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Eleven flavonoids including one new flavonol glycoside, quercetin-3-O-(2-α-L-rhamnopyranosyl)-β-D-glucuronopyranosyl methyl ester (1), were isolated for the first time from the fruits of Phyllanthus acidus (L.) Skeels (Phyllanthaceae). Their structures were determined by extensive spectroscopic data. The known flavonoids, quercetin-3-O-β-D-glucuronide methyl ester (3), quercetin-3-O-(2''-α-L-rhamnopyranosyl-6''-O-α-L-rhamno pyranosyl)-β-D-glucopyranoside (5), myricetin (9), and 6-methoxy-naringenin (11) were isolated for the first time from the genus Phyllanthus. Flavonoids 4, 6 and 9 (IC50 = 6.01, 6.32, and 7.84 μM, respectively) showed stronger α-glucosidase inhibitory activities than the positive control, acarbose (IC50 = 306.45 μM). The fruits of P. acidus might be further developed as an anti-diabetic food supplement.

Two new sphingofungins G (1) and H (2) with a five-membered lactone ring were identified from the solid-state fermentation of Aspergillus penicilliodes Speg., a dominant microorganism isolated previously from the post-fermentation of ripe Pu-er tea, together with six known metabolites. Their structures were elucidated by extensive spectroscopic methods. All of them were isolated from the mycelia culture of A. penicilliodes for the first time. The known compound, trypacidin, exhibited potent cytotoxities against five human cancer cell lines, e.g. myeloid leukemia HL-60, lung cancer A-549, hepatocellular carcinoma SMMC7721, breast cancer MCF-7, and colon cancer SW480, with IC50 values of 0.55, 11.45, 10.95, 3.58, and 3.49 μM, resp., while cisplatin as the positive control, with IC50 values of 8.63, 24.15, 21.99, 27.29, and 23.61 μM, resp.

Dasiphora fruticosa L. (Rosaceae), also known as Potentilla fruticosa L. (syn.), is a hardy deciduous shrub widely distributed in the north temperate regions of the world. Three methylene bisflavan-3-ols (1-3), together with a procyanidin dimer, (-)-afzelechin-(4α→8)-(-)-afzelechin (4) were isolated for the first time from the branches and leaves of the titled plant, in addition to 11 known compounds (5-15). Their structures were elucidated by means of extensive spectroscopic analysis and by comparison with data reported in the literatures. Methylene 6,8-bis(7-O-glucosyl) catechin (1) was determined to be a new dimeric flavan-3-ol glycoside through a methylene linkage between C-8 and C-8 of two units. At a concentration of 128 μg/mL, the known compounds 9 – 13 exhibited antibacterial activities on Escherichia coli, Staphylococcus aureus subsp. aureus, Salmonella enterica subsp. enterica, and Pseudomonas aeruginosa. Compound 12 also showed certain glucose uptake stimulating activity.

Zhejiang is a major province of energy consumption, but poor in energy resources. The inherent and complete dependence on importing energy makes energy security extremely difficult, which draws more attention to the energy conservation in Zhejiang. A great many factors of which the relations are complex affect the energy conservation. By introducing System Dynamics analysis, which has a unique advantage of analyzing the multiple and complex feedback system, this paper aims to analyze energy conservation in Zhejiang, and finally comes to some conclusions of values towards governments’ policies.

Arbutin (1), chlorogenic acid (2) and 6′-O-caffeoylarbutin (3) are three major components in Vaccinium dunalianum Wight with various promising bioactivities. A reliable, reproducible and accurate method for simultaneous and quantitative determination of 1–3 is developed by RP-HPLC analysis. This method should be appropriate for the quality assurance of unprocessed and processed materials of V. dunalianum. The contents of 1–3 in different parts of V. dunalianum from different origins were analysed. The content of 3 was much higher than those of 1 and 2, accounting for up to 31.76% in the dried leaf buds. Moreover, the leaf buds, flower buds and leaves showed a tendency towards higher contents of 1–3 than the other plant parts.

Fifteen known compounds including four triterpenoids (1–4), one sterol (5), one diketopiperazine alkaloid (6) and nine phenolics (7–15) were isolated from the stems of Piper wallichii. Their structures were elucidated by means of spectroscopic analysis, and acidic hydrolysis in case of the 2-oxo-3β,19α,23-trihydroxyurs-12-en-28-oic acid β-D-glucopyranosyl ester (1). The structure of compound 1 was fully assigned by 1D and 2D NMR experiments for the first time. All isolates were tested for their antibacterial, antifungal, anti-inflammatory and antiplatelet aggregation bioactivities.

The whole continuous columnsyn is a new kind of digital linear displacement sensor developed on the study of traditional linear inductosyn. The sensor structure is well-knit and it has excellent electrical and mechanical character. It thoroughly eliminated the inherent end-effect of traditional linear inductosyn. This article put forward a mathematical mode of the whole continuous columnsyn which has well-knit structure and excellent electrical & mechanical character according to the electromagnetic field theory and the analysed the electromagnetic field character of columnsyn sensor, distributing of field density and columnsyn magnetic-field. It also discussed the initial phase difference caused by the installation of winding of scale and slide and confirmed the key parameters of winding design. Based on above theory, the structure and related parameters of the prototype is designed and its partial performance is validated on the prototype.

Though the double cladding fiber (DCF) laser’s ability of heat dissipation is better than the traditional solid-state laser’s, the heat generation in double-cladding fiber laser is the bottleneck in the development of high power lasers. The distribution of heat deposition in the practical 400 W DCF laser is quantitatively analyzed for the first time. Based on the heat dissipation model developed in this work, in order to ensure the safe and stable operation of the kilowatt-level DCF laser, the convective coefficient near the pumping ends should be greater than 2.8×10-2W·cm-2K-1. The cooling device for high power DCF laser’s pumping ends was designed and successfully used in a laser system, and the output power of 1kW was obtained.

A new solid-state laser material——Yb：Y2O3 transparent ceramic based on nano crystalline technology and the vacuum sintering (NTVS) method is reported. The manufacture technology, the physical and chemical properties, the energy level split structure and the spectra characteristics of Yb：Y2O3 ceramic media are discussed and compared with those of Yb:YAG single crystal. Further more, with the compact active mirror laser (CAMIL) design, the laser parameters of Yb:Y2O3 ceramic are demonstrated at room temperature. An optimum output power of 10.5W has been obtained under the max imum pumping power of 35 W. Its corresponding slope efficiency was 37.5%. The laser wavelength red-shift was observed with the increasing of the pump power and the reflectivities while the decrease of the radium of output coupler (ROC). In fact, Yb：Y2O3 ceramic is an ideal laser material, it has excellent physical and chemical properties and spectra characteristics comparable with those of the Yb:YAG single crystal. Further more, its thermal conductivity and emission bandwidths are nearly twice those of Yb:YAG, which shows that it is a promising candidate in high power and femto-second pulsed laser applications.

The suppressing effect of laser extraction on the non-radiation transition process is taken into account when the heat model of gain media is developed. Based on the developed heat model, the heat generation in the operating LD side-pumped Nd:YAG ceramic lasers is quantified through using the normalized heating parameter, which can be deduced from the experimental results of the slope efficiency and the absorbed pumping power of the gain media. The main factors which influence on the heat generation are investigated by studying the normalized heating parameter, and the results show that the changes of the laser extraction efficiency, the beam overlap efficiency and the Nd3+ concentration will result in obvious variations of the normalized heating parameter. In this work, the laser extraction efficiency increases to 0.905 by the optimization of the transmission of the output coupling, and the normalized heating parameter decrease to 0.474, correspondingly.

The heat generation in Nd:YAG ceramic lasers under the conditions of laser extraction was investigated through the heat generation coefficient, which was defined as the ratio of heat generation power to laser output power. The heat generation coefficient of the 1.0% neodymium-doped YAG ceramic laser was calculated to be 0.63. The main factors which influences the heat generation coefficient were discussed in this paper, and the results showed that the heat generation coefficient was very sensitive to the changes in quantum emission efficiency, overlap efficiency and laser extraction efficiency. This work provides a reference for further research of thermal effect of Nd:YAG ceramic lasers.