition, both devices can work up to room temperature with responsivities of 0.81 mA/W(4.5μm) and 1.64 mA/W(4μm).

Photocapacitance measurements were used to study the photoionization cross‐section spectra of holes in iron doped Alx Ga1−xAs. The spectra are well described by the crystal field theory giving a nearly constant crystal field splitting of about 0.36 eV for all compositions studied. As a result of an extended range of composition (0≤x≤0.76), it was possible to show that the binding energy of the dominant iron center increases linearly with composition and that the relative position of the center is not related to any of the conduction band minima. The variation of the energy for Γ1(5E)→Γ5(5T2) transition in Fe2+(3d6) is discussed for different host crystals.

DLTS spectra of deep level impurities in semiconductors often display anomalies such as zero offsets, steps or peaks with reversed signs. For a correct interpretation of the spectra it is important to understand those features. They are explained here, and shown to be related to the presence of free-carrier tails which extend into the depletion region of a semiconductor junction. Gold-doped silicon and the so-called A - and B -levels in GaAs are chosen for illustration of the effects.

A photocapacitance method was used to monitor the time dependences of the occupation numbers for the gold‐related donor and acceptor in silicon during optical excitation. The experimental data give strong evidence that the donor level corresponds to the +/0 transition and the acceptor to the 0/− transition for one single defect.

Concentration measurements using the electron paramagnetic resonance (EPR) signature of the Ni3+ (3d7) state in GaP have been compared with thermal emission and photocapacitance data measured on the same samples. These data combined with EPR photo-quenching measurements provide a definitive assignment of a state with a thermal activation energy for hole emission of 510 meV to the Ni3+ to Ni2+ transition. The optical threshold for the same transition is 520 meV and the cross section for thermal capture of a hole into Ni2+ is 1.3*10-16 cm2 at 240K.