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71.
Whey proteins are an important ingredient in the food industry. We have investigated the protein composition of commercial whey samples by liquid chromatography coupled to electrospray ionisation mass spectrometry on a time-of-flight instrument. We found that industrial whey protein contains a multitude of different modifications, ranging from almost native proteins through different degrees of glycosylation and oxidation up to almost completely oxidised forms. The information obtained allows characterisation of the influence of industrial processing on protein modifications and classification of whey protein-based ingredients or milk powders from different suppliers. 相似文献
72.
Doreen M Reich Susann Hau Tobias Stahl Markus Scholz Wilfried Naumann Frank Emmrich Johannes Boltze Manja Kamprad 《BMC neuroscience》2008,9(1):91
Background
The therapeutic capacity of human umbilical cord blood mononuclear cells (HsUCB-MNC) and stem cells derived thereof is documented in animal models of focal cerebral ischemia, while mechanisms behind the reduction of lesion size and the observed improvement of behavioral skills still remain poorly understood. 相似文献73.
An Easily Operating Polymer 1×4 Optical Waveguide Switch Matrix Based on Vertical Couplers 下载免费PDF全文
Kaixin Chen Pak L Chu Hau Ping Chan Kin S. Chiang 《中国物理快报》2007,24(6):1728-1730
A three-dimensional (3D) polymer thermo-optic (TO) 1 × 4 waveguide switch matrix based on vertical couplers is demonstrated. It consists of four basic 3D switch units and because of its 3D structure, its construction is compact, only 9 mm in length; moreover, the control logic of the entire switch is very simple, the light signal can be easily switched to any output port by operating only a single switch unit. The finished devices exhibit a switching extinction ratio greater than 21 dB for all of four output ports and the crosstalk between two adjacent output ports is lower than -19 dB. The rise time and the fall time of the switch matrix are 0.8ms and 1.4ms, respectively. The required electrical power to initiate the switching function for M1 switching units is about 50mW. 相似文献
74.
In Yung Sunwoo Jung Eun Kwon Trung Hau Nguyen Chae Hun Ra Gwi-Taek Jeong Sung-Koo Kim 《Applied biochemistry and biotechnology》2017,183(3):966-979
Conditions for ethanol production were evaluated using waste seaweed obtained from Gwangalli beach, Busan, Korea, after strong winds on January 15, 2015. Eleven types of seaweed were identified, and the proportions of red, brown, and green seaweed wastes were 26, 46, and 28%, respectively. Optimal pretreatment conditions were determined as 8% slurry content, 286 mM H2SO4 for 90 min at 121 °C. Enzymatic saccharification with 16 units/mL Celluclast 1.5L and Viscozyme L mixture at 45 °C for 48 h was carried out as optimal condition. A maximum monosaccharide concentration of 30.2 g/L was obtained and used to produce ethanol. Fermentation was performed with single or mixed yeasts of non-adapted and adapted Saccharomyces cerevisiae KCTC 1126 and Pichia angophorae KCTC 17574 to galactose and mannitol, respectively. The maximum ethanol concentration and yield of 13.5 g/L and YEtOH of 0.45 were obtained using co-culture of adapted S. cerevisiae and P. angophorae. 相似文献
75.
Ya‐Chu Hsieh Hau‐Yu Fang Yi‐Ting Chen Rong Yang Prof. Chen‐I Yang Prof. Pi‐Tai Chou Prof. Ming‐Yu Kuo Prof. Yao‐Ting Wu 《Angewandte Chemie (International ed. in English)》2015,54(10):3069-3073
The syntheses, structures, and physical properties of dibenzozethrenes were explored. The results thus obtained were compared with those for zethrenes. Dibenzozethrenes were synthesized by the nickel‐catalyzed cyclodimerization of 9‐ethynyl‐1‐iodoanthracenes. The substituents in zethrene and dibenzozethrene twisted their backbones, and remarkably influenced their properties. Unlike closed‐shell disubstituted derivatives, the parent zethrene and dibenzozethrene are singlet open‐shell biradicals, which were studied by variable‐temperature 1H NMR, ESR, SQUID and computational methods. Since substituents were observed to affect significantly the biradical properties, the relevant mechanisms were analyzed. The nonlinear optical performance of each of these compounds depends on its π‐conjugation and biradical properties. Dibenzozethrenes have larger two‐photon absorption cross‐sections than zethrenes, as most strongly evidenced by the parent dibenzothrene [σmax=4323 GM at 530 nm]. 相似文献
76.
A short synthesis of gabosine I (1) from delta-D-gluconolactone (3) in four steps, involving a one-pot TPAP oxidation-K2CO3-mediated intramolecular Horner-Wadsworth-Emmons (HWE) olefination as the key step, is described. Regioselective acetylation of the primary alcohol in gabosine I (1) then furnished gabosine G (2). 相似文献
77.
Han CY Willing GA Xiao Z Wang HH 《Langmuir : the ACS journal of surfaces and colloids》2007,23(3):1564-1568
In this work, it has been shown that, through a highly controlled process, the chemical etching of the anodic aluminum oxide membrane barrier layer can be performed in such a way as to achieve nanometer-scale control of the pore opening. As the barrier layer is etched away, subtle differences revealed through AFM phase imaging in the alumina composition in the barrier layer give rise to a unique pattern of hexagonal walls surrounding each of the barrier layer domes. These nanostructures observed in both topography and phase images can be understood as differences in the oxalate anion contaminated alumina versus pure alumina. This information bears significant implication for catalysis, template synthesis, and chemical sensing applications. From the pore opening etching studies, the etching rate of the barrier layer (1.3 nm/min) is higher than that of the inner cell wall (0.93 nm/min), both of which are higher than the etching rate of pure alumina layer (0.5-0.17 nm/min). The established etching rates together with the etching temperature allow one to control the pore diameter systematically from 10 to 95 nm. 相似文献
78.
Photocorrosion of Cuprous Oxide in Hydrogen Production: Rationalising Self‐Oxidation or Self‐Reduction 下载免费PDF全文
Cui Ying Toe Prof. Zhaoke Zheng Hao Wu Prof. Jason Scott Prof. Rose Amal Dr. Yun Hau Ng 《Angewandte Chemie (International ed. in English)》2018,57(41):13613-13617
Cuprous Oxide (Cu2O) is a photocatalyst with severe photocorrosion issues. Theoretically, it can undergo both self‐oxidation (to form copper oxide (CuO)) and self‐reduction (to form metallic copper (Cu)) upon illumination with the aid of photoexcited charges. There is, however, limited experimental understanding of the “dominant” photocorrosion pathway. Both photocorrosion modes can be regulated by tailoring the conditions of the photocatalytic reactions. Photooxidation of Cu2O (in the form of a suspension system), accompanied by corroded morphology, is kinetically favourable and is the prevailing deactivation pathway. With knowledge of the dominant deactivation mode of Cu2O, suppression of self‐photooxidation together with enhancement in its overall photocatalytic performance can be achieved after a careful selection of sacrificial hole (h+) scavenger. In this way, stable hydrogen (H2) production can be attained without the need for deposition of secondary components. 相似文献
79.
In Yung Sunwoo Nguyen Trung Hau Chae Hun Ra Gwi-Taek Jeong Sung-Koo Kim 《Applied biochemistry and biotechnology》2018,185(4):1075-1087
The optimal conditions for acetone–butanol–ethanol (ABE) production were evaluated using waste seaweed from Gwangalli Beach, Busan, Korea. The waste seaweed had a fiber and carbohydrate, content of 48.34%; these are the main resources for ABE production. The optimal conditions for obtaining monosaccharides based on hyper thermal (HT) acid hydrolysis of waste seaweed were slurry contents of 8%, sulfuric acid concentration of 138 mM, and treatment time of 10 min. Enzymatic saccharification was performed using 16 unit/mL Viscozyme L, which showed the highest affinity (Km?=?1.81 g/L). After pretreatment, 34.0 g/L monosaccharides were obtained. ABE fermentation was performed with single and sequential fermentation of Clostridium acetobutylicum and Clostridium tyrobutyricum; this was controlled for pH. A maximum ABE concentration of 12.5 g/L with YABE 0.37 was achieved using sequential fermentation with C. tyrobutyricum and C. acetobutylicum. Efficient ABE production from waste seaweed performed using pH-controlled culture broth and sequential cell culture. 相似文献
80.
Nguyen Van Hoa Nguyen Cong Minh Hoang Ngoc Cuong Pham Anh Dat Pham Viet Nam Pham Hau Thanh Viet Pham Thi Dan Phuong Trang Si Trung 《Molecules (Basel, Switzerland)》2021,26(20)
Dye and heavy metal contaminants are mainly aquatic pollutants. Although many materials and methods have been developed to remove these pollutants from water, effective and cheap materials and methods are still challenging. In this study, highly porous hydroxyapatite/graphene oxide/chitosan beads (HGC) were prepared by a facile one-step method and investigated as efficient adsorbents. The prepared beads showed a high porosity and low bulk density. SEM images indicated that the hydroxyapatite (HA) nanoparticles and graphene oxide (GO) nanosheets were well dispersed on the CTS matrix. FT-IR spectra confirmed good incorporation of the three components. The adsorption behavior of the obtained beads to methylene blue (MB) and copper ions was investigated, including the effect of the contact time, pH medium, dye/metal ion initial concentration, and recycle ability. The HGC beads showed rapid adsorption, high capacity, and easy separation and reused due to the porous characteristics of GO sheets and HA nanoparticles as well as the rich negative charges of the chitosan (CTS) matrix. The maximum sorption capacities of the HGC beads were 99.00 and 256.41 mg g−1 for MB and copper ions removal, respectively. 相似文献