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61.
Back Cover: Cofactor‐Free Light‐Driven Whole‐Cell Cytochrome P450 Catalysis (Angew. Chem. Int. Ed. 3/2015) 下载免费PDF全文
62.
Suk Soon Choi Hyun Min Lee Jeong Hyub Ha Dong Gyun Kang Chang Sup Kim Jeong Hyun Seo Hyung Joon Cha 《Applied biochemistry and biotechnology》2013,171(5):1170-1177
During wastewater treatment, phosphate removal is an important and challenging process; thus, diverse technologies, including those derived from biological means, have been devised for efficient phosphate removal. Although conventional biological methods are effective in decreasing wastewater phosphate levels to ~1 mg/L, long periods of microbial adaptation are required for effective phosphate removal, and the removal efficiency of these methods is relatively poor at lower phosphate concentrations. In the present work, we constructed a recombinant Escherichia coli with periplasmic-expressed phosphate-binding protein (PBP) and investigated its biological removal ability for low phosphate levels. We found that the PBP-expressing recombinant E. coli cells showed efficient (> 94 %) removal of phosphate at low concentrations (0.2–1.0 mg/L) in a treated cell mass-dependent manner. Collectively, we propose that our PBP-expressing recombinant whole-cell system could be successfully used during wastewater treatment for the biological removal of low concentrations of phosphate. 相似文献
63.
合成了侧链带有咔唑的N-丙烯酰氧己基咔唑(MACZ),通过自由基聚合得到聚N-丙烯酰氧己基咔唑(PMACZ),在四氢呋喃含10%三氟化硼乙醚与四氟化硼四丁基胺的混合电解质溶液中,直接阳极氧化PMACZ获得自支撑交联网状的聚(聚N-丙烯酰氧己基咔唑)(PPMACZ)薄膜.PPMACZ薄膜具有良好的氧化还原性和热稳定性,电导率为1.34×10-5S·cm-1.1HNMR和红外光谱表明PMACZ二次聚合反应发生在咔唑单元的3,6位上,荧光光谱表明PPMACZ薄膜是一种良好的蓝色发光材料. 相似文献
64.
Inside Back Cover: In Situ Synthesis of Self‐Assembled Gold Nanoparticles on Glass or Silicon Substrates through Reactive Inkjet Printing (Angew. Chem. Int. Ed. 2/2014) 下载免费PDF全文
65.
Ahmed Oueslati Hatem Ben Romdhane Vincent Martin Fréderic Schiets Régis Mercier Refaât Chaâbouni 《Journal of polymer science. Part A, Polymer chemistry》2011,49(9):1988-1998
A novel pentamethylated norbornadiene (NBD) based dianhydride, α,α′‐bis‐(3,4,5,6,7‐pentamethylcyclopenta‐2,4‐dienyl)meta‐xylene‐1,2‐dianhydride (3), was prepared from α,α′‐bis‐(pentamethylcyclopentadienyl)meta‐xylene (1) and acetylene dicarboxylic acid. The bis‐adduct formed via Diels–Alder reaction afforded tetra‐acid (2), which was chemically cyclodehydrated to lead the targeted dianhydride (3). New polyimides containing NBD moieties in the main chain were prepared from the dianhydride monomer (3) and various aromatic diamines. The chemical structure of the polymers was confirmed by both 1H and 13C NMR analysis. Their Molecular weights were also measured by SEC. All of these polyimides are soluble at room temperature in common organic solvents, such as chloroform, dichloromethane, THF, DMSO, DMF, and NMP, and show good thermal stabilities. The photochemical isomerization of the NBD into quadricyclane (QC) was investigated by UV/vis spectrophotometry from polymer films using visible sunlight as irradiation source. It was found that the kinetic rate of the conversion NBD‐QC which proceeded smoothly is a first kinetic order. The stored energies released by the transformation of QC groups into NBD ones of the irradiated polymer films were also evaluated by DSC measurement and were found to be around 90 kJ mol?1. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011 相似文献
66.
KwangHee Hong KyuSeok Song HyungKi Cha Mo Yang JongMin Lee ChangWo Lee GaeHo Lee 《Journal of Radioanalytical and Nuclear Chemistry》1999,241(3):533-541
The detection of radiocesium in microparticles was performed by using an ion trap mass spectrometer coupled with laser desorption
and ionization. Pulsed laser desorbed particle and the resulted ions were analyzed by an ion trap mass analyzer. The presence
of radiocesium, especially about137Cs, in microparticles was verified by single as well as successive particle analysis. The detection limit was reached to ≈ag/particle
level with a signal-to-background ratio of 4. The inhomogeneous distribution of particle size and the irregular shapes of
particle limit the quantitative evaluation of137Cs concentration in the microparticle. But this high sensitivity allows to monitor directly the radiocesium from small amounts
of a microparticle sample. 相似文献
67.
A novel thin layer cell equipped with thin layer gas electrode (TLGE) was studied as electrochemical gas sensor for the measurement of dissolved oxygen in water or aqueous solutions. The working electrode (TLGE) is a hydrophobic gas diffusing electrode placed between the cell electrolyte and the solution to be tested. The hydrophobic pores in TLGE serve as a gas chamber. After the sampling period, in which the partial pressure of dissolved oxygen in test solution becomes in equilibrium with that in the gas chamber, the TLGE is polarized with square wave or linear potential signal. Then the Faradaic charge (Q) consumed in depletion of the oxygen contained in pores of TLGE is measured. The main merits of this system are good linearity between the partial pressure of dissolved oxygen in test solution and Q, low zero-reading, negligible liquid-gas difference, convenient calibration and very low temperature coefficient (ca. 0.5%/°C). This technique can also be applied to the measurement of oxygen partial pressure in gas phases. 相似文献
68.
The forced-convection film condensation on a horizontal cylinder with wavy surface structure was performed by boundary-layer-approximation.
The local/mean heat fluxes were obtained for the effects of tube temperature, wave number, and wave amplitude. The mean heat
flux increases with decreasing wavy amplitude and tube temperatures. Furthermore, when β = 20 and α = 0.005, the mean heat
flux slightly increases from 1.1 to 3.6% compared with that of smooth tube, depending on tube temperature. 相似文献
69.
70.
Byeong Hee Hwang Jae Won Lee Hyung Joon Cha 《Applied biochemistry and biotechnology》2010,162(4):1187-1194
The polymerase chain reaction (PCR) technique is widely used for efficient detection of food-borne pathogens because of speed and specificity. However, PCR methods have focused mostly on species-specific detection. In the present work, we describe a PCR-based method for the simultaneous detection of all Vibrio species because lots of them are notorious food-borne human pathogens. We then combined this total detection method with specific detection of Vibrio cholerae pathogen. Using a degenerate primer set based on the sequence of the potassium uptake gene, trkA, we were able to successfully detect all Vibrio species. Specific detection of V. cholerae was also possible using primer sets based on putative flagellin sequence. Importantly, simultaneous total and species-specific Vibrio detection was possible using all two primer sets in a multiplexed PCR strategy. Thus, the PCR method we have developed is applicable to both simultaneous and two-step detection of total and specific Vibrio species. 相似文献