On-site Sampling Research Articles

Characteristics of Particulate Matter Emissions from the Coking Process

To investigate the particulate matter emission characteristics of various emitting sources of the coking process of iron and steel plants, an automatic dust (smoke) tester and an eight-staged Anderson sampler were employed to conduct onsite sampling of particulate matter emissions from the coking process, including coal loading and coke pushing, coke dry quenching exhaust and coke screening and transferring in a steel plant, based on the measurement of particulate matter in the exhaust of fixed sources and sampling of gaseous pollutants. The morphology, particle size distribution, and chemical composition of the particulate matter from different sources were investigated. The results show that the single particles can be divided into five categories:iron-rich, silicon-rich, calcium-rich, carbon, and smoke polymer. They mainly appear in four forms:polygon block, irregular lamellae, lumps, and floc. The particle size of the coal loading and coke pushing unit mainly is 3.3-4.7 μm, while it is 3.3-4.7 μm and 5.8-9.0 μm for the dry quenching exhaust and 4.7-5.8 μm for the coke screening and transferring unit. The main chemical components of particulate matter in the coking process are C, SiO2, Al2O3, S, CaO, and TFe, with contents of 76.30%-81.30%, 5.36%-5.91%, 3.96%-4.26%, 1.15%-1.34%, 0.52%-1.59%, and 0.81%-1.34%, respectively.

Behavior and fate of As, Se, and Cd in an ultra-low emission coal-fired power plant

Environmental concerns regarding the toxicity of trace elements (TEs) and the harmful effects of these elements on humans have attracted worldwide attention. To meet stricter environmental policies, some coal-fired power plants have installed ultra-low emission equipment. In this paper, the behavior and fate of the trace elements As, Se, and Cd originating in an ultra-low emission coal-fired power plant equipped with air pollution control devices (APCDs), including selective catalytic reduction (SCR) equipment, a low-temperature economizer (LTE), an electrostatic precipitator (ESP), a wet flue gas desulfurization (WFGD) system, and a wet electrostatic precipitator (WESP), were investigated. Onsite samples of the feed coal, bottom ash, fly ash, gypsum, desulfurization slurry, WFGD effluent, WFGD-treated water, and WESP effluent were systematically collected and analyzed. The SCR and LTE configurations achieved a partial removal of As, Se, and Cd. The ESP trapped virtually all the particles and had a synergistic effect on the removal of the TEs. A systematic study of the recycling of the desulfurization slurry revealed TE enrichment in the WFGD system; because it concentrated in the liquid fraction of the gypsum slurry, Se was particularly susceptible to this enrichment. The effluent water treatment system achieved TE removal with efficiencies exceeding 94%. WESP operation achieved extensive removal of TE-enriched particles with percentages greater than 90%. The overall efficiencies of As, Se, and Cd removal obtained by the APCD system as a whole were 95.94%, 98.22%, and 92.70%, respectively.

Portable Analyzer for On-Site Determination of Dissolved Organic Carbon-Development and Field Testing.

Dissolved organic carbon (DOC) is a sum parameter that is frequently used in water analytics. Highly resolved and accurate DOC data are necessary, for instance, for water quality monitoring and for the evaluation of the efficiency of treatment processes. The conventional DOC determination methods consist of on-site sampling and subsequent analysis in a stationary device in a laboratory. However, especially in regions where no or only poorly equipped laboratories are available, this method bears the risk of getting erroneous results. For this reason, the objective of the present study was to set up a reliable and portable DOC analyzer for on-site analysis. The presented DOC system is equipped with an electrolysis-based decomposition cell with boron-doped diamond electrodes (BDD) that oxidizes the organic compounds to carbon dioxide. Within this study, the influence of different electrode materials and the composition of the applied electrolytes on the DOC decomposition in an undivided electrolytic cell were systematically investigated. Furthermore, some technical aspects of the portable prototype are discussed. After a detailed validation, the prototype was used in an ongoing monitoring program in Northern India. The limit of detection is 0.1 mg L−1 C with a relative standard deviation of 2.3% in a linear range up to 1000 mg L C−1. The key features of the portable DOC analyzer are: No need for ultra-pure gases, catalysts or burning technology, an analyzing time per sample below 5 min, and a reliable on-site DOC determination.

Application of Satellite Remote Sensing Technology to Monitor Rice Planting Area in Fujian Province

This study will focus on the specific physiological characteristics of rice at different stages of growth and development, the environmental background features and the spectral features it exhibits at each waveband, and compare the differences between its spectral characteristics and other features, selecting multiple periods. The satellite data, using a certain extraction method, separate early rice, middle rice and late rice to achieve early rice, mid-season and late rice planting area information extraction, and then compare the extraction results with on-site sampling survey results to comprehensively evaluate the use of MODIS multi-phase satellites. Comprehensive evaluation of matching effects is be done using MODIS multi-temporal satellite data to extract rice planting area information and spatial location.

Changes in the properties of conventional crude oil before and after CO2 flooding

In order to enhance oil recovery of a conventional oil reservoir by CO2 flooding, the changes in the properties of the crude oil before and after CO2 flooding are systematically investigated by on-site sampling and experimental testing. The results show that, after CO2 flooding, the light hydrocarbons of the produced crude oil is increased and the heavy hydrocarbons of the produced crude oil is decreased due to the deposition of resins and asphaltenes in the pores of the formation. In addition, the produced fluid (a mixture of oil and water) has a high water separation rate, the oil- water interface has a high tension value, and the crude oil has a high acid value and a low viscosity. The conclusions can provide a certain guidance for high-efficiency development of a conventional oil reservoir by CO2 flooding.

Gasoline Handling Automatic Sampling Detection Device Based on Gas Chromatography

This article has designed a vehicle gasoline on-site sampling and rapid detection device. Automatically taking gasoline samples during gasoline handling, two-dimensional gas chromatographic method is used for the rapid quantitative detection of the unconventional additive methylal. The heavy components are separated by back-blowing to air with the non-polar capillary column while the methylal and light components are separated by a polar column to determine the methylal content. The experiment shows that linear relationship between value of peaks area and mass concentration of methylal is keep in the range of 0.020∼90.0mg/mL with the correlation coefficients of 0.99, and the relative standard deviation (RSD) are less than 2%. The study shows that the limits of detection are 0.012g/L. This device can provide effective means for vehicle gasoline on-site sampling and quality control.

Correcting On-Site Sampling Bias: A New Method with Application to Recreation Demand Analysis

Collecting data via on-site surveys is convenient and can be cost-effective. However, the on-site sampling scheme over-samples frequent site visitors and omits nonvisitors, which can result in biased and inconsistent estimation of population parameters. A common empirical approach to addressing the sampling issues is to make adjustments directly to the assumed population distribution. We propose an alternative empirical strategy that utilizes the sample distribution and treats endogenous stratification and truncation separately. Monte Carlo simulation shows this proposed empirical strategy has merit. A case study of recreation demand for coastal beaches using on-site survey data is presented.

Thermographic cameras reveal high levels of crepuscular and nocturnal shore-based recreational fishing effort in an Australian estuary

Abstract Although recreational fishing at night is a popular activity, crepuscular and nocturnal fishing effort and catches are often unaccounted for in fisheries assessments. Here, we present a method for estimating 24-h shore-based recreational fishing effort involving the analysis of data from dual-lens thermographic cameras. Cameras were installed at three sites along the foreshore in Peel-Harvey Estuary, a Ramsar Wetland in Western Australia. Stratified random sampling was used to select days for image analysis between March 2015 and February 2016 and examination of images enabled fishing effort to be calculated for the 12-month period. Crepuscular recreational fishing effort at the three sites ranged between 4.5% and 11.3% and nocturnal recreational fishing effort ranged between 6.1% and 26.9% of total recreational fishing effort. Crepuscular and nocturnal recreational fishing were more prevalent between November and March and occurred on both weekdays and weekend days. The majority of recreational fishers identified from the day-time images (96.5%) were targeting blue swimmer crabs (Portunus armatus) using scoop nets. Multiple lines of evidence suggest that most crepuscular and nocturnal activity involved the same method of fishing. The results demonstrate that restricting onsite recreational fishing surveys to daylight hours can lead to large underestimates of total fishing effort and total recreational catches within a fishery. Our method can easily be applied to other fisheries to justify the inclusion of night-time onsite sampling and to design cost-effective sampling strategies.

Polymeric ionic liquid-based portable tip microextraction device for on-site sample preparation of water samples

On-site sample preparation is highly desired because it avoids the transportation of large-volume samples and ensures the accuracy of the analytical results. In this work, a portable prototype of tip microextraction device (TMD) was designed and developed for on-site sample pretreatment. The assembly procedure of TMD is quite simple. Firstly, polymeric ionic liquid (PIL)-based adsorbent was in-situ prepared in a pipette tip. After that, the tip was connected with a syringe which was driven by a bidirectional motor. The flow rates in adsorption and desorption steps were controlled accurately by the motor. To evaluate the practicability of the developed device, the TMD was used to on-site sample preparation of waters and combined with high-performance liquid chromatography with diode array detection to measure trace estrogens in water samples. Under the most favorable conditions, the limits of detection (LODs, S/N = 3) for the target analytes were in the range of 4.9–22 ng/L, with good coefficients of determination. Confirmatory study well evidences that the extraction performance of TMD is comparable to that of the traditional laboratory solid-phase extraction process, but the proposed TMD is more simple and convenient. At the same time, the TMD avoids complicated sampling and transferring steps of large-volume water samples.

Copper Speciation for Natural Water by On-site Sample Treatment/Solid-phase Extraction/Inductively Coupled Plasma Mass Spectrometry.

Herein, we determined the contents of Cu(I), Cu(II), and hydrophobic Cu in natural water using on-site sample treatment, solid-phase extraction (SPE), and inductively coupled plasma mass spectrometry (ICP-MS) analysis. To prevent Cu species changes in the sampling, filtering and preconditioning steps were performed in a closed system using plastic syringes and a disposable membrane filter. Bathocuproin disulfonate (BCS) and ethylenediaminetetraacetic acid (EDTA) were selected as a Cu(I)-selective complexing agent and a Cu(II) masking agent, respectively, whereas ascorbic acid (AA) was used to reduce Cu(II) to Cu(I). Pre-conditioned samples were passed through a hydrophobic SPE column, and the retained Cu species were eluted with ethanol. Subsequently, the eluate was concentrated, and the residue was re-dissolved in 2 M HNO3 and subjected to ICP-MS analysis. No artificial changes of Cu(I) and Cu(II) species were observed at any time, with the analytical detection limit of total Cu and the blank value equaling 0.0008 and 0.0025 μg kg-1, respectively. The developed method was applied to real estuarine, riverine, and seawater samples collected in Tokushima prefecture, Japan.

Bringing Packed Red Blood Cells to the Point of Combat Injury: Are We There Yet?

ObjectiveHemorrhage is the leading cause of injury-related prehospital mortality. We investigated worst-case scenarios and possible requirements of the Turkish military. As we plan to use blood resources during casualty transport, the impact of transport-related mechanical stress on packed red blood cells (PRBCs) was analyzed.Materials and MethodsThe in vitro experiment was performed in the environmental test laboratories of ASELSAN®. Operational vibrations of potential casualty transport mediums such as Sikorsky helicopters, Kirpi® armored vehicles, and the NATO vibration standard MIL-STD-810G software program were recorded. The most powerful mechanical stress, which was created by the NATO standard, was applied to 15 units of fresh (≤7 days) and 10 units of old (>7 days) PRBCs in a blood cooler box. The vibrations were simulated with a TDS v895 Medium-Force Shaker Device. On-site blood samples were analyzed at 0, 6, and 24 h for biochemical and biomechanical analyses.ResultsThe mean (±standard deviation) age of fresh and old PRBCs was 4.9±2.2 and 32.8±11.8 days, respectively. Six-hour mechanical damage of fresh PRBCs was demonstrated by increased erythrocyte fragmentation rates (p=0.015), hemolysis rates (p=0.003), and supernatant potassium levels (p=0.003) and decreased hematocrit levels (p=0.015). Old PRBC hemolysis rates (p=0.015), supernatant potassium levels (p=0.015), and supernatant hemoglobin (p=0.015) were increased and hematocrit levels were decreased (p=0.015) within 6 h. Two (13%) units of fresh PRBCs and none of the old PRBCs were eligible for transfusion after 6 h of mechanical stress.ConclusionWhen an austere combat environment was simulated for 24 h, fresh and old PRBC hemolysis rates were above the quality criteria. Currently, the technology to overcome this mechanical damage does not seem to exist. In light of the above data, a new national project is being performed.

Electrified Soft Interface as a Selective Sensor for Cocaine Detection in Street Samples.

A straightforward, direct, and selective method is presented for electrochemical cocaine identification in street samples. The sensing mechanism is based on a simple ion transfer reaction across the polarized liquid–liquid interface. The interfacial behavior of a number of cutting agents is also reported. Interfacial miniaturization has led to improved electroanalytical properties of the liquid–liquid interface based sensor as compared with the macroscopic analogue. The reported method holds great potential to replace colorimetric tests with poor selectivity for on-site street sample analysis.

Study of the High Temperature Metallurgical Properties of On-Site Samples with Vanadium–Titanium Magnetite

In China, two typical vanadium–titanium magnetite ores were used as raw materials in iron making. In order to obtain the differences in the high temperature metallurgical properties of these ores, the phase and microstructure of on-site sinter, pellet, slag and laboratorial non-dripped slag were analyzed by XRD and SEM–EDS. The results show that the phases of two typical sinter and pellet have no significant changes, but the microstructures are different. The softening start temperature and softening zone of high chromium vanadium–titanium magnetite (HCVTM) burden are higher than ordinary vanadium–titanium magnetite (VTM) burden. The melting start temperature of HCVTM burden is higher and melting–dripping zone is smaller than VTM burden, which is beneficial to the blast furnace smelting. In addition, the calculation results using Factsage 7.0 are in accord with the experimental results. The primary crystal field of slag of HCVTM is the melilite, and the liquidus temperature is 1409.81 °C; the primary crystal field of slag of VTM is CaTiO3, and the liquidus temperature is 1418.51 °C.

Metal-organic framework based in-syringe solid-phase extraction for the on-site sampling of polycyclic aromatic hydrocarbons from environmental water samples.

In-syringe solid-phase extraction is a promising sample pretreatment method for the on-site sampling of water samples because of its outstanding advantages of portability, simple operation, short extraction time, and low cost. In this work, a novel in-syringe solid-phase extraction device using metal-organic frameworks as the adsorbent was fabricated for the on-site sampling of polycyclic aromatic hydrocarbons from environmental waters. Trace polycyclic aromatic hydrocarbons were effectively extracted through the self-made device followed by gas chromatography with mass spectrometry analysis. Owing to the excellent adsorption performance of metal-organic frameworks, the analytes could be completely adsorbed during one adsorption cycle, thus effectively shortening the extraction time. Moreover, the adsorbed analytes could remain stable on the device for at least 7 days, revealing the potential of the self-made device for on-site sampling of degradable compounds in remote regions. The limit of detection ranged from 0.20 to 1.9ng/L under the optimum conditions. Satisfactory recoveries varying from 84.4 to 104.5% and relative standard deviations below 9.7% were obtained in real samples analysis. The results of this study promote the application of metal-organic frameworks in sample preparation and demonstrate the great potential of in-syringe solid-phase extraction for the on-site sampling of trace contaminants in environmental waters.

Analysis of physical composition and heavy metals pollution of municipal solid waste (MSW) in Beijing

By using on-site sampling and physical-chemical analysis, the physical composition and the contents of heavy metals in Beijing MSW were researched. The result showed that the main components of MSW in Beijing are mainly kitchen waste, the average content of kitchen waste are more than 60% and 50% in summer and in winter, respectively. The pollution of Cu, Hg and Cr are all more serious for MSW in Haidian and Dongcheng district. The heavy metal pollution of MSW in summer is higher than that in winter in Beijing. Seasonal impacts should be taken into consideration when dealing with MSW. The content of heavy metals in MSW exceeded the background value of soil in Haidian and Dongcheng districts. In order to reduce heavy metal pollution, the MSW should be separated collection and treated.

Mercury emissions monitoring in a coal-fired power plant by using the EPA method 30B based on a calcium-based sorbent trap

A novel calcium-based sorbent was synthesized from calcium acetate and mesoporous silica through chemical impregnation method. The Brunauer-Emmett-Teller (BET) and scanning electron microscope (SEM) analysis revealed that the sorbent possessed a good surface structure as the calcium salt decomposed to calcium oxide (CaO) through multiple calcination steps. The mercury adsorption performance of the sorbent was investigated in a fixed bed system, the results showed that the sorbent has an obvious penetration behavior for gaseous element mercury (Hg0(g)) while completely adsorbed reactive gaseous mercury (Hg2+(g)) under the pure nitrogen and simulated flue gas atmosphere. On-site sampling test of the calcium-based sorbent traps was ultimately conducted on a 600 MW coal-fired power plant. The Ontario Hydra Method (OHM) was chosen as the reference method to evaluate the accuracy of the sorbent traps sampling results. The measured data obtained by sorbent traps was well consistent with OHM under the selected operational load and all the sorbent traps passed the QA/QC criteria, show that the sorbent traps performed with almost the same accuracy as OHM. The mercury emission and removal characteristics across the existing air pollution control devices (APCDs) were reported based on the sorbent traps sampling results. With the help of SCR for the Hg0 oxidation, ESP for the removal of Hg2+ and Hgp, and the good water solubility of Hg2+ in WFGD, the combination of SCR + ESP + WFGD achieved an excellent mercury removal efficiency with the value of 88.54%. The final mercury emissions from the exhaust were 3.75 μg/m3 and meet the emission requirements of China.

Application of micro-solid-phase extraction for the on-site extraction of heterocyclic aromatic amines in seawater.

An efficient on-site extraction technique to determine carcinogenic heterocyclic aromatic amines in seawater has been reported. A micro-solid-phase extraction device placed inside a portable battery-operated pump was used for the on-site extraction of seawater samples. Before on-site applications, parameters that influence the extraction efficiency (extraction time, type of sorbent materials, suitable desorption solvent, desorption time, and sample volume) were investigated and optimized in the laboratory. The developed method was then used for the on-site sampling of heterocyclic aromatic amines determination in seawater samples close to distillation plant. Once the on-site extraction completed, the small extraction device with the analytes was brought back to the laboratory for analysis using high-performance liquid chromatography with fluorescence detection. Based on the optimized conditions, the calibration curves were linear over the concentration range of 0.05-20μg/L with correlation coefficients up to 0.996. The limits of detection were 0.004-0.026μg/L, and the reproducibility values were between 1.3 and 7.5%. To evaluate the extraction efficiency, a comparison was made with conventional solid-phase extraction and it was applied to various fortified real seawater samples. The average relative recoveries obtained from the spiked seawater samples varied in the range 79.9-95.2%.

In-syringe solid-phase extraction for on-site sampling of pyrethroids in environmental water samples

On-site sampling is an analytical approach that can ensure the accuracy of monitoring data and enhance the effectiveness of environmental protection measures. In the present work, an in-syringe solid-phase extraction (SPE) device was designed for on-site sampling of trace contaminants in environmental water samples followed by gas chromatography-mass spectrometry (GC-MS) analysis. Template assisted freeze casting followed by hydrazine vapor reduction approach was used to synthesize a hierarchical porous graphene aerogel (HPGA), which was used as the sorbent in the in-syringe SPE device. Environmental degradable pyrethroids were selected as the model analytes. Owing to the large specific surface area and hydrophobicity of HPGA, the target molecules could be completely extracted during one aspirating/dispensing cycle. The analytes were stable on the sorbent for at least 72 h when the device was stored under airtight and light-free conditions, and were not affected by the pH value of sample solution. All results demonstrated that the device could meet the requirements of on-site sampling. For practical application, the limits of detection were found to be in the range of 0.012–0.11 ng mL−1 under the optimized conditions, and satisfactory recoveries in the range of 65.7–105.9% were obtained for the analysis of real samples. The results of this study demonstrate the immense potential of HPGA for the enrichment of trace environmental pollutants, and meanwhile promote the application of the in-syringe SPE technique as a promising candidate for on-site sampling.

Effect of Harvest and Drying on Composition of Volatile Profile of Elderflowers (Sambucus nigra) from Wild

Volatile compounds emitted by elderflowers ( Sambucus nigra L.) at various stages (blooming on the bush, and at different stages after harvesting) were analyzed to investigate changes in the composition of volatile profiles induced by two drying procedures. Solid-phase microextraction and simultaneous distillation-solvent extraction were used for concentration of volatiles. Analyses of extracts were performed using gas chromatography coupled with a mass spectrometer or a flame ionization detector. On-site field sampling of volatiles followed-up by chromatographic analysis provided interesting information, including insect pheromones from 55 % to 79 % of the total peak area in the GC/MS chromatograms. Composition of aroma compounds of harvested elderflowers was strongly influenced by the type of drying procedure, where the content of some volatiles decreased and some substances even occur due to ongoing physicochemical processes. Changes in volatile profile caused by harvesting were also observed.

Modelling present and future permafrost thermal regimes in Northeast Greenland

Permafrost is vulnerable to rapid changes in climate, and increasing air temperatures have recently resulted in the increase of active layer thickness, thaw subsidence and warming of the underlying permafrost. Such changes have important implications for geotechnical properties and the stability of infrastructures in permafrost-affected areas. Many studies focus on the sensitivity of the active layer with respect to changes in climate conditions, but few assess the sensitivity of active layer thermal properties in relation to sediment types and soil water contents, and the importance of direct measurements of thermal property sensitivity with respect to soil water content compared to default physical relationships incorporated in process-based models. In this study, we use on-site data and samples to measure thermal conductivity (TC) at different gravimetric water/ice contents (GWC) in frozen and thawed permafrost. The samples, obtained from an emerged delta and an alluvial fan in the Zackenberg Valley, NE Greenland, are characterized by contrasting grain-size distribution and mineralogy. We calibrated a coupled heat and water transfer model, the “CoupModel”, to simulate permafrost temperatures at two sites on the delta. The sites have different snow depth characteristics and were simulated using both observed and default values of TC, and observed liquid soil water content. The results show that depth- and sediment type-specific TC values are crucial for a successful model simulation, and that transfer function derived values of TC are useful for modeling permafrost temperatures as long as site- and depth-specific grain size distribution and ice contents are defined. A thicker snow pack increased ground surface temperatures and resulted in a 1°C higher annual mean ground temperature at the depth of zero annual amplitude. Permafrost temperatures increased by 1.5°C and 3.5°C at the depth of 18m with 3°C and 6°C ground surface warming, but warming combined with increased soil water content had no important additional effect on the thermal regime when ground surface temperatures were prescribed as upper boundary conditions. Precipitation in the form of snow, however, may have a larger effect on ground temperatures directly, due to the surface temperature changes, than will the subsequent changes in thermal properties following increase in soil water content.