Seasonal Frost Effects on the Soil–Foundation–Structure Interaction System

This paper presents the results of more than one year’s monitoring efforts and analysis of the effects of environmental variables on the dynamic properties of a selected bridge in Anchorage, Alaska. A seismic monitoring system was installed on the bridge to study these effects. The dynamic properties of the bridge have been identified from the recorded time histories which include ambient noises, traffic-induced vibrations, and small-magnitude earthquakes. Hourly air temperature data from nearby meteorological station during the period of study were collected to estimate the frozen soil depth for modeling purpose. A finite-element model and multiple-input autoregressive model were applied to study the effects of environmental variables on the dynamic properties. The results show that the environmental variables can significantly affect the dynamic properties by modifying the stiffness of the bridge system and the seasonal frost is found to have the dominating effects over air temperature on the bridge dynamic properties in cold regions. The results show that the models explain well the variation of dynamic properties with environmental variables.     

Hanford Environmental Dose Reconstruction Project--an overview

The Hanford Environmental Dose Reconstruction Project was initiated because of public interest in the historical releases of radioactive materials from the Hanford Site, located in southcentral Washington State. By 1986, over 38,000 pages of environmental monitoring documentation from the early years of Hanford operations had been released. Special committees reviewing the documents recommended initiation of the Hanford Environmental Dose Reconstruction Project, which began in October 1987, and is conducted by Battelle, Pacific Northwest Laboratories. The technical approach taken was to reconstruct releases of radioactive materials based on facility operating information; develop and/or adapt transport, pathway, and dose models and computer codes; reconstruct environmental, meteorological, and hydrological monitoring information; reconstruct demographic, agricultural, and lifestyle characteristics; apply statistical methods to all forms of uncertainty in the information, parameters, and models; and perform scientific investigations that were technically defensible. The geographic area for the study includes approximately 2 x 10(5) km2 (75,000 mi2) in eastern Washington, western Idaho, and northeastern Oregon (essentially the Mid-Columbia Basin of the Pacific Northwest). Three exposure pathways were considered: the atmosphere, the Columbia River, and ground water. the radionuclide of interest for atmospheric pathway doses was 131I. The median dose for the maximally exposed individual was approximately 2.3 Gy (230 rad) to the thyroid over the period from 1944 to 1972 with a 90% subjective confidence interval of 0.54 to 8.4 Gy (54 to 840 rad). The Columbia River was studied from Priest Rapids Dam, upstream of the Hanford Site, to the mouth of the river and nearby bays. Radionuclides of interest for river pathway doses were 24Na, 32P, 65Zn, 76As, and 239Np. The median dose from the river pathway for the maximally exposed individual was approximately 0.0015 Sv (0.15 rem) effective dose equivalent in the period of maximum exposure (1950-1970). Doses from the groundwater pathway were determined to be below levels of interest for the project.     

Particulate Matter from Stone Crushing Industry: Size Distribution and Health Effects

A cluster of 50 stone crushing units located at Pammal, in suburban Chennai, the capital of Tamil Nadu State, India, is a source of high levels of dust generation in the vicinity of the crushers and in the communities surrounding them. Ambient air quality network consisting of 26 sampling locations were operated to continuously monitor the total and respirable particulate matter concentrations (TSP and PM10). The daily average ambient concentrations of TSP and PM10 varied from 342 to 2,470 and 90 to 1,200?μg/m3, respectively, near the source, while the average concentrations varied from 86 to 257 and 39 to 138?μg/m3 in ambient air. The average PM2.5 concentration varied from 41 to 388?μg/m3 at the source, whereas the concentration varied from 17 to 48?μg/m3 in ambient air. Personal samplers were also employed to quantify the TSP and RPM in the work environment and they varied from 22.5 to 80.5 and 13.5 to 53.7?mg/m3, respectively. Both ambient concentrations and occupational exposure levels exceeded the Indian National Standards at most of the locations. Pulmonary function tests performed on workers showed that the average values of pulmonary function in these workers are significantly lower than the average values reported for normal South Indian healthy males.     

无人值守空压机站的远程控制工艺

介绍了马钢新区无人值守空压站的设备监控内容,重点说明设备安全操作运行的工艺条件和采取的安全联锁控制。     

A protective role for calcitonin gene-related peptide in water-immersion stress-induced gastric ulcers in rats

For over a century, Cincinnati, Ohio, has been at the center of the nation's efforts to control water pollution. Site and subject of PHS activities to understand, manage, and prevent pollution, Cincinnati now carries on this public health legacy as home to EPA's water pollution programs. From ante-bellum way station for primary care and the seat of early 20th century scientific contributions to vibrant center for the development of environmental health programs after World War II, the Queen City has truly provided a number of watershed developments in the history of public health.     

Arizona hazardous air pollutants monitoring program

In order to evaluate the existing risk to public health in Arizona related to hazardous air pollution, ambient air monitoring for selected hazardous air pollutants (HAPs) was carried out in 1994-1996 in several representative urban and rural areas of Arizona. A wide range of organic HAPs was monitored, requiring a variety of sampling and analysis methods. Stainless steel SUMMA canisters were used for collection of volatile hydrocarbons and halocarbons, which were analyzed by capillary gas chromatography with flame ionization and electron capture detection (GC-FID/ECD). Carbonyl compounds were collected using 2,4-dinitrophenylhydrazine-impregnated cartridges and analyzed by high performance liquid chromatography with ultraviolet detection. Semi-volatile and non-volatile polycyclic aromatic compounds were collected using a sampling train consisting of a filter followed by a PUF/XAD-4/PUF sandwich cartridge. Following extraction, samples were analyzed by capillary GC with mass spectrometric detection (GC-MS). Database software was developed for data processing and reporting functions. This paper describes the sampling strategy and the sampling and analysis methods employed in the monitoring program and presents a summary of all the results obtained during the duration of the sampling program.     

Atmospheric dispersion and deposition of 131I released from the Hanford Site

Approximately 2.6 x 10(4) TBq (700,000 Ci) of 131I were released to the air from reactor fuel processing plants on the Hanford Site in southcentral Washington State from December 1944 through December 1949. The Hanford Environmental Dose Reconstruction Project developed a suite of codes to estimate the doses that might have resulted from these releases. The Regional Atmospheric Transport Code for Hanford Emission Tracking (RATCHET) computer code is part of this suite. The RATCHET code implements a Lagrangian-trajectory, Gaussian-puff dispersion model that uses hourly meteorological and release rate data to estimate daily time-integrated air concentrations and surface contamination for use in dose estimates. In this model, iodine is treated as a mixture of three species (inorganic gases, organic gases, and particles). Model deposition parameters are functions of the mixture and meteorological conditions. A resistance model is used to calculate dry deposition velocities. Equilibrium between concentrations in the precipitation and the air near the ground is assumed in calculating wet deposition of gases, and irreversible washout of the particles is assumed. RATCHET explicitly treats the uncertainties in model parameters and meteorological conditions. Uncertainties in 131I release rates and partitioning among the nominal species are treated by varying model input. The results of 100 model runs for December 1944 through December 1949 indicate that monthly average air concentrations and deposition have uncertainties ranging from a factor of two near the center of the time-integrated plume to more than an order of magnitude near the edge. These results indicate that approximately 10% of the 131I released to the atmosphere decayed during transit in the study area, approximately 56% was deposited within the study area, and the remaining 34% was transported out of the study area while still in the air.     

DNA sequences identical to Pneumocystis carinii f. sp. carinii and Pneumocystis carinii f. sp. hominis in samples of air spora

Samples of ambient air collected with three different types of spore traps in a rural location were examined for the presence of Pneumocystis carinii by screening for P. carinii-specific DNA sequences by DNA amplification. Eleven spore trap samples were analyzed by nested PCR, using oligonucleotide primers designed for the gene encoding the mitochondrial large subunit rRNA of P. carinii f. sp. carinii and P. carinii f. sp. hominis. The samples were collected over a 3-year period during the months of May to September, with a range of sampling times from 9 to 240 h. One air sample from an animal facility housing P. carinii-infected rats was also examined. P. carinii-specific amplification products were obtained from samples from each of the spore traps. The amplification products from eight air samples were cloned and sequenced. The majority of the recombinants from each of these samples had sequences identical to those of P. carinii f. sp. carinii and P. carinii f. sp. hominis, and a number of clones had single-base differences. These data suggest that sequences identical to those of P. carinii f. sp. carinii and P. carinii f. sp. hominis can be detected in samples of air collected in a rural location and that P. carinii may be a component of the air spora of rural Oxfordshire.     

变频节能技术在地铁车站通风空调系统应用

地铁车站空调通风系统是地铁车站设备的耗能大户,其耗电量约占地铁车站设备总用电量的50％左右。空调通风设备的选型是根据车站最大负荷确定的,而绝大多数时间空调通风设备均在选型负荷60％的情况下运行。因此采用比较经济合理的通风空调设备能更好的节约能源。     

Consumed creep life fraction assessment of critical locations of an in-service super heater outlet header under surveillance programme

Boilers and turbines including high-energy piping and headers are operated round-the-clock in the creep regime. For the integrity of such components and equipments, it is essential to have a real-time monitoring system to identify and monitor the critical locations. As per statutory requirement of IBR Act 391A of 1998, a component is to be taken for surveillance programme, if its design life is exhausted. One such exercise was conducted at locations in close proximity to the header-stub weld joints of higher heat-flux zone after 1,12,547 hours of operation. The in-situ metallography technique developed indigenously within the country (i.e., cryogenic in-situ metallography) was adopted for assessment of locations closest to the identified weld joints of a superheater outlet header (SHOH) of a 210 MW unit of a super thermal power station. The qualitative assessment done using high resolution microscopy has indicated that the creep cavities correspond to stage-II of Neubauer’s classification diagram. Subsequently image analysis of in-situ replicated photomicrographs extracted from the investigating locations was carried out. The accrued creep damages (cavitation) at the locations were quantified for cavitated grain boundaries and correspondingly ldA” parameters were derived to evaluate the extent of life exhaustion of respective locations.     

Removal of Indoor Airborne Bacteria by Nano-Ag/TiO2 as Photocatalyst: Feasibility Study in Museum and Nursing Institutions

Deterioration of indoor air quality attributable to airborne bacterial consortia is a widespread environmental problem. The main objective of this study is to evaluate the feasibility of applying the syngetic effect of nano-Ag/TiO2 as a photocatalyst and UV light to enhance the disinfecting capability of full-scale bacterial restraining equipment on-site in the National Museum of Natural Science and a medical-nursing institute. The influence of initial counts of total airborne bacteria and volume of space on the efficiency of bacterial restraining have been studied. In the case of museum application, a higher initial total bacterial count leads to better bacterial restraining rates; Site A (initial total bacterial counts = 506??CFU/m3) has the best bacterial restraining rate (92%) as compared with Site B (69%, initial total bacterial counts = 158??CFU/m3) and Site C (80%, initial total bacterial counts = 338??CFU/m3) after 24 h of operation. Higher initial counts of total airborne bacteria lead to an increasing bacterial restraining rate. Approximately 92% (Site A) and 74% of restrained bacterial rate were observed in a museum and nursing institutions, respectively, under the similar initial total airborne bacterial counts (506, 598??CFU/m3). The results illustrate that changes in the volume of space do not have significant inhibitory effects on the efficiency. The proposed equipment can disinfect air to restrain bacteria effectively, as demonstrated on-site in museums and nursing institutions; the results will be valuable references for designing a full-scale commercialized device for large-scale applications in the future.     

Diagnosis of disseminated intravascular coagulation

The variations of the measured dose rate in air should be recognized especially where background radiation is used as a comparative benchmark to assess radiation surveillance and environmental remediation work. In this note, the natural variations of the combined gamma and cosmic-ray background air-dose rate as measured by lithium fluoride thermoluminescence dosimeters are reported. The dosimeters were deployed monthly at locations within 150 km of the Environmental Measurements Laboratory in New York City. Urban and suburban stations were established with simultaneous indoor and outdoor measurements at some locations. Measurements were obtained over 10 to 18 years. The mean air-dose rates from the six outdoor and four indoor stations vary from 50.8 to 123.1 nGy h(-1). The range of the annual dose rates expressed as a percent-difference of the minimum and maximum is 5.3 to 18.0%. Commonly, 1-mo deviations from the long term mean of about +/-10 to +/-25% are observed. An abrupt decrease in the annual dose rate at one of the measurement sites was attributed to a minor relocation of a dosimeter. Structural shielding factors for the first and second floors of a residence are reported. The ground level location of a dosimeter inside another residence apparently resulted in a very high shielding factor. Finally, a gradual decrease of the dose rate at most of the stations is shown to exist (approximately -0.3 nGy h(-1) y(-1) for the outdoor stations). Plausible causes of this trend are briefly discussed.     

Correlation for Diffuse Radiation from Global Solar Radiation and Sunshine Data at Beijing, China

Solar radiation data are essential for the work of energy planners, engineers, and agricultural scientists. However, most solar radiation recording stations measure only global radiation in China. It is, therefore, necessary to elaborate correlations between the rarely available diffuse radiation and other climatic data. In the present study, 10-year data (1995–2004) of daily global diffuse solar radiation and sunshine duration obtained at Beijing meteorological station of China was analyzed to guide future projects. Nine models correlating the diffuse fraction (Kd) with both the clearness index (Kt) and percentage possible sunshine (S/S0) and each variable separately were tested. The accuracy of the correlations is performed in terms of the two widely used statistical indicators, mean bias error, and root mean square error. The results indicate that the correlations relating Kd with both Kt and S/S0 are more reliable than using each variable separately and Model 9 is preferred for its accuracy. The recorded data of Zhengzhou meteorological station are compared with the corresponding values predicted by Model 9 of Beijing. Model 9 provides predictions very close to the measured values of Zhengzhou. Therefore, it may be concluded that Model 9 can be used for estimating diffuse solar radiation for locations of semiwet region of the north of China where only global solar radiation and sunshine duration are available.     

An investigation of indoor air contamination in residences above dry cleaners

An investigation of residences located above dry cleaning facilities was conducted to determine whether indoor and outdoor air concentrations of the dry cleaning solvent tetrachloroethene (perchloroethylene, PCE) were elevated compared to residences not near a dry cleaning facility. Data were also collected on the dry cleaners' operating conditions and equipment. Significantly elevated levels of PCE were found in the indoor air of each of six apartments located above dry cleaners compared to control residences for both day and night samples. The PCE concentrations in outdoor air near the dry cleaners were also significantly elevated compared to control locations and were lower than the concentrations measured indoors. The type of dry cleaning machine was significantly associated with the concentration of PCE found in the apartment above. A strong correlation was also found between the day and night PCE levels in the study apartments.     

The sea to air bacteria transfer from the coastal waters

Bacteria transfer from the water into the air may play an important role in bioaerosol cycle. Bubbles raising through the water column collect bacteria but also other suspended material and transport them towards water surface. When the bubble burst at the water surface collected material are skimmed off the bubble to become highly enriched in jet and film drops. After ejection airborne droplets can evaporate and as small droplets can be transported even to remote locations. Such a stream of aerosol droplets may carry stream of bacteria scavenged from the water column. The fate of bacteria in the air may possibly depend on the environmental conditions like intensity of sunlight or ambient air humidity. In addition the wind speed might be responsible for both wave/bubble mediated production of marine originated droplets and their transport in the atmosphere. The evidences that bacteria are transferred from the breaking waves, in particular in the coastal zone, were observed during several field experiments conducted in 1994 and 1995 over the Gulf of Gdansk and the Baltic Sea coast. Enhanced sea to air bacteria transfer were noticed over the polluted waters where in addition gas supersaturations in the water were recorded. Further laboratory investigations of bacteria scavenge via bubbles produced by single capillary and by plume of bubbles produced by ceramic stone indicated high enrichment within both mesophile and psychrophile bacteria categories.     

New autosomal recessive syndrome of severe microcephaly and skeletal anomalies including posterior rib-gap defects

A simultaneous comparison of human exposure to solar ultraviolet radiation at two locations was performed to study the effect of environmental factors and human attitudes on personal ultraviolet exposure. The study took place on 29 October 1996 in Toowoomba (27.5 degrees S, 151.9 degrees E) and Brisbane (27.4 degrees S, 153.1 degrees E), Queensland, Australia. From the data collected by calibrated ambient ultraviolet monitoring stations located in Toowoomba and Brisbane, Toowoomba received 68% more UVA (320-400 nm) and 61% more UVB (280-320 nm) than Brisbane from 07:00 to 10:00 Australian Eastern Standard Time (EST). From 10:00 to 17:00 EST Toowoomba received 5% more UVA and 20% less UVB than Brisbane. High ambient ultraviolet levels recorded by ultraviolet stations were reinforced by measurement of the personal ultraviolet exposure of human subjects wearing polysulfone dosimeters. Contrary to the common belief that the ultraviolet exposure to the human body is higher near the beach (i.e., coastal areas) than the inland area, the average erythemal weighted ultraviolet exposure on the chest and shoulder of each subject in the inland city of Toowoomba (127 km to the west of Brisbane) was 30% higher than in the coastal city of Brisbane from 07:00 to 17:00 EST. Evidence is also presented to suggest a relationship between altitude, climatic conditions, the human attitude, and the level of personal exposure to ultraviolet radiation.     

Assessment of dialysis adequacy using the dialysate urea monitor: preliminary experience of the dialysate urea monitor

Numerous studies have identified a strong linkage between the delivered dialysis dose (Kt/V) and the survival of hemodialysis (HD) patients. However, the current method used to calculate Kt/V requires multiple blood samples and the process is complex and time consuming. We evaluate the performance of a recently developed on-line monitor (Biostat 1000 dialysate urea monitor, Baxter) that measures the urea concentration in the effluent dialysate and displays Kt/V and nPCR immediately after hemodialysis. To verify the performance of the urea monitor, we selected 21 hemodialysis patients, calculated their Kt/V and nPCR values from blood samples obtained during each hemodialysis, and compared the results with data obtained using the urea monitor. The Kt/V and nPCR values calculated by the urea monitor were both significantly correlated with those obtained using blood samples (R = 0.804, p < 0.001 in Kt/V and R = 0.749, p < 0.001 in nPCR). Our results suggest that the urea monitor may be used for on-line assessment of dialysis adequacy and obviates the need for blood sampling.     

Evaluating the Sensitivity of Attic Radiant Barrier Performance to Climate Parameters

By employing a calibrated and tested computer model, simulations of ceiling heat transfer in typical residential attics located in 12 locations across the United States were obtained to study the sensitivity of attic radiant barrier performance to local climate parameters. For each location, the net ceiling heat flux over the summer cooling season was computed for an attic with and for an attic without an installed radiant barrier. The net reduction of heat flux induced by the radiant barrier was computed and then related to climate variables. Among the local environmental parameters, the local ambient air temperature, local ambient humidity, and latitude had significant effects on the performance of radiant barriers. It was concluded that the installation of radiant barriers would be most beneficial in regions with high outdoor air temperatures and high relative humidity.     

Pulmonary rehabilitation and self-care after ambulatory surgery

OBJECTIVES: To identify risk factors for dental fluorosis that cannot be explained by drinking water fluoride concentration alone. METHODS: Two hundred eighty-four Tanzanian children ages 9 to 19 (mean 14.0+/-SD 1.69), who were lifetime residents at differing altitudes (Chanika, 100 m; Rundugai, 840 m; and Kibosho, 1,463 m; Sites 1, 2, and 3 respectively) were examined for dental fluorosis and caries. They were interviewed about their food habits, environmental characteristics and use of a fluoride-containing food tenderizer known locally as magadi. Meal, urine, water and magadi samples supplied by the participants were analyzed for fluoride content. Urine samples were also analyzed for creatinine concentration. Four magadi samples from Sites 1 and 3 were analyzed for complete element composition. RESULTS: Of the 13 water samples from Site 2, 10 contained > or =4 mg/L F, ranging from 1.26 to 12.36 mg/L with a mean+/-SD of 5.72+/-4.71 mg/L. Sites 1 and 3 had negligible water fluoride of 0.05+/-0.05 and 0.18+/-0.32 mg/L respectively. Mean TFI fluorosis scores (range 0-9) for Site 2 were high: 4.44+/-1.68. In Sites 1 and 3, which both had negligible water fluoride, fluorosis scores varied dramatically: Site 1 mean maximum TFI was 0.01+/-0.07 and Site 3 TFI was 4.39+/-1.52. Mean DMFS was 1.39+/-2.45, 0.15+/-0.73 and 0.19+/-0.61 at Sites 1, 2, and 3, respectively. There were no restorations present. Urinary fluoride values were 0.52+/-0.70, 4.34+/-7.62, and 1.43+/-1.80 mg/L F at Sites 1, 2, and 3, respectively. Mean urinary fluoride values at Site 3 were within the normal urinary fluoride reference value range in spite of pervasive severe pitting fluorosis. Meal and magadi analyses revealed widely varied fluoride concentrations. Concentrations ranged from 0.01 to 22.04 mg/L F for meals and from 189 to 83211 mg/L F for magadi. Complete element analysis revealed the presence of aluminum, iron, magnesium, manganese, strontium and titanium in four magadi samples. There were much higher concentrations of these elements in samples from Site 3, which was at the highest altitude and had severe enamel disturbances in spite of negligible water fluoride concentration. An analysis of covariance model supported the research hypothesis that the three communities differed significantly in mean fluorosis scores (P<0.0001). Controlling for urinary fluoride concentration and urinary fluoride:urinary creatinine ratio, location appeared to significantly affect fluorosis severity. Urinary fluoride:urinary creatinine ratio had a stronger correlation than urinary fluoride concentration with mean TFI fluorosis scores (r=0.43 vs r= 0.25). CONCLUSIONS: The severity of enamel disturbances at Site 3 (1463 m) was not consistent with the low fluoride concentration in drinking water, and was more severe than would be expected from the subjects' normal urinary fluoride values. Location, fluoride in magadi, other elements found in magadi, and malnutrition are variables which may be contributing to the severity of dental enamel disturbances occurring in Site 3. Altitude was a variable which differentiated the locations.     

Biomonitoring of United States Army soldiers serving in Kuwait in 1991

Biomarkers of polycyclic aromatic hydrocarbon (PAH) exposure and genetic biomarkers of potential cancer susceptibility were determined in a group of United States Army soldiers who were deployed to Kuwait and Saudi Arabia in 1991 in the aftermath of the Persian Gulf War. Because hundreds of oil well fires were still burning, there was concern that ground troops stationed in Kuwait might be exposed to high levels of PAHs and other toxicants. The United States Army Environmental Hygiene Agency monitored air and soil for ambient PAHs. In addition, a group of 61 soldiers was involved in the biomonitoring study reported here. These soldiers kept diaries of daily activities and provided blood and urine samples in Germany (June) before deployment to Kuwait, after 8 weeks in Kuwait (August), and 1 month after the return to Germany (October). Here we present data for PAH-DNA adducts measured by immunoassay in blood cell DNA samples obtained at all three sampling times from 22 soldiers and bulky aromatic adducts measured by 32P-postlabeling in blood cell DNA samples from 20 of the same soldiers. Urinary 1-hydroxypyrene-glucuronide levels were determined by synchronous fluorescence spectrometry in a matched set of samples from 33 soldiers. Contrary to expectations, environmental monitoring showed low ambient PAH levels in the areas where these soldiers were working in Kuwait. For both DNA adduct assays, levels were the lowest in Kuwait in August and increased significantly after the soldiers returned to Germany (October). Urinary 1-hydroxypyrene-glucuronide levels were also lowest in Kuwait and highest in Germany, but the differences were not statistically significant. The PAH-exposure biomarker levels were not significantly influenced by polymorphic variations of CYP1A1 (MspI) and glutathione S-transferases M1 and T1. Overall, the data suggest that this group of soldiers was not exposed to elevated levels of PAHs while deployed in Kuwait.