流化床O_2/CO_2燃烧(Ⅱ)-高氧浓度的中试研究

为给大型循环流化床O2/CO2燃烧系统在高氧气浓度下的燃烧提供参考,在燃烧室直径140 mm、高度6 000 mm的0.15 MW循环流化床燃烧试验系统上,在O2/N2气氛中,进行了煤在高氧浓度下的燃烧试验。实验结果表明,在一次风氧气浓度49.0%～53.3%、二次风氧气浓度50.8%～56.0%时仍可以安全、稳定燃烧。煤在燃烧过程中SO2收率为92.2%～94.0%,配风对SO2收率影响不大。不同风量配比下,NOx收率为6.71%～7.64%,N2O收率为5.13%～7.23%。降低一次风氧量,有助于降低NOx收率和N2O收率。推迟二次风加入时间,有助于降低N2O收率,但会使NOx收率升高。

高氧浓度恢复对HIIT训练后糖代谢影响

为探讨高强度间歇训练后于恢复期吸入高浓度氧气（90%O2）对于葡萄糖耐量、胰岛素敏感度、皮质醇浓度以及血糖浓度的影响。本研究选取40名大学男子足球队队员（年龄（21±3.3）岁,身高（177.9±3.9）cm,体重（72.5±5.9）kg）接受单次高强度间歇训练（high-intensity interval training,HIIT）,以120%-140%无氧阈值速度作为的运动强度,运动2 min,间隔休息1 min,重复7次,单次运动时间90 min,于HIIT后以高浓度氧气（90%O2）及常氧（21%O2）进行恢复90 min,于隔天交换恢复介入方式。运动前后分别对运动员进行口服葡萄糖给药,并测定给药后不同时间段的葡萄糖耐受度测试,以及分析血糖、胰岛素、皮质醇浓度。研究发现血糖值于运动后高氧恢复显著低于运动前与运动后常氧恢复,并达显著差异（p〈0.05）。胰岛素敏感度于运动前以及运动后高氧、常氧状态下恢复均未达显著差异（p〉0.05）。运动后高氧状态下恢复于第60 min、90 min之皮质醇浓度明显低于训练后常氧状态下恢复（p〈0.05）。所以单次HIIT后于高浓度氧气状态下恢复90 min,有助于减缓运动后生理压力和提升运动后肌肉细胞对葡萄糖吸收能力,是运动员进行训练时较为有效的一种运动模式。

城市污泥高固体浓度厌氧消化的研究进展

城市污泥的负面环境影响日益严重,已经成为我国最紧迫的环境问题之一。厌氧消化作为有效的污泥稳定化、减量化和能源回收技术,面临新的发展机遇,高固体浓度厌氧消化开始受到广泛关注。文章综述了高固体浓度污泥厌氧消化的概念、优势及研究现状,指出高固消化是今后污泥厌氧消化的发展趋势,而预处理强化的高固厌氧消化和与有机废物的共厌氧消化将是高固消化的主要发展趋势。

锐钛矿高氧空位浓度F′色心吸收光谱的第一性原理研究

采用基于密度泛函理论的平面波赝势方法计算了3种模型高氧空位浓度不同的锐钛矿晶体的吸收谱带,发现产生F′色心,而不能产生F色心;锐钛矿高氧空位范围内浓度越高,光能量吸收越强;浓度不同的高氧空位锐钛矿形成不同的吸收谱带;锐钛矿晶体的高氧空位浓度不同,F′色心引起的透射光不同,观察得到的颜色不同,和缺陷化学实验中得到的变化趋势相一致。

德尔格EVITA 4呼吸机氧浓度偏高报警故障分析及维修

本文着重介绍了呼吸机监测氧浓度部分出现的故障分析及解决办法,以供大家参考。

AAe高浓度高效率厌氧消化技术在有机废弃物处理行业的应用

本文详细介绍了AAe高浓度高效率厌氧消化技术(HHAR)的原理、技术优势以及与传统厌氧消化技术的对比,并以国内部分应用案例分析了高浓度高效率厌氧消化处理技术(HHAR)的环境效益、经济效益和社会效益。

动物高压氧舱机械结构设计

本文讲述了一款经济实用的高压氧舱的计算理论及设计过程,其用于研究在2个标准大气压下高氧浓度氧气对CO中毒治疗的效果。设计结合实际应用场地与应用条件对其结构定型,然后进行仿真模拟其受力情况确定材料,最后输出整个设备的完成结构与图纸。给我国在高压氧动物实验医疗研究上提供了一种稳定可靠的器材。

德尔格Evita系列呼吸机故障维修2例

1故障一故障现象:“氧浓度过高”报警。故障分析与排除:首先标定氧电池,标定通过,排除氧电池故障。进一步检查氧气红宝石阀是否漏气。用水路法确定静态下的红宝石阀不漏气。动态情况下,设置Vti为500,实测值Vte稳定在480左右,工作正常,排除红宝石阀故障。根据EVITA 4的标定原理,怀疑标定回路故障。断掉空气,用纯氧进行标定,可标定成功。接回空气后,再次标定,出现氧浓度过高故障。由此可以确定,标定回路混进空气.

高氧空位浓度对锐钛矿TiO_2莫特相变和光谱红移及电子寿命影响的第一性原理研究

基于密度泛函理论的第一性原理研究,通过对锐钛矿TiO2高氧空位浓度、态密度图及吸收光谱图的分析,发现锐钛矿TiO2高氧空位浓度的条件下,高氧空位浓度对禁带变窄、吸收光谱红移和电子寿命都有很大的影响,从理论上进一步解释了高氧空位浓度对禁带变窄的原因.同时,锐钛矿半导体在高氧空位浓度时发生莫特相变和锐钛矿氧空位在等离子体中吸收光谱红移实验进行比较,发现锐钛矿TiO2应适量控制高氧空位浓度对吸收光谱红移好于前者.适量控制高氧空位浓度的锐钛矿TiO2对制备高氧空位浓度的可见光光催化剂提供了可靠的数据.

The effect of exogenous sugar solution and high concentration of CO_2 on the contents of sugar and protein of Betula platyphylla leaves

The content of total sugar, sucrose, fructose and protein in the leaves of3-yr.-old Betula platyphylla was measured after the treatment by three exogenous sugar solutions(sucrose, fructose, glucose) and three high concentrations of CO_2 (700, 1 400, 2 100 μL/L·L^(-1))for about a month in 1998. The results showed that spraying three exogenous sugar solutionsincreased markedly the content of sugar and protein of leaves under 700 μL·L^(-1) and 1 400μL·L^(-1) CO_2 The effect of spraying exogenous sucrose solution was the best among the threeexogenous sugars. The treatment of spraying exogenous sugar solution and 2 100 μL·L^(-1) CO_2constrained the accumulation of total sugar and protein of leaves. There was no difference inprotein content of leaves when spraying glucose and fructose solutions under 700 μL·L^(-1) and 1400 μL·L^(-1) CO_2. The treatment of 2 100 μL·L^(-1) CO_2 concentration significantly increasedthe contents of total sugar, sucrose, fructose, and protein of leaves compared with that of the 700μL·L^(-1) and 1 400 μL·L^(-1) CO_2 except the plants spraying fructose solution. There waspositive correlation between the content of sugar of leaves and CO_2 concentration when sprayingsame exogenous sugar solution.

Response of seedlings of different tree species to elevated CO_2 in Changbai Mountain

Eco-physiological responses of seedlings of eight species, Pinus koraiensis, Picea koraiensis, Larix olgensis, Populus ussuriensis, Betula platyphylla, Tilia amurensis, Traxinus mandshurica and Acer mono from broadleaved/Korean pine forest, to elevated CO2 were studied by using open-top chambers under natural sunlight in Changbai Mountain, China in two growing seasons (1998-1999). Two concentrations of CO2 were designed: elevated CO2 (700 祄olmol-1) and ambient CO2 (400 祄olmol-1). The study results showed that the height growth of the tree seedlings grown at elevated CO2 increased by about 10%-40% compared to those grown at ambient CO2. And the water using efficiency of seedlings also followed the same tendency. However, the responses of seedlings in transpiration and chlorophyll content to elevated CO2 varied with tree species. The broad-leaf tree species were more sensitive to the elevated CO2 than conifer tree species. All seedlings showed a photosynthetic acclimation to long-term elevated CO2.

呼吸机维修实例

呼吸机是麻醉呼吸管理、呼吸衰竭治疗和危重症抢救不可或缺的重要医疗设备。Maque的Servo-i和Servo-s两种作为国内高端的呼吸平台,凭借着它简洁的用户界面,人性化的交互方式,全面的通气模式和直观的参数监测在我院得到了广泛的应用。我们在对病区ICU、急诊病区、新生儿等科室的16台Servo系列的呼吸机的日常维护和检修中发现几例典型的故障和解决方案，特报道如下：

Surface Ozone in Jiuzhaigou National Park, Eastern Rim of the Qinghai-Tibet Plateau, China

Located in southwestern China, Jiuzhaigou National Park is one of the most popular tourism destinations in China, famous for its unique aquatic ecosystems and beautiful forests. However, plants in the park may be at high ozone risk as a result of the intensive use of diesel tour buses in the park. In addition, Jiuzhaigou is close to a region with relatively high regional anthropogenic NOn emissions. During the growing season, also the peak season of tourism, we measured ozone concentration at two sites within the Park and these were： Jiuzhaigou Bureau （JB） and Long Lake （LL）. The results indicate that ozone concentrations were not high enough to cause foliar injury during the monitoring period, although the risk of ozone to plants was higher in spring than in summer and autumn. Diurnal ozone cycles at JB and LL displayed significantly higher ozone concentrations in the daytime than in the nighttime, suggesting photochemical production of ozone during the day and ozone deposition during the night as a result of the nocturnal boundary layer. In parallel with the seasonal change of background surface ozone in the Northern Hemisphere, maximum daily 8-h average ozone concentration （MDA8） and daily ozone concentration decreased from spring to autumn at the two sites. This temporal variation in Jiuzhaigou wasmost likely associated with the downward mixing of ozone-rich air from the free troposphere, because all the high-ozone events （MDA8 〉 70.0 ppb） were observed in spring and ozone-rich air from the free troposphere was the dominant cause. In summary, our data suggest that ozone concentrations in Jiuzhaigou were more affected by the regional-scale of background pattern in air quality and meteorological conditions than by local tourist activities.

pH Value Effects in Shear Rheology of Concentrated Alumina Suspensions

The influence of pH on the rheological properties of concentrated alumina suspensions was investigated. At various pH values, the alumina exhibited pseudoplastic, near Bingham flow behaviors. The fully-deflocculated suspensions exhibited Newtonian flow behaviors, while the fully-flocculated suspensions demonstrated very high viscosity and shear yield stress.

Problems associated with glucose toxicity:Role of hyperglycemia-induced oxidative stress

Glucose homeostasis deficiency leads to a chronic increase in blood glucose concentration. In contrast to physiological glucose concentration, chronic super-physiological glucose concentration negatively affects a large number of organs and tissues. Glucose toxicity means a decrease in insulin secretion and an increase in insulin resistance due to chronic hyperglycemia. It is now generally accepted that glucose toxicity is involved in the worsening of diabetes by affecting the secretion of B-cells. Several mechanisms have been proposed to explain the adverse effects of hyperglycemia. It was found that persistent hyperglycemia caused the functional decline of neutrophils. Infection is thus the main problem resulting from glucose toxicity in the acute phase. In other words, continued hyperglycemia is a life-threatening risk factor, not only in the chronic but also the acute phase, and it becomes a risk factor for infection, particularly in the perioperative period.

The preparation of high performance carbon electrode in electrochemical oxygen generator

The electrochemical oxygen generator has been popularized for its virtues, such as high oxygen concentration output, electricity saving, easy operation and maintenance. The key part of electrochemical oxygen generator is carbon electrode used as the cathode. The preparation of high performance carbon electrode was introduced in this paper. The properties of carbon electrode was tested. The electrochemical oxygen generator using carbon electrode as the cathode was prepared. The oxygen concentration and flow of this machine is hi,yher thnn ｜hal of others in china.

Decomposition and Products of Wheat and Rice Straw from a FACE Experiment Under Flooded Conditions

Winter wheat and rice straw produced under ambient and elevated CO2 in a China rice-wheat rotation free-air CO2 enrichment （FACE） experiment was mixed with a paddy soil at a rate of 10 g kg^-1 （air-dried）, and the mixture was incubated under flooded conditions at 25℃ to examine the differences in decomposition as well as the products of crop residues produced under elevated CO2. Results showed that the C/N ratio and the amount of soluble fraction in the amended rice straw grown under elevated CO2 （FR） were 9.8% and 73.1% greater, and the cellulose and lignin were 16.0% and 9.9% lesser than those of the amended rice straw grown under ambient CO2 （AR）, respectively. Compared with those of the AR treatment, the CO2-C and CH4-C emissions in the FR treatment for 25 d were increased by 7.9% and 25.0%, respectively; a higher ratio of CH4 to CO2 emissions induced by straw in the FR treatment was also observed. In contrast, in the treatments with winter wheat straw, the CO2-C and CH4-C emissions, the ratio of straw-induced CH4 to CO2 emissions, and the straw composition were not significantly affected by elevated CO2, except for an 8.0% decrease in total N and a 9.7% increase in C/N ratio in the wheat straw grown under elevated CO2. Correlation analysis showed that the net CO2-C and CH4-C emission from straw and the ratio of straw-induced CH4 to CO2 emissions were all exponentially related to the amount of soluble fraction in the amended straw （P 〈0.05）. These indicated that under flooded conditions, the turnover and CH4 emission from crop straw incorporated into soil were dependent on the effect of elevated CO2 on straw composition, and varied with crop species. Incorporation of rice straw grown under elevated CO2 would stimulate CH4 emission from flooded rice fields, whereas winter wheat straw grown under elevated CO2 had no effect on CH4 emission.

Application of Stable Isotope Techniques in Studies of Carbon and Nitrogen Biogeochemical Cycles of Ecosystem

Stable isotope techniques have been proved useful as tools for studying the carbon (C) and nitrogen (N) biogeochemical cycles of ecosystem. This paper firstly introduced the basic principles and the distribution characteristics of stable isotope, then reviewed the recent advances and applications of stable isotope in the C and N biogeochemical cycles of ecosystem. By applying the 13 C natural abundance technique, ecologists are able to understand the photosynthetic path and CO 2 fixation of plants, the CO 2 exchange and C balance status of ecosystem, the composition, distribution and turnover of soil organic C and the sources of organic matter in food webs, while by using the 13 C labeled technique, the effects of elevated CO 2 on the C processes of ecosystem and the sources and fate of organic matter in ecosystem can be revealed in detail. Differently, by applying the 15 N natural abundance technique, ecologists are able to analyze the biological N 2 -fixation, the N sources of ecosystem, the N transformation processes of ecosystem and the N trophic status in food webs, while by using the 15 N labeled technique, the sources, transformation and fate of N in ecosystem and the effects of N input on the ecosystem can be investigated in depth. The applications of both C and N isotope natural abundance and labeled techniques, combined with the elemental, other isotope ( 34 S) and molecular biomarker information, will be more propitious to the investigation of C and N cycle mechanisms. Finally, this paper concluded the problems existed in current researches, and put forward the perspective of stable isotope techniques in the studies on C and N biogeochemical cycles of ecosystem in the future.

Urban Air Quality Assessment of Kathmandu by Passive Sampling Technique

This paper presents an assessment of air quality of the Kathmandu valley, capital city of Nepal. This is the largest urbanized area in the country of about 300 km2. In the last two decades an intensive development of demographic, traffic and industry growth in the region was observed which was reflected on the air quality degradation. In order to evaluate the urban air quality in Kathmandu, a field monitoring network for particle deposition, nitrogen dioxide （NO2） and sulphur dioxide （SO2） by passive sampling with high space resolution was implemented in co-operation with IVL-Sweden. The net work composed of 60 monitoring sites distributed in a grid of 1 × 1 km2 covering all over the main city and some rural valley. Monitoring were carried out for two seasons, rainy and dry as two campaign monitoring. The diffusive samplers were prepared and analyzed in IVL, Sweden. Good agreements in particle deposition between the two campaigns were observed. The particle deposition to the surrogate surface varied between 3 and 608 μg@cm2·monthl for the monitoring periods. The NOz concentrations on the other hand were quite similar in the two campaigns, and the SO2 concentrations were much lower in the first campaign compared to the second. The ranges of NO2 and SO2 concentrations were found to be from 5.6 to 52.6 μg/m3 and 0.6 to 23.4 μg·m-3 respectively. Arc Info/Arc map GIS 9.2 software was used for production of maps of spatial distribution of all the three parameters in the valley. Seasonal variation and traffic influence were also studied. Local meteorological effects in the distribution of pollutants were clearly observed and the NO2 concentrations were strictly related with traffic intensity.