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1.
《Food Control》2015
The Technical Regulation of Good Practices for Brazilian Food Services (Regulamento Técnico de Boas Práticas para Serviços de Alimentação do Brasil) can be complemented by sanitary surveillance agencies at the state, district and municipal levels by tailoring it to location-specific requirements. The purpose of the present study was to survey sanitary legislation governing Brazilian Food Services. During the period from November 2011 to November 2012, a survey was conducted with the sanitary surveillance agencies from the various states, capitals and the Federal District. A previously prepared and tested tool was used for data collection, comprising 10 questions. Only 10 (19.2%) of the sanitary codes had been established prior to RDC Resolution n° 216/2004 and were not complementary. Of the legislation cited as complementary, only the states of Santa Catarina, Rio Grande do Sul and São Paulo and the capital of the state of São Paulo truly presented additional and location-specific aspects. No legislation that was specific to hospital kitchens was found. The majority of participating coordination, including the Evaluation List for Good Practices in Food Services, was also verified; however, it had not been published. In conclusion, a gap in sanitary surveillance services exists, which was caused by the lack of location-specific food service regulations. 相似文献
2.
3.
On structural and high temperature electrochemical properties of ZrO2 thin film coating on Zr metal produced by carbonate melt 总被引:1,自引:0,他引:1
Melt of NaCO3 can favor oxidation of Zr to form ZrO2 thin film on Zr surface, which is used to make Zr/ZrO2 oxidation/reduction electrode of pH sensor for testing elevated temperature aqueous solutions. Using SEM, EPMA, XPS, EXAFS
and HRTEM, we found that ZrO2 film is tightness and solid with 20 μm thickness composed by nanometer-sized monoclinic crystals. Zr/ZrO2 interface is characterized of zoning structure according to topography and chemical composition in five zones: oxygen-rich
ZrO2, ZrO2, oxygen-rich Zr metal, oxygen-bearing Zr and Zr from outmost to center. Melt oxidation process of Zr involved oxidation time,
air and temperature. The air is important effect on structural and electrochemical properties of ZrO2 thin film for making elevate temperature electrochemical sensor. If oxygen air largely presented in carbonate melting process,
ZrO2 thin film is not tightness and not for oxidation/reduction electrode. 相似文献
4.
《Calphad》2005,29(1):49-55
The high pressure modelling of condensed phases has mainly been a topic for geophysics, but there is an interest in modelling moderate pressure dependence also for materials science and engineering. The Murnaghan equation of state has been implemented in the Thermo-Calc software to represent the pressure-dependent part of the Gibbs energy. Recently it has been shown by Jacobs and Oonk that an equation of state derived from an empirical relationship between volume and isothermal bulk modulus can be applied to represent experimental data in volume–pressure–temperature space with equal or better accuracy then the Murnaghan equation of state. In this paper we extend this equation of state and show that a simpler expression for the Gibbs energy can be derived than that given by Jacobs and Oonk. The resulting expression for the Gibbs energy has been implemented in the Thermo-Calc software. 相似文献
5.
F-X域粘弹性波动方程保幅偏移 总被引:6,自引:1,他引:5
提出了一种利用粘弹性声波波动方程进行偏移的新方法。其基本思路是,修改成像条件,使修改后的成像方程中考虑振幅补偿,然后利用粘弹性、单程波动方程在F-X域对震源和接收点波场进行延拓,进而完成散射、透射等补偿。理论数据处理和实际地震资料处理表明,该方法理论基础可靠,处理效果明显,能较好地解决实际地质问题。 相似文献
6.
《Cement and Concrete Composites》2007,29(4):330-336
The relatively simple to measure ‘time constant’ is presented as an index for characterizing the level of corrosion experienced by steel in concrete. This communication, largely in the form of a technical note, explicitly illustrates that the time constant determined from electrochemical testing has significant merit for monitoring corrosion of steel in concrete, and appears to be insensitive to the area of electrode being probed. In this work, the time constant, κ, is determined following a galvanostatic excitation signal, revealing a good correlation between the value of κ and corrosion status across specimens of widely varying geometry. Although this notion has been suggested in the past, this work presents both a survey and consolidated review to indicate the utility of the parameter as an index to corrosion rate on-site. 相似文献
7.
总结了南海北部陆缘晚期(或浅层)油气藏的勘探技术和方法,指出晚期油气成藏具有海底麻坑、气烟囱、"地震模糊带"和"亮点"等地震异常特征,从地化特征上可划分为浅层生物气、成熟—高成熟热解气和高含CO2热解气等3种油气成藏类型.在研究新构造运动表现形式的基础上,分析了逆断层、正断层和底辟—走滑断层3个断层活动区的晚期油气成藏机理,指出断层晚期活动和后期快速沉降促进了油气的运移和再分配,晚期油气成藏主要沿莺歌海盆地莺东斜坡带、东方—乐东区和沿琼东南盆地二号断裂带及珠江口盆地坳陷边缘斜坡带等分布,有利于油气和天然气水合物的勘探. 相似文献
8.
Analysis of dinosaur samples by nuclear microscopy 总被引:2,自引:0,他引:2
Xiankang Wu I. Orli S. M. Tang Yiming Wang Xiaohong Wang Jieqing Zhu 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》1997,130(1-4):308-314
Several dinosaur bone and eggshell fossil samples unearthed at different sites in China were analyzed by means of nuclear microscopy. Concentrations and distributions of elements such as Na, Mg, Al, P, S, Ca, Cr, Mn, Fe, Cu, Zn, As, Br, Sr, Y, Ce, Pb and U, etc. were obtained for each sample. The results of quantitative PIXE and RBS analyses show unusually high concentrations of U and Ce in several samples obtained from a period near the K-T boundary (between Cretaceous and Tertiary periods, 65 million years ago), suggesting that some form of environmental pollution could be the cause of dinosaur extinction. 相似文献
9.
针对河套盆地开展了历时多年的水文地质环境地质调查,利用采集的298组浅层地下水样品以及收集并甄选的382个水文地质钻孔记录分析发现:河套盆地内95%的高砷地下水(As质量浓度10μg/L)集中在黄河决口、改道形成的古河道影响带及黄河决口扇裙带。其中,盆地南部首次发现了较为集中的高砷地下水,其分布范围与黄河北岸的晚更新世以来黄河决口、改道形成的4个大型决口扇,在空间上有着良好的对应关系。黄河古河道带及决口扇裙带表现为较强的还原环境及蒸发浓缩作用以及较弱的地表水补给强度。受pH值、含铁氧化物的还原性溶解等因素影响,决口扇裙带浅层地下水中砷的含量略低于平原中部黄河古河道带。结果表明:黄河古河道带及决口扇裙带特定的沉积环境控制着地下水的水文地球化学过程,进而对高砷地下水的分布具有决定性的作用。 相似文献
10.
小秦岭金矿田位于华北克拉通南缘的华熊地块北缘,发育有产出于不同走向剪切带内的金矿脉。但是,目前研究和认识对矿脉和剪切带、以及不同方向矿脉之间的构造关系并不清晰。选择小秦岭中部善车峪一带的典型NNE向矿脉开展构造变形与矿化特征研究。结果表明:NNE向金矿脉以右阶排列的石英脉透镜体为特征,主体产状为120°∠70°; 矿脉产出于与之近平行的左行逆冲剪切带内,并改造了早期近EW向剪切带,其所处构造应力场环境为近EW向水平伸展; 矿体的主要矿石矿物为方铅矿、黄铁矿、闪锌矿等多金属硫化物,这些金属矿物多呈条带状或条纹状沿剪切面理或小角度斜交的张剪性面理贯入,显示与左行逆冲变形同期形成的特征。构造变形序列和矿化特征对比分析显示,小秦岭地区NNE向矿脉叠加改造了近EW向矿脉,其构造应力场环境分别与早白垩世和晚三叠世区域应力场特征一致。前人对于岩浆作用、成矿流体和成矿时代等方面的研究结果认为,小秦岭地区经历了印支期和燕山期两期构造与成矿作用的叠加,从而推测NNE向金矿脉应形成于燕山期陆内构造变形阶段,而近EW向矿脉可能形成于印支期华北板块和扬子板块碰撞拼贴阶段。 相似文献