Flushing Time Versus Residence Time for the Great Bay Estuary

The terms “flushing time” and “residence time” have cropped up often in discussions about water quality and eelgrass health in the Great Bay Estuary. Flushing time and residence time are not the same thing and should not be used interchangeably. Flushing time is defined as the time it takes to replace a certain water mass in a coastal system and is most often used as a general measurement of water exchange in an estuary used to relate water exchange from one estuary to another. The most recent estimates of flushing time (2013) for the Great Bay are between 2.5 and 7 days. Residence time describes how long a parcel, starting from a specified location within a waterbody, will remain in the waterbody before exiting; residence time is more often used to understand or predict chemical and biological processes for a particular system. The most recent estimate of residence time for the Great Bay (2005) is between 5 and 20 days

Effects of CO2 flushing on crystal textures and compositions: experimental evidence from recent K trachybasalts erupted at Mt. Etna

Changes in magmatic assemblages and crystal stability as a response of CO2 flushing in basaltic systems have been never directly addressed experimentally, making the role of CO2 in magma dynamics still controversial and object of scientific debate. We conducted a series of experiments to understand the response of magmas from Etna volcano to CO2 flushing. We performed a first experiment at 300 MPa to synthesize a starting material composed of crystals of some hundreds of m and melt pools. This material is representative of an initial magmatic assemblage composed of plagioclase, clinopyroxene and a water undersaturated melt. In a second step, the initial assemblage was equilibrated at 300 and 100 MPa with fluids having different XCO2fl . Our experiments demonstrate that flushing basaltic systems with fluids may drastically affect crystal textures and phase equilibria depending on the amount of H2O and CO2 in the fluid phase. Since texture and crystal proportions are among the most important parameters governing the rheology of magmas, fluid flushing will also influence magma ascent to the Earths surface. The experimental results open new perspectives to decipher the textural and compositional record of minerals observed in volcanic rocks from Mt. Etna, and at the same time offer the basis for interpreting the information preserved in minerals from other basaltic volcanoes erupting magmas enriched in CO2

Power consumption of rock decomposition process during diamond core drilling using pulse flushing

Purpose. To study the impact of pulse flushing on the power consumption of rock decomposition during diamond core drilling. Methods. Theoretical analysis, processing of the obtained experimental data. Findings. The decrease in power consumption of rock decomposition process during drilling with jet pulse flushing was studied. The influence of the bottom-hole power and jet pulse flushing parameters on the efficiency of rock decomposition process was investigated. Physical mechanisms of mining rock degradation under the jet pulse flushing were considered in the article. Originality. It was established that the drilling performance is growing along with increasing of pauses between the flushing liquid supply intervals. At that, the relative reduction of energy consumption of the rock decomposition process is increasing when the bottom-hole power is decreasing. The study provides theoretical grounds for the increase in the mechanical rate of drilling during the jet pulse flushing owing to utilization of the generated frictional thermal energy in the bottom-hole. It is demonstrated that using pulse flushing intensifies the processes of thermal cycling degradation of the mining rock. Practical implications. It is demonstrated that the pulse flushing mode has a potential to improve the performance of diamond core drilling. The outcomes of the research can be useful for grounding the specifications of the jet pulse flushing method during the development of the energy saving modes of diamond core drilling processes.Мета. Дослідження впливу імпульсного режиму промивання на енергоємність процесу руйнування гірської породи при алмазному бурінні. Методика. Буріння здійснювалось по блоку граніту IX категорії за буримістю. Для проведення досліджень використано експериментальний стенд, що складається з бурового верстата ЗІФ-300 з додатковою коробкою передач і бурового насоса НБ-3. Для реєстрації та контролю режимних параметрів буріння використано витратомір ЕМР-2. В якості промивної рідини використовувалась вода. Буріння здійснювалося одношаровою алмазною коронкою 01А3 діаметром 59 мм з чотирма промивальним каналами. Результати. Визначено механічну швидкість буріння при різних видах промивання. Дано теоретичне обґрунтування збільшенню механічної швидкості буріння при імпульсному промиванні за рахунок використання теплової енергії тертя у вибої, що генерується. Встановлено, що збільшення механічної швидкості буріння можливо лише за рахунок зниження енергоємності процесу руйнування гірської породи. Досягнуто зниження енергоємності процесу руйнування породи при бурінні з імпульсним промиванням на 15.0 – 54.5%, при цьому з підвищенням рівня вибійної потужності енергоємність руйнування знижується як у випадку постійного промивання, так і в разі імпульсного. Встановлено, що ефективність термоциклічного впливу при алмазному бурінні з імпульсним промиванням залежить від фізико-механічних властивостей гірської породи. Наукова новизна. Виявлено, що ефективність процесу буріння зростає зі збільшенням паузи в подачі промивної рідини, при цьому відносне зниження енергоємності руйнування гірської породи збільшується при зменшенні рівня вибійної потужності. Практична значимість. Імпульсне промивання є резервом підвищення ефективності алмазного буріння. Результати дослідження представляють інтерес для обґрунтування параметрів технології імпульсного промивання при розробці енергоефективних режимів алмазного буріння.Цель. Исследование влияния импульсного режима промывки на энергоемкость процесса разрушения горной породы при алмазном бурении. Методика. Бурение выполнялось по блоку гранита IX категории по буримости. Для проведения исследований использован экспериментальный стенд, состоящий из бурового станка ЗИФ-300 с дополнительной коробкой передач и бурового насоса НБ-3. Для регистрации и контроля режимных параметров бурения использован расходомер ЭМР-2. В качестве промывочной жидкости использовалась вода. Бурение осуществлялось однослойной алмазной коронкой 01А3 диаметром 59 мм с четырьмя промывочными каналами. Результаты. Определена механическая скорость бурения при разных видах промывки. Дано теоретическое обоснование увеличения механической скорости бурения при импульсной промывке за счет использования генерируемой тепловой энергии трения в забое. Установлено, что увеличение механической скорости бурения возможно только за счет снижения энергоемкости процесса разрушения горной породы. Достигнуто снижение энергоемкости процесса разрушения породы при бурении с импульсной промывкой на 15.0 – 54.5%, при этом с повышением уровня забойной мощности энергоемкость разрушения снижается как в случае постоянной промывки, так и в случае импульсной промывки. Установлено, что эффективность термоциклического воздействия при алмазном бурении с импульсной промывкой зависит от физико-механических свойств горной породы. Научная новизна. Выявлено, что эффективность процесса бурения возрастает с увеличением паузы в подаче промывочной жидкости, при этом относительное снижение энергоемкости разрушения горной породы увеличивается при уменьшении уровня забойной мощности. Практическая значимость. Импульсная промывка является резервом повышения эффективности алмазного бурения. Результаты исследования представляют интерес для обоснования параметров технологии импульсной промывки при разработке энергоэффективных режимов алмазного бурения.The present study was based on the results of the experimental research into the process of diamond core drilling in pulse flushing mode within the frames of projects implemented by the Department of Deposits Prospecting Technique at the National Mining University (Dnipro University of Technology, Dnipro, Ukraine). The authors hereby express their gratitude to all colleagues at the Department of Deposits Prospecting Technique who took part in the experimental research

Remediation of Contaminated Soils by Solvent Flushing

Solvent flushing is a potential technique for remediating a waste disposal/spill site contaminated with organic chemicals. This technique involves the injection of a solvent mixture (e.g., water plus alcohols) that enhances contaminant solubility, reduces the retardation factor, and increases the release rates of the contaminants. A simulation model is developed to predict contaminant elution curves during solvent flushing for the case of one‐dimensional, steady flow through a contaminated medium. Column experiments are conducted with a Eustis fine sand that is initially equilibrated with an aqueous naphthalene solution, and then eluted with different methanol‐water mixtures to remove the naphthalene. The model simulations, based on parameter values estimated from literature data, agree well with the measured elution profiles. Solvent flushing experiments, where the soil was initially equilibrated with a solution of naphthalene and anthracene, show that compounds with different retardation factors are separated at low cosolvent contents, while coelution of the compounds occurs at higher contents. In general, the smaller the retardation factor in water and the higher the cosolvent fraction, the faster the contaminant is recovered. The presence of nonequilibrium conditions, soil heterogeneity, and type of cosolvent will influence the time required to recover the contaminant.\u

EFFECTIVE SEDIMENT CONTROL IN A RESERVOIR

Sedimentation in a reservoir cannot be avoided. The average rate of sedimentation on the storage volume reduction of a reservoir in the world is about 1 % per year (Yoon,1992), meanwhile, the storage volume reduction in several reservoir in Indonesia reaches 1,64% to 2,83% per year (Atmojo,2012). These sediment’s accumulations in the reservoir will continually reduce the storage volume, thus the intended functions of reservoirs for flood control (Atmojo, 2013), irrigation and water supply, electric generation, etc. will also reduced and not optimal. Some of sediment control measures have been practiced in reducing sediment accumulation in reservoirs around the world. In principle, there are two approaches i.e., reduce the sediment input to a reservoir by land conservation, construction of check dam, sand pocket, diversion channel, etc. and reduce the sedimentation in the reservoir by sluicing, turbidity current, dredging, and flushing (Morris and Fan, 1998; Emamgholizadeh et al., 2006). This paper presents the performance of sediment’s reduction from a reservoir by flushing, sluicing, and disturbing flushing based on some laboratories results (Atmojo,2012). It is expected that this paper can contribute to elicits some finding on the selection of which suitable method for sediment reduction from a reservoir

Variable-Volume Flushing (V-VF) device for water conservation in toilets

Thirty five percent of residential indoor water used is flushed down the toilet. Five out of six flushes are for liquid waste only, which requires only a fraction of the water needed for solid waste. Designers of current low-flush toilets (3.5-gal. flush) and ultra-low-flush toilets (1.5-gal. flush) did not consider the vastly reduced amount of water needed to flush liquid waste versus solid waste. Consequently, these toilets are less practical than desired and can be improved upon for water conservation. This paper describes a variable-volume flushing (V-VF) device that is more reliable than the currently used flushing devices (it will not leak), is simple, more economical, and more water conserving (allowing one to choose the amount of water to use for flushing solid and liquid waste)

Collection and freezing of equine epididymal spermatozoa

The epididymis and vas deferens store an important number of fertile spermatozoa called the extragonadal sperm reserves. These stored spermatozoa can be collected in an ultimate attempt to preserve viable spermatozoa of a critically ill or dying stallion. Epididymides are collected via routine castration. After cooled transport of the testicles and epididymides, spermatozoa are collected either by retrograde flushing or by the float-up method. Retrograde flushing usually results in a much higher sperm yield and is considered the method of choice. Epididymal spermatozoa can be frozen using standard freezing protocols

Density-Dependent and -Independent Behaviors of the Adult Karner Blue (Lycaeides Melissa Samuelis) (Lepidoptera: Lycaenidae)

At 146 pine-oak barrens in central and northwestern Wisconsin USA during 1988-96, 3973 Karner blues (Lycaeides melissa samuelis Nabokov) were found in 95.4 hr of transect surveys during spring and 6896 individuals in 134.8 hr during summer. Of these, 9346 (86%) individuals were first observed copulating, feeding, flushing, flying, or involved in a non-copulatory intraspecific interaction. All these behaviors except copulation showed density-independent influences; all these behaviors also had density-dependent influences. The most frequently significant density-independent variables affecting occurrence of these behaviors were temperature, brood (spring vs. summer), and crepuscularity (time since noon). Male (rather than female or overall) Karner blue density more often significantly related to Karner blue behavior. Males showed density dependence in feeding (positive), flushing (negative), and flying (positive threshold) while females did not. Both sexes showed strong positive density dependence in non-copulatory intraspecific interactions and copulation. Flying and intraspecific interactions showed similar influences in relation to several variables, while flying and flushing had markedly opposite patterns. Males and females were also opposite in their relative tendency to be observed flushing or flying, with females more likely to be flushing, males flying. Males also showed a greater tendency to engage in non-copulatory intraspecific interactions

Language, Immigration and Acculturation in the Short Stories of Ha Jin

The Problems of Acculturation: Flushing, Queens, in the Short Stories of Ha Jin Abstract: Noted author Ha Jin is often thought of as a Chinese author despite the fact that all of his writing has been written in English. Two of his later works, A Free Life (2007) and A Good Fall (2009) are set among the Chinese community in Flushing, Queens. This essay examines three short stories An English Professor, A Pension Plan, and Temporary Love from A Good Fall. In these works, Jin discusses the problems of acculturation these immigrants face, including learning English, finding employment, and dealing with forced separation. The stories depict the treacherous territory the immigrants, as well as the author himself at times, traverse as they dwell between two languages, two cultures, two literatures, two countries