LNG气化站气化方案的选型配置分析

简述了LNG气化站的工艺流程和主要设备,详细介绍了LNG气化站中不同的气化加热设备。通过典型案例,对比分析了LNG气化站3种不同气化方案的选型配置。最后提出应针对LNG气化站需求选择适合的气化方案。     

液化天然气供应站气化器的选型

阐述LNG气化器的分类和特点。以西北某LNG调峰储气中心为例,对浸没燃烧式气化器、整体式气化器、水浴式气化器、空温式气化器的占地面积、投资、运行成本、总成本费用进行比较,给出合适的LNG气化器选型。     

LNG加压气化调峰站运行实践的研究

结合实际的LNG加压气化调峰站的生产运行实践,论述了LNG加压气化调峰站的工艺流程、低温烃泵及高压空温式气化器的配置与运行中存在的问题,分析了5种安全事故,提出了防范措施。     

LNG气化站的安全设计

简述了LNG的危险性和我国LNG气化站的发展现状,从设计标准、总平面布置、围堰区、LNG储罐、气化器、管道及管件、消防系统等方面论述了LNG气化站的安全设计。指出应尽快制定符合我国国情的LNG规范。     

LNG气化站的安全设计

简述了LNG的危险性和我国LNG气化站的发展现状,从设计标准、总平面布置、围堰区、储罐、气化器、LNG输送管道以及消防等方面论述了LNG气化站的安全设计。     

LNG气化站的安全设计

分析了LNG的危险性,从围堰区、LNG储罐、气化器、管道及管件、消防系统等方面对LNG气化站的安全设计进行了讨论,指出应尽快制定符合我国国情的LNG规范。     

液化天然气气化站设计的改进

目前国内液化天然气气化站的设计主要参照国外和国内LPG站的标准,还没有形成LNG气化站的设计规范。根据多个LNG气化站设计、建设和运行的经验,针对设计及运行中存在的问题,对LNG气化站的低温管道、出站管道、BOG储罐、储罐增压器、围堰、消防水系统及办公用房的设计进行改进,使工艺更趋合理,有利于安全运行和减少造价。     

液化天然气气化站的安全设计

探讨了LNG气化站内LNG储罐、气化器和管道系统、消防系统等设施的安全设计要点。     

LNG空温式气化器气化过程的数值分析

根据传热机理的不同,将低温LNG在空温式气化器内的流动过程分为3段,建立了各段内天然气传热的模型,进行了数值计算.建立的模型可为LNG气化站气化器选型及运行管理提供理论依据.     

液化天然气气化站预冷投运方案

结合某液化天然气（LNG）气化站工程实践,探讨了LNG气化站氮气预冷和天然气置换的方案、操作要点和经验。     

Vanadium in foods and in human body fluids and tissues

Using neutron activation analysis, vanadium was analysed in a range of foods, human body fluids and tissues. On the basis of these results and those of other workers, it was concluded that daily dietary intake amounts to some tens of micrograms. Analysis of body fluids (including milk, blood and excreta) and organs and tissues provided an estimate for the total body pool of vanadium in man of about 100 μg. Vanadium was not detectable in blood and urine at the level of 0.3 ng/g, while low levels were found in muscle, fat, bone, teeth and other tissues. The relationship between dietary intake to pulmonary absorption is discussed in relation to the occurrence of vanadium in man-made air particulates. The very low levels found in milks and eggs suggest minimal vanadium requirements in growth. The findings are discussed in the light of previous results and also in relation to the possible essentiality of vanadium.     

Iodine-129 in thyroid and urine in Ukraine and Denmark

Human thyroids collected from Gomel in Belarus, sheep thyroid from Jutland and human urine from Zealand in Denmark were analysed for 129I and 127I concentrations. The ratios of 129I/127I in human thyroid in Gomel are 2.65-11.0 x 10(-9) with an average of 7.21 x 10(-9), which is one order of magnitude higher than those from Asia and South America (10(-10)), but significantly lower than those observed in west Europe (10(-8)). A weak negative correlation (P < 0.05) between 129I/127I ratio in human thyroid and the age of the subjects was observed in Gomel. The average ratio of 129I/127I in sheep thyroids from Jutland of Denmark is 1.81 x 10(-7), which is two orders of magnitude higher than those in south hemisphere, and Asia. It is also significantly higher than those observed in other west European countries before 1984 and that in human thyroid in Gomel. The high thyroid 129I level in Jutland is attributed to the release of reprocessing plants in France and UK. The 129I/127I ratios in human urine in Zealand of Denmark are 0.86-2.86 x 10(-8). The possibility of using urine 129I to evaluate the thyroid exposure to 129I is investigated.     

儿童青少年近视的防控研究进展

儿童青少年近视率一直处于高位并持续上升,严重影响了我国儿童青少年的学习和生活,本研究通过查阅国内外治疗儿童青少年近视相关著作及文献,针对目前儿童青少年近视防控手段的进展,对各治疗方案进行分析和研究。     

德国城乡景观与中国景观问题

2003年,笔者获得德国DAAD(德国国际学术交流基金会)奖励资助,作为访问学者在德国逗留了4个月(4月～8月).在这期间,笔者还考察了法国、丹麦、瑞典和意大利,但我认为还是德国的景观最为优雅和美丽.     

广义文脉与规划设计教育

城市规划设计教育不仅应关注历史化,还应关注自然、社会和经济;不仅应关注地方和传统,还应关注全球和未来。城市规划教育应掌握正确的发展观和方法论,肩负起发展地万脉的历史使命,保护社会公众的利益,推动城市持续发展。     

Perchlorate in raw and drinking water sources in England and Wales

A well‐known use of perchlorate is as a rocket fuel propellant; however, more widespread uses include in munitions and fireworks, and it also occurs naturally. Perchlorate suppresses the thyroid, which can lead to a variety of adverse effects. It is a widespread contaminant in the United States, but limited occurrence data in the United Kingdom exist, and even less for drinking water. Monitoring of 20 raw and treated drinking water sites in England and Wales, covering four seasonal periods, showed that perchlorate is a low‐level background contaminant of raw and treated drinking water. Low concentrations (treated drinking water: <0.020–2.073 μg/L, mean 0.747 μg/L) were detected at every higher‐risk site. The concentrations were comparable in each of the four sampling exercises and no significant trends were apparent relating to the time of year, the type of risk or the method of chlorination. Limited data showed that removal by ion exchange and granular‐activated carbon may occur.     

Lead and cadmium contents in cereals and pulses in north-eastern China

It is known that, unlike Japanese, Koreans or southern Chinese who depend on rice as a major source of energy for daily life, people in north-eastern China rely not only on rice, but on wheat and other cereals and to a lesser extent also on pulses. Cereal and pulse samples were collected from open markets in north-eastern China, and analyzed by inductively-coupled plasma spectrometry (ICP-MS) for two potentially hazardous heavy metals — lead (Pb) and cadmium (Cd). The average Pb level in cereals (31.3 ng Pb/g as a geometric mean) and that of pulses (25.7 ng Pb/g) were similar to each other with no significant difference. Among the cereals, Pb contents were higher in foxtail millet (54.3 ng/g) and lower in maize (35.4 ng Pb/g; grain and flour in combination), wheat flour (28.8 ng Pb/g) and rice flour (22.7 ng Pb/g). Lead levels in two important types of pulses, kidney bean and soybean (24.6 and 30.8 ng Pb/g, respectively), were comparable to the levels in rice and wheat. In contrast, Cd levels were substantially higher in pulses (55.7 ng Cd/g) than in cereals (9.2 ng Cd/g), and among the pulses, Cd in soybean (55.7 ng Cd/g) was significantly higher than that in kidney bean (23.8 ng Cd/g). The possible public health implication of the Pb and Cd levels, especially the high Pb level in foxtail millet (54.3 ng Pb/g) and the high Cd level in soybean (73.5 ng Cd/g), is discussed.     

创新创业教育在高校实践教学中的研究与探索

大学生创新创业教育的开展对高校人才培养体系的完善具有非常重要的意义。针对目前我国高校创新创业教育模式的问题与不足进行探讨,分析研究了创新创业教育的实质,最后重点阐述了在实践教学中如何加强创新思路的引导,建立有效激励机制,开展创新及创业教育的应对策略,促进对大学生实践创新能力、创业就业能力和持续发展能力的培养。     

武汉城市景观文化生态保护建设的问题与对策

城市文化生态是形成城市特色的文化要素。历史古迹,优秀建筑,空间形态,环境特色,作为城市文化生态的显现部分,既是城市文化底蕴直观生动的反映,也是市民的情感港湾和精神家园。理应得到珍惜和保护。该文在系统地概括武汉景观文化生态特点的基础上,重点分析了当前武汉城市景观规划建设中的文化生态问题,提出了武汉今后改进城市景观文化生态规划建设的对策建议。