Amine-functionalized zirconium metal–organic framework as efficient visible-light photocatalyst for aerobic organic transformations

An amine-functionalized zirconium metal–organic framework (MOF) was used as a visible-light photocatalyst for selective aerobic oxygenation of various organic compounds including alcohols, olefins and cyclic alkanes, at high efficiency and high selectivity. This study shows the great potential for design and application of MOF-based photocatalysts

Use of dry hydrolysate from squid and scallop product supplement in plant based practical diets for Pacific white shrimp Litopenaeus vannamei

A series of trials were designed to evaluate hydrolysates from waste streams of squid and scallop processing centers for the use in practical shrimp feeds. Towards this goal, three growth trials and a consumption trial were conducted to evaluate the use of dry hydrolysate from squid and scallop waste as specialty ingredients in commercial type feed formulations for Pacific white shrimp Litopenaeus vannamei. In the three six-week growth trials, the basal diet (35% crude protein, 8% lipid) consisted primarily of soybean meal (SBM), corn protein concentrate, corn starch, and whole wheat. In Trial 1, the basal diet was supplemented with 3%, 6%, and 9% from squid hydrolysate (Squ) or scallop hydrolysate (Sca) as well as two treatments using SBM which was impregnated with the hydrolysate prior to use. In Trial 2, the basal diet was supplemented with 3% Squ or Sca, shrimp but the shrimp were offered diets in slight excess to allow for possible increases in consumption of feeds. In Trial 3, Squ and Squid meal were compared at 6%. At the end of the three growth trials, no significant differences were found in final biomass, final mean weight, percent weight gain, feed conversion ratio, and survival. Additionally, a group of shrimp (3 g initial mean weight) were used to estimate consumption of the feeds over three 1-hour feedings over three days. Interestingly, the estimated feed intake of the basal diet was significantly higher than that of diets supplemented with 3% Squ or Sca. Results of the present study indicate that Squ and Sca as well as the SBM impregnated with Squ or Sca are good marine ingredients and can be used as feed ingredients. However, no evidence of improved feed intake or enhancement of growth were observed even though the diets were plant based. Statement of relevance In this study, a series of trials were used to assess the efficacy of dry hydrolysate from squid and scallop as well as traditional squid meal use in plant based practical diets designed for the Pacific white shrimp. These findings will be useful because the feed producers are interested in how specific produce may improve performance either as a nutrient source or attractant, particularly in diets that do not contain fishmeal. The conclusion provide valuable information that indicates feed manufacturer and researchers can use these hydrolysate products as feed ingredients in diets of shrimp, but no evidence for use of these products to improve the shrimp growth performance was observed

THE EFFECT OF HABITAT ON METHANE EMISSION FROM AN ALPINE WETLAND

Alpine wetland is a source for methane (CH4), an important greenhouse gas, but little is known about how this habitat influences the emission. To understand this wetland habitats were selected at the altitude of 3430 m a.s.l. (in National Wetland Nature Reserve of Zoige, Quingle - Tibetan Plateau) and the methane flux was measured with static chambers in three different sites, including hollows with Carex muliensis Hand - Mazz. and Eleocharis valleculosa Ohwi f. setosa (Ohwi) Kitagawa., grass hummocks composed of Kobresia tibetica Maxim, Cremanthodium pleurocaule R. D. Good, Potentilla bifurca L. and Pedicularis sp. We have found that in alpine wetland these habitats significantly affect CH, emissions in the onset (April, 2006) and peak (August, 2005) stages of growing season. Hollows covered with Carex muliensis and Eleocharis valleculosa had higher values of emission than grass hummocks built by several grass species. Slight difference of CH4 emission was found between two kinds of hollows with Carex muliensis and Eleocharis valleculosa. These results were consistent with the change of water table, which was found best correlated with CH4 emissions (r(2) = 0.43, P <0.01) in the peak stage of growing season. Directly measured shoot biomass and plant heights were best related to CH4 emissions (r(2) = 0.59, P <0.01). However, in the onset stage of growing season, variation of CH4 emission may not be simply ascribed to changes in water table and vegetation structure

Photoinduced Reactions between Pb₃O₄ and Organic Dyes in Aqueous Solution under Visible Light

Pb₃O₄ could react with organic dyes in aqueous solution under visible light irradiation, in which Pb₃O₄ was transformed into Pb₃(CO₃)₂(OH)₂ along with oxidation of the organic dyes. Cu²⁺ has considerable effect on the reaction. In the presence of Cu²⁺, MO (20 ppm) and RhB (10^–5 mol L^–1) were completely degraded under visible light within 6 and 20 min, respectively, while both Pb₃O₄ and Cu²⁺ keep almost stable during photodegradation. The mechanisms of the reactions with and without Cu²⁺ ions were studied. The photochemical system of Pb₃O₄ cooperating with Cu²⁺ ions is probably used for the treatment of organic pollutants in water under visible light

Influence of Surface States on the Evaluation of the Flat Band Potential of TiO₂

Flat band potential (<i>V</i>_fb) is one of the most important physical parameters to study and understand semiconductor materials. However, the influence of surface states on the evaluating <i>V</i>_fb of titanium oxide (TiO₂) and other semiconductor materials through a Mott–Schottky plot is ignored. Our study indicated that the influence of surface states should be introduced into the corresponding equivalent circuit even when the kinetic process did not occur. Ignoring the influence of surface states would lead to an underestimation of the space charge capacitance. Our paper would be beneficial for accurate determination of <i>V</i>_fb of semiconductor materials. We anticipate that this preliminary study will open new perspectives in understanding the semiconductor–electrolyte interface