K-N Bridge-Mediated charge separation in hollow g-C3N4 Frameworks: A bifunctional photocatalysts towards efficient H2 and H2O2 production.

The development of bifunctional photocatalysts for enhancing hydrogen (H2) and hydrogen peroxide (H2O2) production from water is essential in addressing environmental and energy issues. However, the practical implementation of photocatalytic technology is still constrained by the inadequate separation of photo-generated charge carriers. Herein, potassium (K) atoms are introduced into the interlayers of graphitic carbon nitride (g-C3N4) with a hollow hexagonal structure (K-TCN) and are coordinated with N atoms in adjacent layers. The presence of K-N coordination serves as a layer bridge, facilitating the separation of charge carriers. The hollow hexagonal structure reduces the distance over which photogenerated electrons migrate to the surface, thereby enhancing the reaction kinetics. Consequently, the optimized K-TCN exhibits a dramatically improved photocatalytic H2 (941.6 µmol g-1h-1 with platinum (Pt) as the cocatalyst) and H2O2 (347.6 µmol g-1h-1) generation as compared to hollow g-C3N4 (TCN) and bulk g-C3N4 nanosheet (CN) without K-N bridge under visible light irradiation. The unique design holds promising potential for developing highly efficient bifunctional photocatalysts towards producing renewable fuels and value-added chemicals.

Synergy of MoO2 with Pt as Unilateral Dual Cocatalyst for Improving Photocatalytic Hydrogen Evolution over g-C3 N4.

Pt is usually used as cocatalyst for g-C3 N4 to produce H2 by photocatalytic splitting of water. However, the photocatalytic performance is still limited by the fast recombination of photo-generated electrons and holes, as well as the poor absorption of visible light. In this work, MoO2 /g-C3 N4 composites were prepared, in which MoO2 synergetic with Pt photo-deposited during H2 evolution reaction worked as unilateral dual cocatalyst to improve the photocatalytic activity. Within 4 hours of irradiation, the hydrogen production rate of MoO2 -Pt dual cocatalyst modified g-C3 N4 reached 3804.89 µmol/g/h, which was 120.18 times of that of pure g-C3 N4 (GCN, 31.66 µmol/g/h), 10.98 times of that of MoO2 modified g-C3 N4 (346.39 µmol/g/h), and 9.18 times of that of Pt modified g-C3 N4 (413.64 µmol/g/h). Characterization results demonstrate that the deficient MoO2 not only promoted visible light absorption of g-C3 N4 , but also worked as a "electron pool" to capture and transfer electrons to Pt.

[Efficacy difference between warming acupuncture and other acupuncture methods for primary obesity: a Meta-analysis].

OBJECTIVE: To systematically evaluate the efficacy difference between warming acupuncture and other acupuncture methods in the treatment of primary obesity. METHODS: A computer-based retrieval was conducted at PubMed, EMBASE, CENTRAL, CINAHL, Alt HealthWatch, CNKI, CBM, WANFANG database and VIP database. Retrieval time was from the establishment date of database to October 4, 2017. Randomized controlled trial (RCT) of warming acupuncture comparing with other acupuncture methods for the treatment of primary obesity were included. The relative risk (RR) and weighted mean difference (WMD ) were used as combined effects for categorical variables and continuous variables, respectively. RESULTS: Totally 13 RCTs were included involving 878 patients. The Meta-analysis indicated compared with other acupuncture methods, warming acupuncture could more reduce weight (WMD: -1.49 kg, 95% CI: -2.53 to -0.45, P=0.005), improve the total effective rate (RR=1.16, 95% CI: 1.09 to 1.24, P<0.000 01), reduce BMI (WMD: -1.24 kg/m, 95% CI: -2.34 to -0.14, P=0.03), reduce waist circumference (WMD: -1.65 cm, 95% CI: -2.53 to -0.76, P=0.02) and reduce hip circumference (WMD: -2.86 cm, 95% CI: -4.37 to -1.35, P=0.000 2), but had no significant influence on total cholesterol (WMD: -0.05 mmol/L, 95% CI:-0.98 to 0.88, P=0.91). CONCLUSION: The warming acupuncture has better efficacy on primary obesity than other acupuncture methods, but less effects on lipid indicators.

Hepatoprotective phenylethanoid glycosides from Cirsium setosum.

Two new phenylethanoid glycosides, namely ß-D-glucopyranoside, 1″-O-(7S)-7-(3-methoxyl-4-hydroxyphenyl)-7-methoxyethyl-3″-α-L-rhamnopyranosyl-4″-[(8E)-7-(3-methoxyl-4-hydroxyphenyl)-8-propenoate] (1) and ß-D-glucopyranoside, 1″-O-(7S)-7-(3-methoxyl-4-hydroxyphenyl)-7-methoxyethyl-3″-α-L-rhamnopyranosyl-4″-[(8E)-7-(4-hydroxyphenyl)-8-propenoate] (2), together with six phenylethanoid glycosides were isolated from Cirsium setosum. Their structures were elucidated by their spectroscopic data and references. Compounds 2, 4, 5, 7 and 8 (10 µM) exhibited moderate hepatoprotective activities. Compounds (3-8) were obtained from this plant for the first time.

Employing a new 12-connected topological open-framework copper borovanadate as an effective heterogeneous catalyst for oxidation of benzyl-alkanes.

A new 12-connected topological open-framework copper borovanadate with a unique B/V ratio (20/12) and a -B3O7(OH)-Na(µ-OH)[B(OH)2]-B3O7(OH)- connection mode has been hydrothermally obtained and characterized. It not only features the first 3-D copper(II) borovanadate which possesses the largest ratio of TM(2+) and borovanadate anion, but also displays highly catalytic activities for the oxidation of benzyl-alkanes.

Synthesis of BiOI@(BiO)2CO3 facet coupling heterostructures toward efficient visible-light photocatalytic properties.

In this paper, BiOI@(BiO)2CO3 facet coupling heterostructures were synthesized via exfoliation and ion exchange, and characterized by X-ray diffraction (XRD) patterns, scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HRTEM), UV-vis diffuse reflectance spectra (DRS), X-ray photoelectron spectroscopy (XPS), photoluminescence (PL) spectra and valence-band XPS spectra. With the reaction time increasing, more BiOI can be transformed to (BiO)2CO3, and BiOI@(BiO)2CO3 facet coupling heterostructures were obtained. The photocatalytic results showed that BiOI@(BiO)2CO3 displays much higher photocatalytic activity than BiOI and (BiO)2CO3 under visible-light. The photocatalytic mechanism study revealed that BiOI@(BiO)2CO3 has strong adsorption for RhB molecules due to the ultrathin nanosheets and higher BET, and displays better separation efficiency of photoinduced charge carriers and higher photocurrent due to the {001}/{001} facet coupling.

A Comparative Study of Contemporary Color Tongue Image Extraction Methods Based on HSI.

Tongue image with coating is of important clinical diagnostic meaning, but traditional tongue image extraction method is not competent for extraction of tongue image with thick coating. In this paper, a novel method is suggested, which applies multiobjective greedy rules and makes fusion of color and space information in order to extract tongue image accurately. A comparative study of several contemporary tongue image extraction methods is also made from the aspects of accuracy and efficiency. As the experimental results show, geodesic active contour is quite slow and not accurate, the other 3 methods achieve fairly good segmentation results except in the case of the tongue with thick coating, our method achieves ideal segmentation results whatever types of tongue images are, and efficiency of our method is acceptable for the application of quantitative check of tongue image.

[Extraction of fatty constituents from Tabanus bivittatus and their analysis by GC-MS].

OBJECTIVE: To optimize the extracting condition of fatty constituents from Tabanus bivittatus and analyse by GC-MS. METHODS: Taking fatty yield as index, the extraction technology parameters of fatty constituents of Tabanus bivittatus ere optimized by single factor test and orthogonal test. RESULTS: The optimum extraction parameters were as follows: the ratio of acetone to petroleum ether 1: 2, extraction time 2 h, solid-liquid ratio 1: 50. Twenty-one fatty acids were identified by GC-MS. CONCLUSION: The process is reasonable and with good reproducibility. The main components of fatty acids in Tabanus bivittatus are palmitoleic acid, palmitic acid, linoleic acid, oleic acid and stearic acid.

[A new method of automatic analysis of tongue deviation using self-correction].

The article analyzes the old analysis method of tongue deviation and introduces a new analysis method of it with self-correction avoiding the shortcomings of the old method. In this article, comparisons and analyses are made to current central axis extraction methods, and the facts proved that these methods were not suitable for central axis extraction of tongue images. To overcome the shortcoming that the old method utilized area symmetry to extract central axis so that it would lead to a failure to find central axis, we introduced a kind of shape symmetry analysis method to extract the central axis. This method was capable of correcting the edge of tongue root automatically, and it improved the accuracy of central axis extraction. In additional, in this article, a kind of mouth corner analysis method by analysis of variational hue of tongue images was introduced. In the experiment for comparison, this method was more accurate than the old one and its efficiency was higher than that of the old one.

Investigation of the retention mechanism of naphthol and benzenediol on calix[4]arene stationary phase based on quantum chemistry calculations.

Calixarenes are macrocyclic oligomers having the shape of a conical vase. Their inner cavity can accommodate various guest molecules, i. e. form supramolecules. Thus, calixarenes can be employed to manipulate selectivity in separation sciences. The essential step of separation is the interaction between calixarene and analytes. Therefore, in the present work, the retention mechanisms of benzenediol and naphthol positional isomers on a calix[4]arene column were investigated. The optimized supramolecular structures showed that there exist hydrogen bonding and pi-pi interactions for benzenediol, and for naphthol the pi-pi interactions dominate. Thermodynamic results from quantum chemistry calculations using DFT-B3LYP/STO-3G** basis set were consistent with the retention behaviors of benzenediol and naphthol positional isomers on the calix[4]arene column. This work will provide theoretical support for the design of new calixarene stationary phases.

Preparation and characterization of six calixarene bonded stationary phases for high performance liquid chromatography.

Six calixarene bonded silica gel stationary phases were prepared and characterized by elemental analysis, infrared spectroscopy and thermal analysis. Their chromatographic performance was investigated by using PAHs, aromatic positional isomers and E- and Z-ethyl 3-(4-acetylphenyl) acrylate isomers as probes. Separation mechanism based on the different interactions between calixarenes and analytes were discussed. The chromatographic behaviors of those analytes on the calixarene columns were influenced by the supramolecular interaction including pi-pi interaction, space steric hindrance and hydrogen bonding interaction between calixarenes and analytes. Notably, the presence of polar groups (-OH, -NO(2) and -NH(2)) in the aromatic isomers could improve their separation selectivity on calixarene phase columns. The results from quantum chemistry calculation using DFT-B3LYP/STO-3G* base group were consistent with the retention behaviors of PHAs on calix[4]arene column.

Simultaneous residue measurement of pendimethalin, isopropalin, and butralin in tobacco using high-performance liquid chromatography with ultraviolet detection and electrospray ionization/mass spectrometric identification.

A simultaneous residue analysis of pendimethalin, isopropalin, and butralin in tobacco was developed with high-performance liquid chromatography with ultraviolet monitoring and electrospray ionization mass spectrometry (HPLC-UV-ESI/MS). The herbicide residues of pendimethalin, isopropalin, and butralin in tobaccos were extracted by ultrasonication with ethyl acetate, followed by a cleanup procedure with gel permeation chromatography. The three herbicides were separated within 15 min using a LiChrosorb 18 column with methanol-10 mmol/L ammonium acetate (85:15, v/v) as the eluent. The limits of quantitation, using HPLC-UV, were ca. 0.05, 0.08, and 0.06 mg/kg for pendimethalin, isopropalin, and butralin, respectively, whereas the overall recoveries ranged from 77.5 to 91.8%. The proposed method has been successfully applied to measure 300 real samples, and the residue profiles of three herbicides in tobacco samples were obtained and evaluated.