Concentration and mean degree of polymerization of Rubus ellagitannins evaluated by optimized acid methanolysis     

Vrhovsek U  Palchetti A  Reniero F  Guillou C  Masuero D  Mattivi F 《Journal of agricultural and food chemistry》2006,54(12):4469-4475

Ellagitannins are a major class of phenolics largely responsible for the astringent and antioxidant properties of raspberries and blackberries. The Rubus ellagitannins constitute a complex mixture of monomeric and oligomeric tannins. Rubus oligomeric ellagitannins contain, beside the well-known ellagic acid and gallic acid moieties, the sanguisorboyl linking ester group. When exposed to acids or bases, ester bonds are hydrolyzed and the hexahydroxydiphenic acid spontaneously cyclizes into ellagic acid. This study describes a new, rapid procedure for the acid hydrolysis of Rubus ellagitannins in methanol, which results in maximal yield and enables the quantification of all the major reaction products. Additionally, the method provides the rationale for estimating the mean degree of polymerization of Rubus ellagitannins.  相似文献   

Effects of mechanical aeration on evaporation rate and water temperature in aquaculture ponds          下载免费PDF全文

Hisham A Abdelrahman  Claude E Boyd 《Aquaculture Research》2018,49(6):2184-2192

Water temperature and water loss by evaporation were monitored in control ponds and in ponds with different rates of aeration (9.2, 18.4, 27.6 and 36.9 kW/ha). The mean decrease in water temperature at 70‐cm depth was greater than that at the surface in aerated ponds than in control ponds. The greater the aeration rate, the cooler was water, both at the surface and at 70 cm. Evaporation rates were found to increase with greater aeration rate. Water loss increased by 32%–92% over 24‐hr periods in ponds with one to four 0.37‐kW Air‐O‐Lator aerators, respectively. The nutrient‐enriched control pond was more turbid, had cooler surface and deep water temperature, and had greater evaporation loss than the control pond without nutrient addition and less turbid water. But, aeration did not increase turbidity. Aeration can increase water loss from ponds and result in lower water temperature. Although aeration should not be used excessively in order to conserve water and reduce production cost, it is essential for many types of feed‐based aquaculture.  相似文献   

Evaluation of a modified palatine nerve block in canine rhinoscopy with biopsy     

K. Fizzano  A. Claude  T. Archer  L. Kuo  S. Hinz  B. Thames  J. Eells  M. Ross 《Veterinary anaesthesia and analgesia》2017,44(1):195.e2

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C8 cross transfer for the treatment of caudal brachial plexus avulsion in three dogs          下载免费PDF全文

Pierre Moissonnier  Claude Carozzo  Jean‐Laurent Thibaut  Catherine Escriou  Antoine Hidalgo  Stéphane Blot 《Veterinary surgery : VS》2017,46(1):136-144

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Evaluation of intraepidermal nerve fibres in the skin of normal and atopic dogs          下载免费PDF全文

Aurore Laprais  Stanley M. Dunston  Sheila M. F. Torres  Claude Favrot  Thierry Olivry 《Veterinary dermatology》2017,28(4):355-e80

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Characterization of Pterocarpus macrocarpus (pradoo wood) biochar and its effect on the retention properties of sandy soils in Northeast Thailand     

Siwaporn Siltecho  Nopmanee Suvannang  Juthamard Kaiphoem  Erika Medeiros  José Romualdo de Sousa Lima  Nattaporn Prakongkep  Robert Gilkes  Claude Hammecker 《Soil Use and Management》2022,38(2):1293-1306

Pradoo wood biochar has been tested in order to explore sustainable solutions to the development of agriculture on poor sandy soils in marginal areas in Northeast Thailand. Some basic physicochemical properties of biochar, for example pore size distribution, cation exchange capacity (CEC), specific surface area (SSA), and water and nutrient adsorption, were determined and compared to soil properties in order to determine appropriate biochar application to soil. Pradoo wood biochar showed important adsorption properties with high SSA, CEC and nutrient adsorption. The water retention properties were also improved on the dry end of the water retention curve. Phosphorous and ammonium adsorption–desorption isotherms were established and their respective affinity for the biochar surface was quantified, by the means of a retention index and thermodynamical parameters. We found that despite excellent retention properties, biochar needs to be added in large amounts (between 10 and 70 kg m⁻²) to soil to be able to modify noticeably the resulting soil properties.  相似文献