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101.
102.
Zhen Wang Xiaochen Ma Wenguang Zhou Min Min Yanling Cheng Paul Chen Jian Shi Qin Wang Yuhuan Liu Roger Ruan 《Applied biochemistry and biotechnology》2013,171(3):689-703
The aim of this study was to evaluate the use of hydrolysates from acid hydrolysis of four different oil crop biomass residues (OCBR) as low cost culture media for algae growth. The one-factor-at-a-time method was used to design a series of experiments to optimize the acid hydrolysis conditions through examining the total nitrogen, total phosphorus, chemical oxygen demand, and ammonia nitrogen in the hydrolysates. The optimal conditions were found to be using 3 % sulfuric acid and hydrolyzing residues at 90 °C for 20 h. The hydrolysates (OCBR media) produced under the optimal conditions were used to cultivate the two algae strains, namely UM258 and UM268. The results from 5 days of cultivation showed that the OCBR media supported faster algae growth with maximal algal biomass yield of 2.7 and 3 g/L, respectively. Moreover, the total lipids for UM258 and UM268 were 54 and 35 %, respectively, after 5 days of cultivation, which suggested that the OCBR media allowed the algae strains to accumulate higher lipids probably due to high C/N ratio. Furthermore, over 3 % of omega-3 fatty acid (EPA) was produced for the two algae strains. In conclusion, OCBR media are excellent alternative for algae growth and have a great potential for large-scale production of algae-based ingredients for biodiesel as well as high-value food and pharmaceutical products. 相似文献
103.
Wang W Rauchfuss TB Bertini L Zampella G 《Journal of the American Chemical Society》2012,134(10):4525-4528
The diiron hydride [(μ-H)Fe(2)(pdt)(CO)(4)(dppv)](+) ([H2](+), dppv = cis-1,2-C(2)H(2)(PPh(2))(2)) is shown to be an effective photocatalyst for the H(2) evolution reaction (HER). These experiments establish the role of hydrides in photocatalysis by biomimetic diiron complexes. Trends in redox potentials suggests that other unsymmetrically substituted diiron hydrides are promising catalysts. Unlike previous catalysts for photo-HER, [H2](+) functions without sensitizers: irradiation of [H2](+) in the presence of triflic acid (HOTf) efficiently affords H(2). Instead of sacrificial electron donors, ferrocenes can be used as recyclable electron donors for the photocatalyzed HER, resulting in 4 turnovers. 相似文献
104.
Bing Hu Min Min Wenguang Zhou Yecong Li Michael Mohr Yanling Cheng Hanwu Lei Yuhuan Liu Xiangyang Lin Paul Chen Roger Ruan 《Applied biochemistry and biotechnology》2012,166(7):1661-1673
The effects of exogenous CO2 on the growth and lipid accumulation of a local screened facultative heterotrophic microalgae strain Auxenochlorella protothecoides (UMN280) as well as nutrient removal from concentrated municipal wastewater stream (centrate) were examined in this study. A 12-day batch experiment was conducted with CO2 aeration at three levels, namely, 0%, 1%, and 5% (v/v) CO2 mixed with air, under light intensity of 60???mol/(m2 @@s). A two-stage growth pattern was observed. The first stage (first?Cfifth day) was dominated by heterotrophic growth in which organic carbon was the main carbon source. The second stage (6th?C12th day) was dominated by autotrophic growth in which exogenous CO2 had a positive effect on algal biomass accumulation. The addition of 5% CO2 was better than that of 1% CO2 on the biomass and lipid production. The uptakes of nutrients were similar between injection and no injection of CO2, except on phosphorus removal which was affected by the acidification of CO2. 相似文献
105.
Jiaguo Yu Wenguang Wang Bei Cheng Baibiao Huang Xiaoyang Zhang 《Research on Chemical Intermediates》2009,35(6-7):653-665
Hierarchically disorder sponge-like macro/mesoporous titania was prepared by adding distilled water dropwise to a coating of tetrabutyl titanate. The results reveal that the un-calcined samples show obvious photocatalytic activity and multi-modal pore-size distribution. With increasing calcination temperatures, the photocatalytic activity and crystallinity increase. At 400°C, the calcined sample shows the highest photocatalytic activity. Further increasing the calcination temperatures results in the decrease of photocatalytic activity due to the drastic decrease of specific surface areas. However, the 600°C-calcined sample exhibits the highest specific photocatalytic activity due to high anatase crystallinity. 相似文献
106.
Zhiyong Gao Ning Liu Dapeng Wu Wenguang Tao Fang Xu Kai Jiang 《Applied Surface Science》2012,258(7):2473-2478
Graphene-CdS (G-CdS) composites were synthesized through a simple solvothermal method. The formed CdS nanospheres were homogeneously scattered on the surface of graphene sheets. Fluorescence quenching effect of the G-CdS composites indicated effective transfer of photo-excited electrons from CdS to graphene, suppressed the recombination of photo-generated electron-hole pairs, so that the enhanced visible light induced photodegradation activity for Rhodamine B (RhB) was achieved. Based on the high photocatalytic activity and well stability, the G-CdS composite containing 70% CdS can be expected to be a practical visible light photocatalyst. 相似文献
107.
For fixed k ≥ 3, let Ek(x) denote the error term of the sum
, where
1. It is proved that if the Riemann hypothesis is true, then
,
. A short interval result is also obtained. 相似文献
108.
Amplified spontaneous emission (ASE) always occurs in high-power DF laser systems with master oscillator-power amplifier (MOPA) configuration. ASE not only reduces the energy extraction efficiency of the laser system, but also negatively influences its heat management. The interaction between the ASE flux and the coherent laser flux, as well as the effect of ASE on cuboid DF amplifiers, is studied using a finite difference method and an iterative arithmetic. In addition, the influence of ASE on coherent laser amplification is discussed in detail. 相似文献
109.
110.
Yue Liao Ning An Ning Wang Yinyu Zhang Junfei Song Jinxiong Zhou Wenguang Liu 《Macromolecular rapid communications》2015,36(24):2129-2136
A photocleavable terpolymer hydrogel cross‐linked with o‐nitrobenzyl derivative cross‐linker is shown to be capable of self‐shaping without losing its physical integrity and robustness due to spontaneous asymmetric swelling of network caused by UV‐light‐induced gradient cleavage of chemical cross‐linkages. The continuum model and finite element method are used to elucidate the curling mechanism underlying. Remarkably, based on the self‐changing principle, the photosensitive hydrogels can be developed as photoprinting soft and wet platforms onto which specific 3D characters and images are faithfully duplicated in macro/microscale without contact by UV light irradiation under the cover of customized photomasks. Importantly, a quick response (QR) code is accurately printed on the photoactive hydrogel for the first time. Scanning QR code with a smartphone can quickly connect to a web page. This photoactive hydrogel is promising to be a new printing or recording material.