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1.
The aim of this research was to determine the accelerating effects of microorganisms on the biodeterioration of stone under air pollution and continental-cold climatic region in Erzurum, Turkey. Studies have been carried out on specimens of the Rustempasa Bazaar, the Lalapasa Mosque, the Erzurum Castle Mosque, the Double Minarets-Madrasah, the Great Mosque and the Haji Mehmet Fountain aged from 441 to 823 years old. The results showed that vegetative and reproductive (generative) forms of the microorganisms could develop during the winter months when the night time average temperature was even -25 degrees C. Also the reproductive forms had developed and the whole stone surface was covered with a biofilm caused by the microorganisms. Silicon, aluminum, calcium, potassium, titanium, magnesium, zinc, sulfur, iron, sodium, and niobium were found in the stones of the historical buildings with varying amounts through the SEM-EDS analysis. Some of these elements could be used as an energy resource for the microorganisms together with the air pollutants such as sulfur dioxide, nitrogen oxides and particles on the stone surfaces. Of 21 isolates, 15 species from 6 bacterium genera and 5 species from 5 fungi genera plus 1 fungi genera were identified on the deteriorated stone surfaces even during the coldest months by microbial identification system (MIS) and these findings were tested by SEM investigations.  相似文献   

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3.
用热重分析法,在一定氮气(20 mL/min)条件下对昆明地区常见9种针叶树种叶的热失重过程进行研究。通过热失重率(TG)和失重速率(DTG)曲线分析,求取样品的着火温度与燃烬温度并计算燃烧特性指数,由一级反应过程和Coats-Redfern模型计算得出热解动力学参数。根据分析和计算结果对9种针叶树种叶的相关特征参数进行排序。  相似文献   

4.
The recent energy crisis and the environment impacts of building industry have led to the active promotion of principles of sustainable development in recent times. Minimization of energy usage is the key to improve sustainability where the actual impact is assessed on the basis of life cycle cost estimates. In this context, the performance of insulated roof slabs which can be used as an alternative to conventional light weight roofs, have been assessed in detail especially with respect to air conditioned buildings. It is shown that insulated roof slabs could have a desirable behaviour with respect to life cycle performance in addition to providing other benefits such as cyclone resistance and higher robustness to the building.  相似文献   

5.
Aerosol samples collected in the industrial area of Estarreja, Portugal, were used to assess the source classes responsible for the particulate levels observed in the local atmosphere. Principal Component Analysis was applied separately to the concentrations of aerosol constituents and meteorological variables to obtain the number of Principal Components and to verify the influence of weather conditions on ambient air quality. The technique led to the conclusion that soil and transport emissions represent important aerosol sources even in this industrial environment. The quantitative contribution of each source class was calculated using Multilinear Regression Analysis; 37% of the aerosol mass had a soil origin, 8% was from sea spray, 18% resulted from transport emissions and 24% contained ammonium salts. Twelve percent of total suspended particle (TSP) mass could not be explained by any of the six Principal Components retained. Ammonium salts and two other minor Principal Components seem to result mainly from industrial emissions. More specific information about the contribution of each particular source was not possible with this technique.  相似文献   

6.
《Planning》2022,(3)
为研究溶藻弧菌Vibrio alginolyticus HA2同步硝化反硝化过程中氮的代谢产物,分别用以铵态氮(NH_4+-N)、硝态氮(NO_3+-N)、硝态氮(NO_3--N)、亚硝态氮(NO_2--N)、亚硝态氮(NO_2--N)为氮源的培养基培养溶藻弧菌HA2 120 h,测定不同时间段菌液浓度,以及NH_4--N)为氮源的培养基培养溶藻弧菌HA2 120 h,测定不同时间段菌液浓度,以及NH_4+-N、NO_3+-N、NO_3--N、NO_2--N、NO_2--N、pH和发酵罐中气体(N_2、NO、N_2O)的含量,并且拟合菌株生长曲线。结果表明:溶藻弧菌对NH_4--N、pH和发酵罐中气体(N_2、NO、N_2O)的含量,并且拟合菌株生长曲线。结果表明:溶藻弧菌对NH_4+-N、NO_3+-N、NO_3--N、NO_2--N、NO_2--N降解率最高分别为99.97%、99.95%、36.87%;生长极限k值分别为4.769、5.477、5.567;培养基中的NH_4--N降解率最高分别为99.97%、99.95%、36.87%;生长极限k值分别为4.769、5.477、5.567;培养基中的NH_4+-N直接被氧化为NO_3+-N直接被氧化为NO_3--N;试验中均未检测出NO、N_2O气体,各培养基中N_2量均有上升趋势;各培养基中pH均有增加趋势。研究表明,溶藻弧菌HA2具有开发为高效、环保、安全的硝化反硝化细菌的研究价值。  相似文献   

7.
摘 要:采集长白山地区7种常见阔叶树种叶片、树皮,通过热重分析仪测定燃点、碳化阶段开始温度、热值和灰分等,应用TOPSIS 分析法对树种热稳定性进行评价。根据实验结果,参数化了叶片、树皮有机质燃烧过程数学模型,用来研究叶片和树皮2类有机质燃烧过程质量损失和释放热量,得出7个阔叶树种热稳定性排序,山杨、大青杨、水曲柳、紫椴、核桃楸、黄波罗、蒙古栎热稳定性依次减弱。长白山常见7个阔叶树种有机质燃烧过程中叶片燃烧释放的热量更具持续性、树皮燃烧强度大,2类预测模型有效解释了长白山地区常见阔叶树种热稳定性。在长白山地区低质低效林、防火林带改造过程中,可优选热稳定性强的树种进行森林更新,为制定长白山地区森林防火减灾对策和有关部门战略决策提供参考。  相似文献   

8.
《Planning》2022,(2)
以史氏鲟Acipenser schrenckii为试验对象,在基础日粮中添加不同水平的紫丁香叶粉,研究紫丁香叶对史氏鲟生长性能和免疫指标的影响。试验共分9组(对照组、AH组),AH组),AH组试验饲料中紫丁香叶粉的质量分数分别为1%、2%、3%、4%、5%、6%、8%、10%,对照组饲料中不添加。饲养试验共进行56 d。结果表明:与对照组相比,A组、B组史氏鲟的增重率、特定生长率和饵料系数无显著差异(P>0.05);与对照组相比,除C组和F组外,其它各试验组鱼血浆中总蛋白和球蛋白含量均显著(P<0.05)或极显著下降(P<0.01);H组鱼血浆中白蛋白显著下降(P<0.05),谷丙转氨酶(ALT)显著升高(P<0.05),谷草转氨酶(AST)差异不显著(P>0.05);各试验组鱼血浆中C3、C4含量均比对照组有所降低,除C组和F组外,其余各组鱼血浆中C3、C4的含量均显著下降(P<0.05)。这说明,饲料中不同水平的紫丁香叶粉对史氏鲟生长和免疫具有不同程度的抑制作用。  相似文献   

9.
室内空气计算参数对空调系统经济性的影响   总被引:14,自引:4,他引:14  
殷平 《暖通空调》2002,32(2):21-25
讨论了室内空气计算参数变化对不同建筑的空调系统经济性的影响。分析结果表明,在大多数情况下,降低室内相对湿度,空调系统的能耗均可下降;无论在哪种情况下,降低室内相对湿度,空调系统的一次投资都明显减少,而且降低幅度明显大于能耗的变化。同时,室内相对湿度的降低可以明显提高人体舒适感和室内空气品质。  相似文献   

10.
A comparative study of the capabilities of black poplar-tree (Populus nigra L.) bark as a biomonitor of atmospheric heavy-metal pollution is reported. Performance indicators (concentrations and enrichment factors) of heavy metal bioaccumulation of bark were compared to the corresponding indicators of epiphytic lichens Xanthoria parietina (L.) Th. Fr. and Physcia adscendens (Fr.) H. Oliver, collected simultaneously with bark samples within the Kiev urban-industrial conurbation. The concentrations of 40 minor and trace elements in the samples were measured by a combination of epithermal and instrumental neutron activation analysis (NAA) using a 10 MW nuclear research reactor WWR-M as the neutron source. Statistical analysis of the data was carried out using non-parametric tests. It was shown that for the majority of the elements determined a good correlation exists between their concentrations in bark and in the lichen species. The accumulation capability of the bark was found to be as effective as, and in some cases better, for both types of lichens. Based on the background levels and variations of the elemental concentration in black poplar-tree bark, threshold values for the enrichment factors were established. For a number of elements (As, Au, Ce, Co, Cr, Cu, La, Mn, Mo, Ni, Sb, Sm, Ti, Th, U, V, W) an interspecies calibration was performed. An optimized pre-irradiation treatment of the bark sample was employed which efficiently separated the most informative external layer from the deeper layers of the bark and thus minimized variations of the element concentrations. Results of this study support black poplar-tree bark as an alternative to epiphytic lichens for heavy metal air pollution monitoring in urban and industrial regions, where severe environmental conditions may result in scarcity or even lack of the indicator species.  相似文献   

11.
The benthic macrofauna of the Bay of Muggia and its evolution in time was analysed in order to assess the impact of man-made pollution in this port area. The north and NE zones are totally industrialised while the southern zone is mainly used for tourism and aquaculture. The most important anthropic impacts were stagnation and direct urban and industrial discharges, which operated until the beginning of the 1990s. Forty-four stations were sampled in 1981, 12 of which were monitored over time (1975, 1981 and 1994). From 172 taxa 11783 organisms were identified. Polychaetes were the richest group, followed by molluscs, crustaceans and echinoderms. The dominant species was Corbula gibba (39.5%) followed by Pectinaria koreni (9%). Uni- and multivariate analyses showed a declining pattern for the fauna along a gradient of environmental stress. The very high concentrations of heavy metals in the Bay's sediments, especially Pb, contrasted with the diversity and biological index values found, indicating that many species could survive these conditions. The enforcement of the Italian ecological laws regarding water pollution control benefited the local macrofauna and evidenced the resilience of the system. C. gibba constituted a good biological indicator of zones of high instability (especially sedimentary) and of intermediate levels of pollution.  相似文献   

12.
The ability of Tillandsia capillaris Ruiz and Pav. f. capillaris and Tillandsia permutata A. Cast. to accumulate heavy metals was evaluated in relation to potential atmospheric emission sources in Argentina. The sampling areas (n=38) were chosen in the province of Córdoba, located in the center of Argentina, and categorized according to land use, anthropogenic activities and/or distance to potential heavy metal emission sources. In each sampling site, pools of 40-50 individuals of each species were made from plants collected along the four cardinal directions. The concentrations of V, Mn, Fe, Co, Ni, Cu, Zn, Pb and Br of these samples were measured by Total Reflection X-Ray Fluorescence (TXRF) analysis with Synchrotron Radiation. Each species was submitted to a cluster analysis in order to discriminate different groups of heavy metals as tracers of natural or anthropogenic sources. A Contamination Factor (CF) was calculated using the concentrations of the elements in each sample compared to their concentrations in the control samples. Finally, the rank coefficients of correlation between the CFs and the categorical variables characteristic of each site (land use and anthropogenic load) were analyzed. A positive correlation was found for T. capillaris between the CFs of V, Mn, Co, Ni, Cu and Zn and the urban-industrial category, whereas the CF values for Zn and Pb were positively correlated with the road category. In T. permutata there was a positive correlation between the CF of Zn and the urban-industrial category and the CF of Pb with the road category. We therefore conclude that T. capillaris is a more efficient metal accumulator in passive biomonitoring studies.  相似文献   

13.
This article deals with both an experimental study and a numerical model of the thermal behaviour of a building whose roof is equipped with photovoltaic panels (PV panels). The aim of this study is to show the impact of the PV panels in terms of level of insulation or solar protection for the building. Contrary to existing models, the one presented here will allow us to determine both the temperature field of the building and the electric production of the PV array. Moreover, an experimental study has been conducted in La Reunion Island, where the climate is tropical and humid, with a strong solar radiation. In such conditions, it is important to minimise the thermal load through the roof of the building. The thermal model is integrated in a building simulation code and is able to predict the thermal impact of PV panels installed on buildings in several configurations and also their production of electricity. Basically, the PV panel is considered as a complex wall within which coupled heat transfer occurs. Conduction, convection and radiation heat transfer equations are solved simultaneously to simulate the global thermal behaviour of the building envelope including the PV panels; this is an approach we call ‘integrated modelling’ of PV panels. The experimental study is used to give elements of validation for the numerical model and a sensitivity analysis has been run to put in evidence the governing parameters. It has been shown that the radiative properties of the PV panel have a great impact on the temperature field of the tested building and the determination of these parameters has to be taken with care.  相似文献   

14.
In groups of six, 30 female subjects were exposed for 4.8 h in a low-polluting office to each of two conditions--the presence or absence of 3-month-old personal computers (PCs). These PCs were placed behind a screen so that they were not visible to the subjects. Throughout the exposure the outdoor air supply was maintained at 10 l/s per person. Under each of the two conditions the subjects performed simulated office work using old low-polluting PCs. They also evaluated the air quality and reported Sick Building Syndrome (SBS) symptoms. The PCs were found to be strong indoor pollution sources, even after they had been in service for 3 months. The sensory pollution load of each PC was 3.4 olf, more than three times the pollution of a standard person. The presence of PCs increased the percentage of people dissatisfied with the perceived air quality from 13 to 41% and increased by 9% the time required for text processing. Chemical analyses were performed to determine the pollutants emitted by the PCs. The most significant chemicals detected included phenol, toluene, 2-ethylhexanol, formaldehyde, and styrene. The identified compounds were, however, insufficient in concentration and kind to explain the observed adverse effects. This suggests that chemicals other than those detected, so-called 'stealth chemicals', may contribute to the negative effects. PRACTICAL IMPLICATIONS: PCs are an important, but hitherto overlooked, source of pollution indoors. They can decrease the perceived air quality, increase SBS symptoms and decrease office productivity. The ventilation rate in an office with a 3-month-old PC would need to be increased several times to achieve the same perceived air quality as in a low-polluting office with the PC absent. Pollution from PCs has an important negative impact on the air quality, not only in offices but also in many other spaces, including homes. PCs may have played a role in previously published studies on SBS and perceived air quality, where PCs were overlooked as a possible pollution source in the indoor environment. The fact that the chemicals identified in the office air and in the chamber experiments were insufficient to explain the adverse effects observed during human exposures illustrates the inadequacy of the analytical chemical methods commonly used in indoor air quality investigations. For certain chemicals the human senses are much more sensitive than the chemical methods routinely used in indoor air quality investigations. The adverse effects of PC-generated air pollutants could be reduced by modifications in the manufacturing process, increased ventilation, localized PC exhaust, or personalized ventilation systems.  相似文献   

15.
《Planning》2022,(2)
研究了许氏平鲉Sebastes schlegeli幼鱼养殖过程中投饵量(30、38、46、54、62、70、86、102、120、140、160、180、200、220、240 mg/d)对鱼体的增重及对水环境中悬浮物、化学需氧量(COD)、氨氮(NH4+-N)含量的影响。结果表明:幼鱼在生长过程中的最佳投饵量为160 mg/d,当投饵量小于160mg/d时,许氏平鲉的增长速度随投饵量的增加而增加;当投饵量大于160 mg/d时,再增加投饵量也并不能提高幼鱼的增长速度。投饵量对水体中固体悬浮物、COD、氨氮含量的影响与投饵量对幼鱼增重的影响的结果具有高度的一致性,存在投饵过量指示点(SZ)、COD污染指示点(CZ)、氨氮污染指示点(NZ)。当投饵量小于SZ、CZ、NZ时,悬浮物、COD、氨氮含量均随投饵量的增加而缓慢增加;当投饵量大于SZ、CZ、NZ时,悬浮物、COD、氨氮含量迅速增加。养殖水体中COD的自净符合一般水体COD的自净规律。根据试验结果建立了投饵量(T)与悬浮物含量(S)的模型为S=-18.86+1.082T-0.0069T2+0.0002T3,投饵量与COD的模型为COD=0.16+0.977T-0.055T2+0.00017T3,COD自净模型为C=113.4×exp(-0.68t)。  相似文献   

16.
《Planning》2022,(2):128-131
分析了采用变风量空调系统空调房间的特性,推导出变风量送风方式下空调房间的数学模型,利用Matlab软件中的Simulink工具箱建立了空调房间的仿真模型。并通过算例对所建模型进行仿真分析,结果证明,该模型能够充分反映实际变风量空调房间的特性。  相似文献   

17.
Aquatic plants take up, transform and sequester organic contaminants and may therefore be used in phytoremediation for the removal of pollutants from wastewaters. A better understanding of factors affecting the rate of contaminant uptake by aquatic plants is needed to improve engineered systems for removal of pollutants from wastewaters. This work focused on the influence of initial concentrations of pesticide and population density of plants on toxicity and uptake of the fungicide dimethomorph by two duckweed species. An increased sensitivity to dimethomorph was observed with increasing duckweed population density. Less light, due to crowding, may explain this higher sensitivity and reduced removal rate. A positive relationship was also found between toxicity or contaminant uptake and initial pesticide concentration with a maximal removal of 41 and 26 µg g− 1 fresh weight of dimethomorph (at 600 µg L− 1 of dimethomorph and an initial density of 0.10 g E-flask− 1) by Lemna minor and Spirodela polyrhiza, respectively. This research also indicated that these aquatic plants can efficiently eliminate organic contaminants and may ultimately serve as phytoremediation agents in the natural environment.  相似文献   

18.
We have assessed whether the combined exposure to arsenic (As) and fluoride (F) exerts a different effect than the exposure to As alone on the pattern of expression of apoptosis and inflammatory genes by immune cells. RNA was extracted from peripheral blood mononuclear cells from twenty individuals exposed or not to As or F or both. Then, cDNA was isolated, and the expression of 180 genes related to apoptosis and inflammation was tested by a cDNA array test. We found significant differences in the expression of 9 apoptosis and 15 inflammation genes in the three exposed groups compared to non-exposed individuals. In addition, subjects exposed to As or F or both showed different patterns of expression of at least 19 genes. Our data indicate that the combined exposure to As and F has a different effect on gene expression than the exposure to As or F alone.  相似文献   

19.
《Building and Environment》2004,39(2):153-164
This research aims to clarify the effects and indoor environmental characteristics of natural and mechanical hybrid air-conditioning systems in office buildings during intermediate seasons and to obtain design data. Natural and mechanical hybrid air conditioning is an air-conditioning system that utilizes natural ventilation and mechanical air-conditioning systems to improve the quality of the indoor thermal and air environment, and to reduce energy consumption. This report first categorizes the available natural ventilation conditions and estimates the amount of natural ventilation available in a model building. Furthermore, based on the concept of task-ambient air conditioning, after controlling the average temperature in the task zone to a target air conditioning temperature (26°C), changes in the outdoor temperature/humidity and the inflow rate, and the indoor environment and amount of cool heat input were studied with changes in the size of the natural vent using three-dimensional Computational Fluid Dynamics (CFD) analysis. The results of these studies indicated that natural ventilation at temperatures lower than the indoor temperature effectively covered the lower indoor task zone through negative buoyancy, which enabled energy-saving air conditioning in the task zone.  相似文献   

20.
Real‐time bioaerosol monitoring is possible with fluorescence based instruments. This study provides information on major factors that can affect the fluorescence properties of airborne fungal spores. Two fluorescence‐based bioaerosol detectors, BioScout, and ultraviolet aerodynamic particle sizer (UVAPS), were used to study fluorescent particle fractions (FPFs) of released spores of three fungal species (Aspergillus versicolor, Cladosporium cladosporioides, and Penicillium brevicompactum). Two culture media (agar and gypsum board), three ages of the culture (one week, one month, and four months), and three aerosolization air velocities (5, 15, and 27 m/s) were tested. The results showed that the FPF values for spores released from gypsum were typically lower than for those released from agar indicating that poor nutrient substrate produces spores with lower amounts of fluorescent compounds. The results also showed higher FPF values with lower air velocities in aerosolization. This indicates that easily released fully developed spores have more fluorescent compounds compared to forcibly extracted non‐matured spores. The FPFs typically were lower with older samples. The FPF results between the two instruments were similar, except with four‐month‐old samples. The results can be utilized in field measurements of fungal spores to estimate actual concentrations and compare different instruments with fluorescence‐based devices as well as in instrument calibration and testing in laboratory conditions.  相似文献   

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