21 research outputs found
Implementation of Radio-Frequency Deflecting Devices for Comprehensive High-Energy Electron Beam Diagnosis
In next-generation light sources, high-brightness electron beams are used in a free-electron laser configuration to produce light for use by scientists and engineers in numerous fields of research. High-brightness beams are described for such light sources as having low transverse and longitudinal emittances, high peak currents, and low slice emittance and energy spread. The optimal generation and preservation of such high-brightness electron beams during the acceleration process and propagation to and through the photon-producing element is imperative to the quality and performance of the light source. To understand the electron beam's phase space in the accelerating section of a next-generation light source machine, we employed radio-frequency cavities operating in a deflecting mode in conjunction with a magnetic spectrometer and imaging system for both low (250 MeV) and high (1.2 GeV) electron energies. This high-resolution, high-energy system is an essential diagnostic for the optimization and control of the electron beam in the FERMI light source generating fully transversely and longitudinally coherent light in the VUV to soft x-ray wavelength regimes. This device is located at the end of the linear accelerator in order to provide the longitudinal phase space nearest to the entrance of the photon-producing beam-lines. Here, we describe the design, fabrication, characterization, commissioning, and operational implementation of this transverse deflecting cavity structure diagnostic system for the high-energy (1.2 GeV) regime
Phase Diagram and High Temperature Superconductivity at 65 K in Tuning Carrier Concentration of Single-Layer FeSe Films
Superconductivity in the cuprate superconductors and the Fe-based
superconductors is realized by doping the parent compound with charge carriers,
or by application of high pressure, to suppress the antiferromagnetic state.
Such a rich phase diagram is important in understanding superconductivity
mechanism and other physics in the Cu- and Fe-based high temperature
superconductors. In this paper, we report a phase diagram in the single-layer
FeSe films grown on SrTiO3 substrate by an annealing procedure to tune the
charge carrier concentration over a wide range. A dramatic change of the band
structure and Fermi surface is observed, with two distinct phases identified
that are competing during the annealing process. Superconductivity with a
record high transition temperature (Tc) at ~65 K is realized by optimizing the
annealing process. The wide tunability of the system across different phases,
and its high-Tc, make the single-layer FeSe film ideal not only to investigate
the superconductivity physics and mechanism, but also to study novel quantum
phenomena and for potential applications.Comment: 15 pages, 4 figure
Exigência de metionina mais cistina, com base no conceito de proteína ideal, em rações para alevinos de tilápia-do-nilo
Effects of Supplemental Microbial Phytase and Xylanase on the Performance of Broilers Fed Diets Based on Corn and Wheat
A floor-pen trial was conducted to evaluate the effect on broiler performance of adding phytase and xylanase, alone or in combination, to diets based on corn and wheat. A cohort cage trial was also conducted to determine the influence of treatments on tibia ash and nutrient utilization. Five diets were formulated and included a positive control (PC) containing adequate levels of available P and calcium; a negative control (NC) with reduced levels of available P and calcium; and three NC diets supplemented with phytase, xylanase or phytase plus xylanase. Weight gain and feed efficiency were depressed (P < 0.05) in birds fed the NC diet, but performance was improved to the level of birds fed the PC diet when the NC diet was supplemented with 500FTU/kg phytase. The addition of xylanase alone to the NC diet had no effect (P > 0.05) on broiler performance. However, the combination of xylanase and phytase improved the feed efficiency compared with the NC diet. Adding phytase to the NC diet improved (P < 0.05) the tibia ash contents. The addition of phytase and xylanase individually had no effect (P > 0.05) on energy metabolizability. However, when combined together, the two enzymes were additive in their effects on energy utilization. Individual additions of phytase and xylanase had no effect (P > 0.05) on ileal digesta viscosity, but the xylanase-phytase combination lowered (P<0.05) digesta viscosity compared with the NC diet. Enzyme treatments had no effects (P > 0.05) on the intestinal morphology and intestinal digesta counts of lactobacillus and anaerobic bacteria. Overall, these results suggest that combining phytase and xylanase in diets based on corn and wheat will be beneficial in terms of the feed efficiency and energy utilization of broilers
Tribological Property of Selective Laser Melting–Processed 316L Stainless Steel against Filled PEEK under Water Lubrication
Níveis de treonina digestível para suínos machos castrados, de alto potencial genético para deposição de carne, na fase de terminação Digestible threonine levels for high genetic potential lean deposition finishing barrows
Avaliou-se o efeito de níveis de treonina digestível em rações sobre o desempenho e características de cacaça de suínos machos castrados, selecionados geneticamente, para deposição de carne na carcaça, na fase de terminação. Foram utilizados 70 animais, com peso inicial de 59,00+1,25kg, distribuídos em delineamento experimental de blocos ao acaso, com cinco tratamentos, sete repetições e dois animais por unidade experimental, sendo que na distribuição dos animais, foi adotado como critério o peso inicial. Os tratamentos foram níveis de treonina na ração (0,480; 0,504; 0,528; 0,554 e 0,572% de treonina digestível). Não houve efeito (P>0,05) dos tratamentos sobre o ganho de peso, consumo de ração e conversão alimentar. Os níveis de treonina digestível não influenciaram (P>0,05) a porcentagem de carne e a espessura de toucinho na carcaça. Conclui-se que o nível de 0,480% de treonina digestível, correspondente a relação de treonina digestível:lisina digestível de 60%, atendeu as exigências de suínos machos castrados de alto potencial para deposição de carne na carcaça dos 60 aos 95kg.<br>An experiment was carried out to determine the effects of digestible threonine levels in ration on the performance and carcass traits of hogs genetically selected for lean deposition at finishing. Seventy barrows averaging an initial weight of 59.00+1.25kg were distributed in a randomized experimental block design with five treatments and seven replicates, being two animals per experimental unit. Initial weight was adopted as a criterion for animal distribution in the treatments, which were the levels of digestible treonine in the diet (0.480; 0.504; 0.528; 0.554; and 0.572%). No effect (P>0.05) was observed among the treatments on daily weight gain, daily feed intake, and feed conversion. Digestible threonine levels did not influence (P>0.05) lean and backfat thickness percentage. It can be concluded that the level of 0.480% of digestible treonine, corresponding to the rate digestible treonine:lysine 60%, supplied the requirments of high potential lean deposition barows from 60 to 95kg