Preparation and optical properties of CdTe/CdO center dot nH(2)O core/shell nano-composites in aqueous solution

The deposition of CdO center dot nH(2)O On CdTe nanoparticles was studied in an aqueous phase. The CdTe nanocrystals (NCs) were prepared in aqueous solution through the reaction between Cd2+ and NaHTe in the presence of thioglycolic acid as a stabilizer. The molar ratio of the Cd2+ to Te2- in the precursory solution played an important role in the photoluminescence of the ultimate CdTe NCs. The strongest photoluminescence was obtained under 4.0 of [Cd2+]/[Te2-] at pH similar to 8.2. With the optimum dosage of Cd(II) hydrous oxide deposited on the CdTe NCs, the photoluminescence was enhanced greatly. The photoluminescence of these nanocomposites was kept constant in the pH range of 8.0-10.0, but dramatically decreased with an obvious blue-shifted peak while the pH was below 8.0. In addition, the photochemical oxidation of CdTe NCs with cadmium hydrous oxide deposition was markedly inhibited.

Pendleton Artificial Reef: annual progress report presented to Southern California Edison Company

(PDF contains 82 pages.)

Effects of the Maryland hydraulic clam dredge on populations of the soft-shell clam, Mya arenaria: final contract report

Final report on a three year study designed to investigate the effects of the Maryland hydraulic escalator clam dredge on populations and recruitment of the soft-shell clam, Mya arenaria. Experimental plots were established in the Potomac river, Maryland, and were dredged ina commerical manner by removing only legal size clams. quarterly samples were taken in the experimental and control plots by means of a van Veen grab for juvenile clams and the hydraulic dredge for older, deeper burrowing clams. Sediment samples were taken at selected periods for organic carbon and grain size analysis. Clams were separated into two size-groups. (PDF contains 38 pages)

Hydrocarbon sensors for oil spill prevention and response, Seward, Alaska, April 8th-10th, 2008: workshop proceedings

During April 8th-10th, 2008, the Aliance for Coastal Technology (ACT) partner institutions, University of Alaska Fairbanks (UAF), Alaska SeaLife Center (ASLC), and the Oil Spill Recovery Institute (OSRI) hosted a workshop entitled: "Hydrocarbon sensors for oil spill prevention and response" in Seward, Alaska. The main focus was to bring together 29 workshop participants-representing workshop managers, scientists, and technology developers - together to discuss current and future hydrocarbon in-situ, laboratory, and remote sensors as they apply to oil spill prevention and response. [PDF contains 28 pages] Hydrocarbons and their derivatives still remain one of the most important energy sources in the world. To effectively manage these energy sources, proper protocol must be implemented to ensure prevention and responses to oil spills, as there are significant economic and environmental costs when oil spills occur. Hydrocarbon sensors provide the means to detect and monitor oil spills before, during, and after they occur. Capitalizing on the properties of oil, developers have designed in-situ, laboratory, and remote sensors that absorb or reflect the electromagnetic energy at different spectral bands. Workshop participants identified current hydrocarbon sensors (in-situ, laboratory, and remote sensors) and their overall performance. To achieve the most comprehensive understanding of oil spills, multiple sensors will be needed to gather oil spill extent, location, movement, thickness, condition, and classification. No single hydrocarbon sensor has the capability to collect all this information. Participants, therefore, suggested the development of means to combine sensor equipment to effectively and rapidly establish a spill response. As the exploration of oil continues at polar latitudes, sensor equipment must be developed to withstand harsh arctic climates, be able to detect oil under ice, and reduce the need for ground teams because ice extent is far too large of an area to cover. Participants also recognized the need for ground teams because ice extent is far too large of an area to cover. Participants also recognized the need for the U.S. to adopt a multi-agency cooperation for oil spill response, as the majority of issues surounding oil spill response focuses not on the hydrocarbon sensors but on an effective contingency plan adopted by all agencies. It is recommended that the U.S. could model contingency planning based on other nations such as Germany and Norway. Workshop participants were asked to make recommendations at the conclusion of the workshop and are summarized below without prioritization: *Outreach materials must be delivered to funding sources and Congressional delegates regarding the importance of oil spill prevention and response and the development of proper sensors to achieve effective response. *Develop protocols for training resource managers as new sensors become available. *Develop or adopt standard instrument specifications and testing protocols to assist manufacturers in further developing new sensor technology. *As oil exploration continues at polar latitudes, more research and development should be allocated to develop a suite of instruments that are applicable to oil detection under ice.

Studies on the nutrition of brackish water catfish - Chrysichthys nigrodigitatus . 1. Preliminary investigations on the probable use of vegetable oil in catfish feeds

Four groups of brackishwater catfish were fed four diets: N.F. (NIOMR formula 1 feed), A. B. and C. for seven weeks. Feeds N.F., A., B and C. contained 1.21% fish oil + 5.59% vegetable oil; 1.21% fish oil + 7.39% vegetable oil; 1.21% fish oil + 9.09% vegetable oil; 1.21% fish oil + 10.89% vegetable oil respectively. Results of feeding trial showed that growth was best in the group fed diets containing 10.89% vegetable oil and least in those containing 9.09% vegetable oil

Some experiments on commercial pond fish culture in the tidal mangrove area of Niger delta of Nigeria

A pilot fish culture project was initiated by Shell Petroleum Development Company of Nigeria Limited in 1981 with specific aims and objectives. Site selection, survey, pond construction method and fish production with regards to experiences gathered and gained, problems and solutions so far obtained are discussed. Trials of freshwater fish species to check their adaptability to brackishwater ponds were carried out and the promising results of the growth rate of these species when compared with the traditional local brackishwater species selected for culture are reported. The extension programme so far carried out is briefly described

Angular distribution and conversion of multi-keV L-shell X-ray sources produced from nanosecond laser irradiated thick-foil targets

An experimental study on the angular distribution and conversion of multi-keV X-ray sources produced from 2 ns-duration 527nm laser irradiated thick-foil targets on Shenguang II laser facility (SG-II) is reported. The angular distributions measured in front of the targets can be fitted with the function of f(theta) = alpha+ (1- alpha)cos(beta) theta (theta is the viewing angle relative to the target normal), where alpha = 0.41 +/- 0.014, beta = 0.77 +/- 0.04 for Ti K-shell X-ray Sources (similar to 4.75 keV for Ti K-shell), and alpha = 0.085 +/- 0.06, beta = 0.59 +/- 0.07 for Ag/Pd/Mo L-shell X-ray Sources (2-2.8 keV for Mo L-shell, 2.8-3.5 keV for Pd L-shell, and 3-3.8 keV for Ag L-shell). The isotropy of the angular-distribution of L-shell emission is worse than that of the K-shell emission at larger viewing angle (>70 degrees), due to its larger optical depth (stronger self-absorption) in the cold plasma side lobe Surrounding the central emission region, and in the central hot plasma region (emission region). There is no observable difference in the angular distributions of the L-shell X-ray emission among Ag, Pd, and Mo. The conversion efficiency of Ag/Pd/Mo L-shell X-ray sources is higher than that of the Ti K-shell X-ray sources, but the gain relative to the K-shell emission is not as high as that by using short pulse lasers. The conversion efficiency of the L-shell X-ray sources decrease, with increasing atomic numbers (or X-ray photon energy), similar to the behavior of the K-shell X-ray Source.

Cogeneración con gas natural en una empresa de tratamientos térmicos

[ES]Diseño de una instalación de cogeneración basada en un motor de combustible gas natural para una empresa de tratamientos térmicos y superficiales. Para satisfacer las necesidades energéticas de la planta, la potencia eléctrica la suministrará un alternador conectado al motor y, a su vez, la entalpía de los humos de escape del motor se aprovechará para la producción de vapor de agua, necesario para la actividad industrial de la empresa. Por otro lado, el calor que es necesario disipar de dicho motor se recuperará para el calentamiento de agua de red, con la finalidad de limpiar la taladrina de las piezas tratadas.