bluuebunny/crossref_metadata_2025 huggingface dataset:
Genesis of massive ice at ‘Ice Mountain’, Yenesei River, Western Siberia, according to results of gas analyses
Authors: Arkhangelov A. A. , Novgorodova E. V.
Published: February 2007

Analyses of the gas composition of bubbles in the massive ice at Ice Mountain, made for the first time, enable one to conclude that the origin of ice is glacial.

O2, H2, CO2, N2, He and CH4 were determined. Our genetic proof is based on the principally different bio‐ and chemical gas contents in intrasedimental and surface ice. That is why we also deduce the data on the ice of clear genesis: modern glaciers and injection ice.

Gas composition seems to be an important criterion of ice genesis and this method should be applied to other massive ice bodies of unknown origin.
Weathering by segregation ice growth in microcracks at sustained subzero temperatures: Verification from an experimental study using acoustic emissions
Authors: Hallet B. , Walder J. S. , Stubbs C. W.
Published: February 2007

In a continuing effort to better understand the frost‐induced breakdown of rock, experiments were designed specifically to assess a theoretical model of crack propagation due to segregation ice growth in water‐saturated rocks with interconnected cracks (Walder and Hallet, 1985). A rectangular block of Berea Sandstone was frozen unidirectionally while the temperature and acoustic emissions, which reflect microfracture propagation events, were monitored. Acoustic emissions were counted and approximately located as a function of time and temperature while the rock sample was subjected to a fixed temperature gradient.

The experimental results indicate considerable frost damage to sandstone due to ice growth in an open system with migration of water to freezing centres much as segregation ice grows in soils, as has been previously suggested. Freezing‐induced microfracture propagation events are not associated with the freezing temperature, which is about —0.2 ºC for Berea Sandstone; most of the fracture activity occurs at distinctly lower temperatures, between —3 ºC and —6 ºC, in accord with our theoretical predictions. Such microfracturing does not require freeze‐thaw cycling or even falling temperatures; temperatures were held constant but spatially nonuniform for the duration of most experiments.

Through a series of experiments other aspects of the model are being tested and the influence of lithology is being examined. Diverse geomorphic implications of this model are discussed because it offers attractive alternative insights to those available with the conventional view of frost weathering. A plea is made to strive towards a more fundamental and unified view of frost weathering and related phenomena.
Frost weathering of rocks in the presence of salts‐a review
Authors: Williams R. B. G. , Robinson D. A.
Published: February 2007

In many temperate and cold regions, rocks containing salt in solution are subject to frost action. Although the salts depress the freezing point of water, their most common effect at subzero temperatures is to increase the intensity of rock breakdown. Different mechanisms to explain why salts often accelerate frost weathering are outlined and their possible applicability to the weathering of different rocks undergoing different frost regimes is assessed. It is concluded that, because different salt solutions exhibit different crystallization behaviour at subzero temperatures, resulting in varied proportions of water, ice and salt crystals, more than one mechanism is likely to be responsible for rock breakdown. The importance of the different mechanisms will vary with the composition and strength of the salt solution, the temperature regime, the rock type and other factors.
A solifluction meter for permafrost sites
Authors: Lewkowicz Antoni G.
Published: February 2007

A solifluction meter that measures soil movements at eight levels in the active layer is described. Anchored in permafrost, the meter transforms mechanical movement of wooden blocks attached to flexible racks into changes in the electrical resistance of potentiometers. Solifluction can be monitored continuously with a data‐logger or manually at intervals when visiting field sites. Preliminary results from meters installed on the Fosheim Peninsula, Ellesmere Island, illustrate frost creep, with heave continuing at ground temperatures between −25°C and −30°C, and summer movements of the active layer in response to thaw consolidation and precipitation.
Dynamics of rock glaciers of the Northern Tien Shan and the Djungar Ala Tau, Kazakhstan
Authors: Gorbunov Aldar P. , Titkov Sergei N. , Polyakov Victor G.
Published: February 2007

Over 1500 active rock glaciers have been identified in the Northern Tien Shan and the Djungar Ala Tau, Kazakhstan. Studies of the dynamics of six near‐glacier rock glaciers for 15–60 years show rates of movement in the main body of the rock glacier of 0.16–14.0 m/y. These also vary with time. Factors involved include climatic change, changes in ice content in the source area, flow of glacial meltwater through the rock glacier, changes in gradient of the underlying surface and changes in width of the valley through which it moves.
Small‐scale patterned ground, Comeragh Mountains, southeast Ireland
Authors: Wilson Peter
Published: February 2007

Small‐scale, active patterned ground features (stripes and nets) are described for the first time from Ireland. Present‐day frost‐related processes are thought to be responsible for much of the surface morphology displayed by the patterns.
Interactions and relations between mountain permafrost, glaciers, snow and water
Authors: Harris Stuart A. , Corte Arturo E.
Published: February 2007

There are problems in determining the amount of precipitation at a given site in mountain permafrost areas, because snow can be redistributed by wind or avalanches. Both snow and rain greatly affect permafrost distribution. Surface soil conditions also affect permafrost distribution. Dry blocky surfaces, peaty soils and soils with a thick organic mat tend to favour permafrost development. Active layers are deepest on dry mineral soils at low latitudes. Moist soils have thin active layers which exhibit the zero curtain effect during freezing and thawing. Meteoric H2O enters permafrost in response to thermal gradients. The H2O content may reach 80% by volume in its upper layers in some rock glaciers. In Kazakhstan a perched water table occurs above the thawing front in the active layer and provides a reliable supply of water to plants, so that the permafrost lands have a lush meadow tundra in summer. The physical and chemical properties of the discharge from mountain permafrost areas can be used to differentiate it from glacial discharge and groundwater. There is an antipathetic relationship between the lower limit of permafrost and the equilibrium line on glaciers. Gorbunov's Continentality Index is the only system for classifying the climate of mountain permafrost areas that indicates their great climatic variability.
Permafrost creep and rockglaciers
Authors: Barsch Dietrich
Published: February 2007

Active rockglaciers are discussed as the visible expression of creep of alpine or mountain permafrost. They are mainly formed below talus slopes (talus rockglaciers) and below lateral and terminal moraines (debris rockglaciers). Rockglaciers prefer continental, comparatively dry, winter‐cold mountains. They are not well developed in high maritime and humid tropical mountains. Active rockglaciers are indicators of active mountain permafrost and, thus, of great geoecological information value.
Alpine periglacial landforms of eastern North America: A review
Authors: Clark G. Michael , Schmidlin Thomas W.
Published: February 2007

Permafrost and periglacial features occur at high elevations in the mountains of New England (Presidential Range), Gaspésie, Western Newfoundland and Labrador. Both active and inactive patterned ground features have been reported together with block fields and felsenmeer. Problems relate to the complex deglaciation histories of the areas in question, the possibility that nunataks existed during the last glaciation, and the role of cold‐based versus warm‐based ice in landform preservation. There is need for more research on periglacial features and deposits in the alpine zone of eastern North America.
Active rock glaciers and the lower limit of discontinuous alpine permafrost, Khumbu Himalaya, Nepal
Authors: Jakob Matthias
Published: February 2007

Seismic refraction studies were carried out on four rock glaciers in the Khumbu Himalaya near the Poklade massif (27°55′ N, 86°50′ E) and its surroundings. P‐wave velocities at profiles on southeast‐facing slopes indicate that the lower limit of discontinuous alpine permafrost is between 5560 m and 5360 m a.s.l. On west‐facing slopes the lower limit varies between 4959 m and 5050 m a.s.l. These values agree with elevations of active rock glacier termini.
Rock glaciers and periglacial phenomena in the southern Carpathians
Authors: Urdea Petru
Published: February 2007

Glacial and periglacial phenomena in the southern Carpathians are an undoubted reality. Climatic conditions and lithology favour the existence of rock glaciers, block fields, cryoplanation terraces, ploughing blocks and solifluction. The highest frequency and the most complex of rock glaciers are found in granites and granodiorites within northerly cirques and valleys of the Paring and Retezat Mountains, whereas less frequent and predominantly embryonic, protalus rampart‐type forms occur in epimetamorphic precrystalline schists. Water temperatures below 2 °C of the springs emerging in summer from the fronts of some rock glaciers point to local permafrost conditions possibly still existing today.
High‐latitude rock glaciers: A case study of forms and processes in the Canadian arctic
Authors: Evans David J. A.
Published: February 2007

Rock glaciers in the Phillips Inlet/Wootton Peninsula area of northwest Ellesmere Island are of the talus‐foot or valley‐side type and all lie below 180 m a.s.l. The rock glaciers are located predominantly below extensive bedrock gullies at the base of steep fiord and U‐shaped valley walls. Two types of rock glacier of talus‐foot type exist in the area. (1) Glacier ice‐cored rock glaciers occur above marine limit and coincide with projected margins of former glaciers which are demarcated by the use of glacimarine and sea level evidence. Because these rock glaciers are discontinuous and have not been carried down flow line, they probably relate to catastrophic slope failures over stagnant ice. (2) Permafrost‐related rock glaciers lie either below marine limit, especially in areas of heavy glacierization by floating glaciers, or in areas of former ice‐dammed lakes. The fine‐grained sediments appear to provide a deformable substrate and/or the perfect medium for the development of substantial interstitial ice. The initiation of all rock glaciers in this environment relates to the palaeogeography of the last glaciation; glacier ice‐cored (glacial) rock glaciers occur at former glacier margins and permafrost‐related (periglacial) rock glaciers occur below the marine limit associated with those glacier margins.
Investigations of cryogenic weathering in Europe and Northern Asia
Authors: Konishchev V. N. , Rogov V. V.
Published: February 2007

Recent Russian investigations into cold climate (i.e. cryogenic) weathering are reviewed. Data obtained from both experimental and field studies upon rock breakdown are summarized and values of cryogenic stability and cryogenic contrast are presented for different mineral assemblages and for rocks of different ages. Unconsolidated ice‐rich sediments are emphasized.
Permafrost changes in Europe during the last glacial
Authors: Vandenberghe J. , Pissart A.
Published: February 2007

Reconstruction of former permafrost is based on specific indicators which represent relics of features developed above or within the permafrost. Their interpretation in terms of genesis and (palaeo)climatic significance, however, is in some cases still under debate. Previously the reconstruction of the periglacial environment in Europe was limited to permafrost mapping during the coldest time of the last glaciation. Today a much more refined evolution of the palaeoclimate of the last glacial has been established, thanks to a considerable increase in registered periglacial indicators, a better understanding of the corresponding climate conditions, and more accurate and reliable dating of the periglacial phenomena.
Permafrost zonation in Russia under anthropogenic climatic change
Authors: Nelson Frederick E. , Anisimov Oleg A.
Published: February 2007

Warming induced by the hypothesized greenhouse effect will have profound consequences for permafrost distribution throughout the high‐latitude regions of the globe. Two scenarios of climate change based on the palaeo‐reconstruction method widely employed by Russian scientists were used in conjunction with a model that produces zonal maps of permafrost distribution. Changes associated with both 1.2°C and 2.0°C warming of the mean global temperature are amplified in the high latitudes, which results in the potential for a large reduction of the area underlain by continuous permafrost. Thermokarst development is likely to be particularly acute in the West Siberian plain, where the climate model suggests that conditions will become marginal for the maintenance of permafrost.
Mountain permafrost and climatic change
Authors: Haeberli W. , Guodong Cheng , Gorbunov A. P. , Harris S. A.
Published: February 2007

Perennially frozen slopes occur in many mountain ranges of the world. Ice‐rich debris or morainic material especially exist under subcontinental to continental‐type climatic conditions with elevated glacier equilibrium lines. Such supersaturated mountain permafrost exhibits pronounced creep movements, thereby forming large numbers of rock glaciers. Reconstructions of late‐glacial palaeotemperature and palaeoprecipitation using combined glacier/permafrost studies reveal dramatic changes in permafrost belts and in the periglacial environments of mountain areas during the pronounced late‐glacial warming. As a consequence of atmospheric warming during the first half of the twentieth century, the lower boundary of mountain permafrost distribution in various mountain ranges such as the Alps may have shifted in altitude, causing local degradation of formerly frozen slopes. Continued or even accelerated future warming is likely to induce further retreat and degradation of high‐altitude permafrost.
Coastal dune development in a thermokarst environment: Some implications for environmental reconstruction, Tuktoyaktuk Peninsula N.W.T.
Authors: Ruz Marie‐Hélène
Published: February 2007

The landscape of the Tuktoyaktuk Peninsula coastal plain, Northwest Territories, has been strongly affected by thermokarst processes. Along thermokarst lakes developed in glacio‐fluvial sands lake‐shore dunes are common. Their formation seems related to complete or partial lake drainage. During the Holocene the rise of relative sea level has induced the submergence of the coastal plain that extended offshore of the present‐day coastal lowlands. Today coastal retreat rates in excess of 1 m/yr result in thermokarst lakes breaching and landward migration of spits and barrier‐islands. A unique type of coastal dune has been observed along two coastal sections. Late Holocene lake‐shore dunes are eroded alongshore and capped by modern coastal dunes. These coastal dunes developed in a thermokarst environment are indicators of lake drainage probably induced by late Holocene sea level rise.
Fabric analysis of rock glacier debris mantles, La Sal Mountains, Utah
Authors: Nicholas Joseph W.
Published: February 2007

Macrofabrics of rock glacier debris mantles display significant variation even among similar microtopographic features. Fabrics of longitudinal ridges of La Sal rock glaciers are equally divided between cluster and girdle distributions. In some cases, fabric patterns resemble those of lahars, implying that the flow mechanics of rock glaciers bears some similarity to that of large‐scale debris flows. Shear zones are found at the margins of many longitudinal ridges, and in at least one case these zones separate the rock glacier from a pair of bounding ridges that resemble debris‐flow levees. Other sites display fabric patterns that indicate that the dominant processes are dry creep of the open‐matrix debris mantle. Weak fabrics are found at sites where rockfall inputs occur on a low‐angle surface, or where a debris mantle is undergoing passive transport by a moving core.
Structures Sédimentaires d'un Cǒne de Flots de Débris (Vars, Alpes Françaises Méridionales)
Authors: Bertran Pascal , Texier Jean‐Pierre
Published: February 2007

Des coupes réalisées dans un cǒne de flots de débris alpin ont mis en évidence une stratification, dont la physionomie varie en fonction de la distance à l'apex du cǒne. Dans les fadès proximaux, la stratification est discontinue et constituée par des lentilles de cailloutis ouvert dans un diamiction. L'origine des cailloutis est discutée à la lumière des figures sédimentaires observées dans un flot récent. La partie distale du cǒne est caractérisée par l'interstratification de lobes, de colluvions et de paléosols. Stratification, fabriques et microstructures sont significativement différentes de celles produites par la solifluxion et peuvent constituer des figures diagnostiques pour reconnaǐtre les dépǒts fossiles.
Burial mound permafrost in the altai
Authors: Gorbunov Aldar , Gorbunova Irina
Published: February 2007

In the Altai permafrost exists which is confined to burial mounds dated at 2000‐2500 years old. This indicates that, under favourable conditions, permafrost may occur at elevations 1000m lower than is commonly believed at present.
Permafrost distribution in the southern circumpolar region and its relation to the environment: A review and recommendations for further research
Authors: Bockheim James G.
Published: February 2007

Because of basal melting beneath the massive Antarctic ice sheet, permafrost probably comprises less than 25% of the Southern Circumpolar Region (c. ≥ 50°S latitude). Permafrost is pervasive in ice‐free areas of Antarctica and its offshore islands but is lacking in the sub‐Antarctic islands, except possibly at the higher elevations. Based on limited data, the thickness of permafrost ranges from 100 to 1000m in ice‐free areas of Antarctica. The thickness of the active layer ranges between 50 and 150 cm in the Antarctic islands and maritime East Antarctica and 15 and 50 cm in interior Antarctica. Ground ice is restricted to rock glaciers and ice wedges; the rock glaciers, palsa and thermokarst reported in some areas originate from ice‐cored drift and not permafrost. Active and inactive patterned ground occurs throughout the region. Whereas sorted circles, nets, and stripes are common in the Antarctic islands and in maritime East Antarctica, ice‐ and sand‐wedge polygons are prevalent in ice‐free valleys of Antarctica. Altiplanation terraces may exist in the Antarctic islands and in maritime East Antarctica; however, landforms in interior Antarctica are controlled more by salt weathering than by cryogenic processes. Based‐on the presence of inactive rock glaciers, gelifluction lobes, and large‐scale patterned‐ground features, permafrost was probably present in the sub‐Antarctic islands during the last glaciation. Recommendations are made for future work in the region.
Enseignements de i'étude Morphosédimentaire de la Grézière de Tilly‐sur‐Meuse
Authors: Harmand D. , Deshaies A. Weisrock Et M.
Published: February 2007

La grézière de Tilly‐sur‐Meuse, située sur le versant ouest de la vallée de la Meuse lorraine, à 20 km au sud de Verdun, présente plusieurs cǒnes surbaissés coalescents de grèze, euxměmes constitués de trois formations. Les trois formations sont constitutées de la base vers le sommet par: des grèzes inférieures, jaunes et à litage centimétrique, coïncidant avec des cǒnes progradant vers le nord‐est (ces grèzes forment l'essentiel du dépǒt): des grèzes médianes, alternativement brunes et jaunes, correspondant à un dépǒt d'intercone; des grèzes supérieures coïncidant avec un nouveau cone progradant vers l'est. Les grèzes des trois formations sont essentiellement des grèzes maigres ‐ la part des éléments fins excède rarement quelques pour cent ‐ composées surtout d'éléments de la taille des graviers: les éléments de taille supérieure à 2 mm représentent souvent plus de la moitié de l'échantillon. Ceci est directement lié a la nature lithologique des calcaires sublithographiques de l'Oxfordien moyen, qui fournissent fort peu de matériaux fins. Ces grèzes ont été affectées par des processus post‐sédimentaires: cryoturbation, alteration et induration.
Le Rǒle des Coulées de Pierres Sèches dans la Genèse d'un Certain Type d'Éboulis Stratifiés
Authors: Hétu Bernard , van Steijn Henk , Bertran Pascal
Published: February 2007

Des expériences de coulées sèches artificielles (grain flow) effectuées dans la carrière de Bélesten (Pyrénées) et les observations réalisées (levés stratigraphiques, analyses sédimentologiques) dans le cǒne stratifié artificiel de la carriére de Remollon (Alpes du Sud), construit au convoyeur et évoluant exclusivement par coulées sèches, ont permis d'élaborer un nouveau modèle de stratogenèse. Dans ce modèle, les lits fins sont constitués de matériel infiltré à la base d'un flux relativement rapide de pierraille openwork en état de dilatation du fait des multiples collisions interparticules (effet de crible). Une fois en place, ces lits fins servent de plan de glissement pour les coulées sèches suivantes qui descendent ainsi de plus en plus bas sur le versant. Les lits grossiers, caractérisés par une texture ouverte, un granoclassement inverse marqué et une forte imbrication des éléments, correspondent aux lobes terminaux des coulées sèches qui viennent peu à peu recouvrir leur plan de glissement suivant un processus de fossilisation remontante. Le modèle des coulées sèches rend compte de manière satisfaisante des principales caractéristiques de l'éboulis stratifié relique de Bélesten, un type d'éboulis qui semble très répandu tant dans les Pyrénées que dans les Alpes. Nécessitant un renouvellement constant des stocks de débris à la těte de I'éboulis, les coulées sèches évoluent dans des roches trés gélives se débitant en menus fragments, mais livrant peu d'éléments fins. La coulée sèche est un processus ubiquiste signalé aussi bien dans les régions chaudes et arides que dans les zones tempérées et périglaciaires. Les éboulis reliques à coulées sèches n'ont done pas de signification paléoclimatique spécifique. Il est clair cependant que dans le contexte des moyennes latitudes, les paysages ouverts et à forte productivité détritique (cryoclastie) des périodes froides du Pléistocène leurs étaient spécialement favorables.
Cryogenic landslides on the Yamal Peninsula, Russia: Preliminary observations
Authors: Leibman Marina O.
Published: February 2007

Certain processes occurring in the northern part of the permafrost zone pose hazards for construction. These include cryogenic landslides. Three types are discussed for the Yamal Peninsula: shearing slides (active layer detachment failures), ground ice slumps, and earth flows. The first prevail in size and number.
A preliminary MTD‐PLS study for androgen receptor binding of steroid compounds
Authors: Bora Alina , Seclaman E. , Kurunczi L. , Funar‐Timofei Simona
Published: February 2007

The relative binding affinities (RBA) of a series of 30 steroids for Human Androgen Receptor (AR) were used to initiate a MTD‐PLS study. The 3D structures of all the compounds were obtained through geometry optimization in the framework of AM1 semiempirical quantum chemical method. The MTD hypermolecule (HM) was constructed, superposing these structures on the AR‐bonded dihydrotestosterone (DHT) skeleton obtained from PDB (AR complex, ID 1I37). The parameters characterizing the HM vertices were collected using: AM1 charges, XlogP fragmental values, calculated fragmental polarizabilities (from refractivities), volumes, and H‐bond parameters (Raevsky's thermodynamic originated scale). The resulted QSAR data matrix was submitted to PCA (Principal Component Analysis) and PLS (Projections in Latent Structures) procedure (SIMCA P 9.0); five compounds were selected as test set, and the remaining 25 molecules were used as training set. In the PLS procedure supplementary chemical information was introduced, i.e. the steric effect was always considered detrimental, and the hydrophobic and van der Waals interactions were imposed to be beneficial. The initial PLS model using the entire training set has the following characteristics: R2Y = 0.584, Q2 = 0.344. Based on distances to the model criterions (DMODX and DMODY), five compounds were eliminated and the obtained final model had the following characteristics: R2Y = 0.891, Q2 = 0.591. For this the external predictivity on the test set was unsatisfactory. A tentative explanation for these behaviors is the weak information content of the input QSAR matrix for the present series comparatively with other successful MTD‐PLS modeling published elsewhere. © 2007 Wiley Periodicals, Inc. Int J Quantum Chem, 2007
Porous graphitic carbon chromatography/tandem mass spectrometric determination of cytarabine in mouse plasma
Authors: Hsieh Yunsheng , Duncan Christine J.G. , Brisson Jean‐Marc
Published: February 2007

A high‐performance liquid chromatography (HPLC) system using a porous graphitic carbon (PGC) stationary phase interfaced with an electrospray ionization (ESI) source and a tandem mass spectrometer (MS/MS) for the analysis of cytarabine (ara‐C) in mouse plasma samples has been developed in support of a pharmacodynamic study. The graphitized carbon column was adopted for the separation of ara‐C and endogenous peaks from mouse plasma samples under the reversed‐phase phase mode in liquid chromatography. The retention characteristics of the PGC column and the ionization efficiencies of all analytes based on the experimental factors such as the composition of mobile phases were investigated. The potential of ionization suppression resulting from the endogenous biological matrices on the PGC column during HPLC/ESI‐MS/MS was investigated using post‐column infusion. The concentrations of ara‐C in mouse plasma obtained by using PGC‐HPLC/MS/MS and ion‐pairing HPLC/MS/MS were found to be in good agreement in terms of analytical accuracy. © 2007 John Wiley & Sons, Ltd.
Ruggedness testing of quantitative atmospheric pressure ionization mass spectrometry methods: the effect of co‐injected matrix on matrix effects
Authors: Heller David N.
Published: February 2007

A number of techniques have been suggested to date for assessing matrix effects on quantitative atmospheric pressure ionization mass spectrometry (API‐LC/MS) methods. A newly designed experiment has the aim of efficiently simulating the quantitative behavior of an LC/MS method as a function of the amount of co‐injected matrix extract. Two sets of mixtures were prepared in different formats to study matrix effects as a function of analyte or matrix amount. Chromatographic conditions were varied as well, to alter the separation between analyte and co‐extractants, and thereby provide different matrix effect conditions for testing the same mixtures. Graphical presentation of the results was used to gain insight into the matrix effect phenomenon. The results suggest that ruggedness for API‐LC/MS methods may be defined as the absence of significant variation in results as a function of the amount of co‐injected matrix. That is, a non‐rugged API‐LC/MS method may give consistent results only if a fixed amount of matrix is co‐injected on a specific instrument. The results also point to the existence of a specific matrix concentration for the onset of matrix effects, below which these effects are not significant. These issues are important to the US FDA Center for Veterinary Medicine, which has regulatory authority for methods used to monitor for drug residues in food tissues from animals. The ruggedness testing technique suggested here may be an important factor in determining that a method is ready for multi‐laboratory testing on multiple instruments. Published in 2007 by John Wiley & Sons, Ltd.
Simultaneous quantification of acylcarnitine isomers containing dicarboxylic acylcarnitines in human serum and urine by high‐performance liquid chromatography/electrospray ionization tandem mass spectrometry
Authors: Maeda Yasuhiro , Ito Tetsuya , Suzuki Atsuko , Kurono Yukihisa , Ueta Akihito , Yokoi Kyoko , Sumi Satoshi , Togari Hajime , Sugiyama Naruji
Published: February 2007

Tandem mass spectrometry (MS/MS) has become a prominent method for screening newborns for diseases such as organic acidemia and fatty acid oxidation defects, although current methods cannot separate acylcarnitine isomers. Accurate determination of dicarboxylic acylcarnitines such as methylmalonylcarnitine and glutarylcarnitine has not been carried out, because obtaining standards of these acylcarnitines is difficult. We attempted the individual determinations of acylcarnitines with isomers and dicarboxylic acylcarnitines by applying high‐performance liquid chromatography (HPLC). Chromatographic separation was performed by gradient elution using a mixture of 0.08% aqueous ion‐pairing agent and acetonitrile as the mobile phase. Mass transitions of m/z 161.8→84.8 for carnitine and m/z 164.8→84.8 for deuterated carnitine were monitored in positive ion electrospray ionization mode. One carnitine and 16 acylcarnitines were quantified. The limit of quantitation (LOQ) was 0.1 µmol/L for methylmalonylcarnitine and 0.05 µmol/L for the other acylcarnitines. Intra‐day and inter‐day coefficients of variance (CVs) were <8.3% and <8.8%, respectively, for all acylcarnitines in serum, and both were <9.2% in urine. Mean recoveries were >90% for all acylcarnitines. Human samples were quantified by this method. After addition of deuterated acylcarnitines as internal standards, acylcarnitines in serum or urine were extracted using a solid‐phase extraction cartridge. In healthy adult individuals, isobutyryl‐, 2‐methylbutyryl‐ and isovalerylcarnitine were detected in serum and urine. Dicarboxylic acylcarnitines were detected in urine. High concentrations of methylmalonylcarnitine and propionylcarnitine were found in both the serum and the urine of a patient with methylmalonic acidemia. The described HPLC/MS/MS method could separate most acylcarnitine isomers and quantify them, potentially allowing detailed diagnoses and follow‐up treatment for those diseases. © 2007 John Wiley & Sons, Ltd.
Slurry‐phase bioremediation: Case studies and cost comparisons
Authors: Ross Derek
Published: February 2007

Slurry‐phase biological treatment is a relatively new development for the remediation of hazardous wastes, offering significant advantages over other bioremediation technology currently in use. It is highly effective for a variety of wastes, and its rate of degradation is up to ten times faster than land treatment.
Interim pump‐and‐treat remediation of a hydrocarbon‐contaminated aquifer
Authors: Johnson Robert E.
Published: February 2007

The continuous and discontinuous release of petroleum hydrocarbons from an oil refinery in Alaska resulted in the contamination of an unconfined glacial outwash aquifer. Geologic conditions at the site allowed for the vertical migration of hydrocarbon product to the water table and subsequent formation of an areally extensive floating product layer. Since the petroleum hydrocarbon phase would provide a major source of BTX (benzene, toluene, xylene) contamination to the groundwater, interim product and groundwater recovery measures were initiated to limit aquifer degradation. Phase I remedial activities involved the operation of nine well pairs, with one well used for groundwater extraction and the other for product recovery. Phases II and III involved expansion of the recovery well network and use of a two‐pump system. Petroleum product recovered was reprocessed at the refinery. Contaminated groundwater was initially treated using the refinery's wastewater treatment system, but treatment inefficiencies and continued system expansion necessitated use of a separate treatment unit. Performance evaluations indicate that the remedial phases have been successful in halting further contaminant migration and in recovering a significant volume of the released petroleum hydrocarbons.
Fluidized bed PCB incineration in Alaska
Authors: Diot Harold R. , Young Derrell T.
Published: February 2007

Ogden Environmental Services Inc. (OES) is operating a PCB incineration project on the Kenai Peninsula, Alaska. The facility is approximately 150 miles from Anchorage, Alaska, on a U.S. Fish and Wildlife Service refuge and recreation area. Before attaining its current status, the area was an oil field; pipelines and compressor stations are still in the area. Ogden's facilities are located adjacent to an operating compressor station in an area transected by pipelines. The site became contaminated with PCBs as an indirect result of a compressor explosion in 1972. In March 1988 OES contracted to remediate the site using its proprietary transportable Circulating Bed Combustor (CBC), an advanced technology fluidized bed incinerator.

The project will thermally treat more than 80,000 tons of PCB‐contaminated soil. Treated soil (ash) contains less than 0.1 ppm PCB and is permanently placed on site. Ogden designed, constructed, permitted, conducted trial burns, and made fully operational this major facility on the remote Kenai Peninsula of Alaska. All systems were designed to withstand the rigors of shipping and to be highly reliable in cold weather and remote‐site operations.
New paradigms for hazardous waste engineering
Authors: Wallace William A.
Published: February 2007

Today's hazardous waste engineering practice is based on the premise that the current technologies for conducting hazardous waste remediation are sufficient to solve most problems. The premise is false: Except for simple sites, the current practice cannot deliver answers with the required accuracy and precision. This article describes the huge uncertainties present in complex hazardous waste remediation efforts. It also discusses the “observational” method, which originated in the geotechnical engineering field, as a means of coping with these uncertainties during site characterization and remediation. The article includes case‐study examples illustrating the use of the observational method at hazardous waste sites.
Managing petroleum refining wastes by thermal desorption
Authors: McCabe Mark M. , Wilkins James , Cunningham Robert
Published: February 2007

The U.S. Environmental Protection Agency has developed regulations under the Hazardous and Solid Waste Amendments (HSWA) of 1984 to restrict the land disposal of hazardous wastes. As a result of the regulations, all hazardous wastes to be placed on the land must meet treatment standards based on the performance of the best demonstrated available technology (BDAT) identified for individual waste classifications.

The Marathon Oil Company is currently evaluating innovative technologies for managing listed waste materials, with a focus on waste minimization and recycling. Remediation Technologies, Inc. (ReTeC) has conducted testing on wastewater treatment sludges from three Marathon refineries using a proprietary thermal desorption technology. The results from these tests have demonstrated that the technology has the ability to consistently meet BDAT treatment standards, while preferentially separating and condensing residual moisture and oils from the material.
Semivolatile organic decay rates in pilot‐scale solid‐ and slurry‐phase bioreactors
Authors: Yare Bruce S.
Published: February 2007

A variety of process byproducts and residues were reclaimed at the Brio Refining Superfund site, an abandoned jet fuel refinery located near Houston, Texas. Among the operations that took place at the site were regeneration of acrylonitrile synthesis catalysts, styrene reprocessing still bottoms to recover ethylbenzene, and the attempted reclamation of 1,2‐dichloroethane from vinyl chloride process residues. Incoming process byproducts and residues were stored in unlined impoundments before reclamation, until the Texas Air Control Board had the impoundments closed under court order in 1979. After the pits were closed, two pilot‐scale bioremediation demonstrations were performed on the backfilled impoundments. The results of these studies indicated that bioremediation of the organic residues and affected soils at the site was included as an acceptable treatment technology in the Record of Decision. This article compares the degradation rates achieved by the two different biological treatment processes used to treat the organic material in the impoundments.
Can in situ vitrification seal arsenic/mercury sludges into a delisted glass monolith?
Authors: Jacobson Linda S. , Mears Connally E.
Published: February 2007

The U.S. Environmental Protection Agency helped select in situ vitrification (ISV) as an interim response action for the National Priority List (NPL) site at the Rocky Mountain Arsenal (RMA) in Commerce City, Colorado. That decision is being reviewed, pending redesign of the technology by its vendor for what would be the largest ISV project in the United States, involving 220 tons of arsenic, twenty‐six tons of mercury, and low levels of organic compounds. That material was left in three arsenic precipitation basins that were used from 1942 to 1947 to manufacture chemical warfare agents and later backfilled. This article explores the eight principal environmental, technical, and financial factors that EPA's Region VII must address before committing $1,200 per cubic yard, or $14 million, to seal that material in glass.
Expert software that matches remediation site and strategy
Authors: Pennock Kelly A. , Bohn Shawn J. , White Michael K.
Published: February 2007

Expert software‐based decision support is speeding the process of defining environmental hazards and identifying remedial responses for the U.S. Department of Energy's (DOE) hazardous waste cleanup projects throughout the United States. Pacific Northwest Laboratories' (PNL) Remedial Action Assessment System (RAAS), and associated Technology Information System (TIS), written for Macintosh computers (soon for PC‐compatible computers), sort through an encyclopedic data base to help environmental engineers prepare the most appropriate remedial strategy. The system has been available to DOE and other U.S. government engineers since last year and will soon be commercially available.
Let biodegradation promote in‐situ soil venting
Authors: Newman William A. , Martinson Michael M.
Published: February 2007

Although vapor extraction systems (VES) certainly help remediate volatile hydrocarbons (e.g., gasoline in unsaturated soils), recent studies have found that much of the related hydrocarbon removal is due to aerobic biodegradation, not simple volatilization. In many cases, more than 50 percent of the hydrocarbon removal by these systems is due to biodegradation. By emphasizing biodegradation and minimizing volatilization, the costs of system operation can be reduced, especially for off‐gas treatment. Maximizing biodegradation also supports more efficient site remediation because not only are the volatile hydrocarbons cleaned up, but the less volatile contaminants are also cleaned up—by biodegradation. More complete site cleanups are possible through bioventing, especially when cleanup criteria are related to total petroleum hydrocarbons. This article explores the major environmental conditions that influence biodegradation, analyzes several bioventing case histories, and calculates biodegradation's remedial costs.
Integrated bioremediation of soil and groundwater at a superfund site
Authors: Piotrowski Michael R. , Doyle J. Robert , Carraway James W.
Published: February 2007

The soil and two aquifers under an active lumber mill in Libby, Montana, had been contaminated from 1946 to 1969 by uncontrolled releases of creosote and pentachlorophenol (PCP). In 1983, because the contaminated surface soil and the shallower aquifer posed immediate risks to human health and the natural environment, the U.S. Environmental Protection Agency placed the site on its National Priorities List. Feasibility studies in 1987 and 1988 determined that in situ bioremediation would help clean up this aquifer and that biological treatment would help clean up the contaminated soils. This article outlines the studies that led to a 1988 EPA record of decision and details the EPA‐approved remedial plan implemented starting in 1989; EPA estimates a total cost of about $15 million (in 1988 dollars). The plan involves extensive excavation and biological treatment of shallow contaminated soils in two lined and bermed land treatment units, extraction of heavily contaminated groundwater, an aboveground bioreactor treatment system, and injection of oxygenated water to the contaminant source area, as well as to other on‐site areas affected by the shallower aquifer's contaminant plume.
How shell cleaned up a 400,000‐gallon oil spill
Authors: Fischel Marion , Fraser John P. , Winfield Ted P.
Published: February 2007

On April 23, 1988, approximately 9,500 barrels (400,000 gallons) of San Joaquin Valley crude oil leaked from an aboveground storage tank at Shell Oil Company's Martinez Manufacturing Complex in Martinez, California and entered Suisun Bay, an important recreation area. This article describes the remediation techniques Shell used to protect and clean up the Bay's oiled marshes, sloughs, rocky shores, marinas, and sandy beaches, and discusses the main methods of oil spill response, site‐specific factors that must be considered in choosing remediation techniques, the interaction between Shell and government agencies, and the costs associated with the spill. The cleanup's total cost was approximately $8.3 million, which did not include private claims and claims handling costs; Shell also signed a separate consent decree for $19.75 million with the state of California and the federal government. This spill and its aftermath emphasize the need for preparation that facilitates response actions, improves the chances for cooperation between responsible parties and government agencies, minimizes the time needed for remediation, lowers cleanup costs, and limits natural resource damage claims and penalties.
Hydrogen peroxide for physicochemically degrading petroleum‐contaminated soils
Authors: Watts Richard J.
Published: February 2007

Catalyzed hydrogen peroxide was applied to contaminated soil at an equipment storage yard in Reno, Nevada, that had also been used as a dump for motor oil and diesel fuel for twenty years. The site is only a quarter mile from the Truckee River—a principal source of Reno's drinking water. This article details hydrogen peroxide's advantages, disadvantages, costs, and treatment for reducing to below the 100 mg/kg Nevada action level the petroleum hydrocarbons in the yard's arid soil, which is characterized by low organic carbon content and low manganese oxide content.
Pure oxygen‐enhanced biodegradation for contaminated groundwater
Authors: Quinlan Barbara J. , Korreck William M. , Armstrong John M.
Published: February 2007

On‐site oxygen generation was chosen as the most effective and efficient source of pure oxygen for enhancing biodegradation at a hydrocarbon‐contaminated oil and gas well site in northern Michigan. Contaminants include benzene, toluene, ethylbenzene, and xylenes released through natural gas dehydration practices that were halted in 1985. Free product and contaminated soil were completely removed from the source area in spring 1989, leaving only the groundwater plume for further remediation. This article discusses the project's two phases—a purge and treat system and the pure‐oxygen bioremediation system—each costing $75,000. It also details the combined system's technical elements (including purge and monitoring wells, oxygen generator, and drainfield), and cleanup results (including how pure oxygen has helped destroy contaminants, not merely move them to other media).
How chemically stable is stabilized hazardous waste?
Authors: Peterson Spencer A. , Barich John J. , Greene Joe C.
Published: February 2007

Bioassays can provide meaningful information about the relative toxicity of remediated soil samples, revealing the unwelcome toxic side effects produced by some cleanup projects. Section 121 of CERCLA's 1986 amendments calls for hazardous waste site remediations to permanently and significantly reduce the volume, toxicity, and mobility of hazardous substances, pollutants, and contaminants. Traditional engineering technology has focused on reducing volume and mobility, assuming that such reduction would lead to reductions in toxicity. Environmental scientists have argued, however, that such reductions are not always the result, but lack of consensus on how hazardous waste mixtures should be measured toxicologically has slowed development of integrated assessments. The aquatic and terrestrial bioassays discussed in this article are evaluated for various chemicals, mixtures of chemicals, and actual waste site chemical mixtures at a Superfund mobility reduction project in Kent, Washington. Results suggest that although remediation accomplished the primary objective of reducing mobility, it also introduced toxic effects. These tradeoffs must be viewed holistically when the ultimate performance of cleanup measures is judged.
Cleanup levels for pcbs and their combustion products at an industrial facility
Authors: LaGoy Peter K. , Garrett Jennifer S.
Published: February 2007

In 1991, a fire occurred at a foundry in western Pennsylvania. The fire started in capacitors that contained polychlorinated biphenyls (PCBs) and subsequent sampling has indicated that PCBs and products of their incomplete combustion, the polychlorinated dibenzo‐p‐dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs), were released as a result of the fire. This article develops and provides justification for site‐specific cleanup levels for the PCBs, PCDDs, and PCDFs accidentally released into this industrial facility during the fire. Cleanup levels were calculated using standard risk assessment approaches and assumptions, and these riskbased values were compared with cleanup criteria used for other sites. Final criteria were established based on this comparison and a consideration of such site‐specific factors as migration potential, industrial use patterns, and the small mass of material present.
Limitations on infiltration and reinjection of treated groundwater to remove trace amounts of pesticides in groundwater and soil
Authors: Foulk Cary L. , Bost Richard C.
Published: February 2007

Infiltration and reinjection of treated groundwater have been used to increase the recovery of pesticide‐related constituents at a pesticide formulation plant that produces consumer pesticide products. The stratigraphy at the site consists of silty and sandy clay deposits overlying a shallow silt, sand, and gravel aquifer. The groundwater and soils in two areas in the northwest portion of the property have been identified as being significantly affected by pesticide and pesticide‐related compounds.

An integrated system of soil removal, recovery wells, injection wells, an infiltration gallery, and a cut‐off wall was selected as the best remedial alternative. Groundwater modeling, column tests, biological jar tests, and a pilot test demonstrated the feasibility of the system. The affected groundwater is treated to drinking‐water quality by a system of filtering and carbon adsorption. Approximately 75 percent of the treated water is reinjected or allowed to infiltrate through the vadose zone, and the remainder is discharged to the local sewer system. Initially, the system was effective in removing the dissolved, suspended, and weakly adsorbed constituents. Subsequently, the recovery rate of the chemical constituents became dependent on chemical and physical processes related to the presence of residual amounts of dense, nonaqueous phase liquids and the clay content of the strata. The rate of pesticide recovery has decreased because of the retarding effect of the clay and the low solubility of the pesticides.