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1
Vermeulen, Ivar, Anika Batenburg, Camiel J. Beukeboom, and Tim Smits. "Breakthrough or One-Hit Wonder?" Social Psychology 45, no. 3 (May 1, 2014): 179–86. http://dx.doi.org/10.1027/1864-9335/a000182.
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Three studies replicated a classroom experiment on single-exposure musical conditioning of consumer choice ( Gorn, 1982 ), testing whether simultaneous exposure to liked (vs. disliked) music and a pen image induced preferences for the shown (vs. a different) pen. Experiments 1 and 2 employed the original music, Experiment 3 used contemporary music. Experiments 2 and 3 employed hypothesis-blind experimenters. All studies incorporated post-experimental inquiries exploring demand artifacts. Experiments 1 and 2 (original music; N = 158, N = 190) showed no evidence for musical conditioning, and were qualified (conclusive) replication failures. Experiment 3 (contemporary music; N = 91) reproduced original effects, but with significantly smaller effect size. Moreover, it had limited power and showed extreme scores in one experimental group. Aggregated, the three studies produced a null effect. Exploration of demand artifacts suggests they are unlikely to have produced the original results.
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Heijman, S. G. J., W. Siegers, R. Sterk, and R. Hopman. "Prediction of breakthrough of pesticides in GAC-filters and breakthrough of colour in ion-exchange-filters." Water Supply 2, no. 1 (January 1, 2002): 103–8. http://dx.doi.org/10.2166/ws.2002.0013.
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Adsorption columns are widely used in drinking water treatment to improve a number of water quality parameters. Granular activated carbon filtration (GAC) can be used to decrease the concentration of DOC, colour, taste, odour and pesticides. Columns filled with ion-exchange resins are used to remove colour, nitrate and DOC. The regeneration frequency of these types of filters depends strongly on the natural water quality. Especially the DOC-concentration and DOC-composition determines the efficiency of the processes. Because pilot-plant experiments with realistic contact-times will last for more than a year (for GAC) there is a need for a prediction of breakthrough based on shorter and less expensive laboratory experiments. The available models are not accurate enough because the exact parameters are not available. In batch experiments with natural water, with realistic (low) pesticide concentrations and the full grain size of the adsorbent the adsorption parameters are measured in an independent experiment. With the parameters obtained with these experiments an accurate prediction of the breakthrough curve is possible. With the same parameters predictions of breakthrough curves are calculated under different process conditions. The possibilities of process optimisation can reduce the investment costs for new full-scale plants.
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Doelle, Meinhard. "The Paris Agreement: Historic Breakthrough or High Stakes Experiment?" Climate Law 6, no. 1-2 (May 6, 2016): 1–20. http://dx.doi.org/10.1163/18786561-00601001.
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This article offers an overview of the two key outcomes of the 2015 Paris climate negotiations, the Paris cop decision, and the Paris Agreement. Collectively, they chart a new course for the un climate regime that started in earnest in Copenhagen in 2009. The Paris Agreement represents a path away from the top-down approach and rigid differentiation among parties reflected in the Kyoto Protocol, toward a bottom-up and flexible approach focused on collective long-term goals and principles. It represents an approach to reaching these long-term goals that is focused on self-differentiation, support, transparency, and review. The article highlights the key elements of the agreement reached in Paris, including its approach to mitigation, adaptation, loss and damage, finance, transparency, and compliance.
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Schmid, Bernhard H., Michael A. Hengl, and Ursula Stephan. "Density effects on salt tracer breakthrough curves from constructed wetland ponds." Hydrology Research 35, no. 3 (June 1, 2004): 237–50. http://dx.doi.org/10.2166/nh.2004.0017.
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Salt tracer experiments are a convenient method to determine travel time distributions in constructed wetland ponds. Typically, these flows are characterized by low Reynolds numbers at times even within the laminar flow regime. In this environment the injection of salt may cause strong density effects, thereby jeopardizing the usefulness of the recorded breakthrough curves. After a tracer experiment has been completed, an indication of potential density stratification in the field may be noticed in the form of surprisingly small recovery rates of a tracer considered as nearly conservative. To provide a tool that permits the intended experiment to be judged at the planning stage already, criteria have been developed that yield approximate maximum concentrations, not to be exceeded if density effects shall be avoided. Laboratory experiments were carried out and the newly derived relationships applied with success. The criteria may in future be useful, too, in the planning of tracer experiments in slowly flowing rivers and streams.
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Sobotková, Martina, Michal Sněhota, Eva Budínová, and Miroslav Tesař. "Isothermal and non-isothermal infiltration and deuterium transport: a case study in a soil column from a headwater catchment." Journal of Hydrology and Hydromechanics 65, no. 3 (September 1, 2017): 234–43. http://dx.doi.org/10.1515/johh-2017-0029.
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AbstractIsothermal and non-isothermal infiltration experiments with tracer breakthrough were carried out in the laboratory on one intact column (18.9 cm in diameter, 25 cm in height) of sandy loam soil. For the isothermal experiment, the temperature of the infiltrating water was 20°C to the initial temperature of the sample. For the two non-isothermal experiments water temperature was set at 8°C and 6°C, while the initial temperature of the sample was 22°C. The experiments were conducted under the same initial and boundary conditions. Pressure heads and temperatures were monitored in two depths (8.8 and 15.3 cm) inside the soil sample. Two additional temperature sensors monitored the entering and leaving temperatures of the water. Water drained freely through the perforated plate at the bottom of the sample by gravity and outflow was measured using a tipping bucket flowmeter. The permeability of the sample calculated for steady state stages of the experiment showed that the significant difference between water flow rates recorded during the two experiments could not only be justified by temperature induced changes of the water viscosity and density. The observed data points of the breakthrough curve were successfully fitted using the two-region physical non-equilibrium model. The results of the breakthrough curves showed similar asymmetric shapes under isothermal and non-isothermal conditions.
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Lu, Pei-Jen, Chih-Sheng Chang, and Jia-Ming Chern. "Binary adsorption breakthrough curves in fixed bed: Experiment and prediction." Journal of the Taiwan Institute of Chemical Engineers 45, no. 4 (July 2014): 1608–17. http://dx.doi.org/10.1016/j.jtice.2013.10.018.
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Lupas, Andrei N., Joana Pereira, Vikram Alva, Felipe Merino, Murray Coles, and Marcus D. Hartmann. "The breakthrough in protein structure prediction." Biochemical Journal 478, no. 10 (May 24, 2021): 1885–90. http://dx.doi.org/10.1042/bcj20200963.
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Proteins are the essential agents of all living systems. Even though they are synthesized as linear chains of amino acids, they must assume specific three-dimensional structures in order to manifest their biological activity. These structures are fully specified in their amino acid sequences — and therefore in the nucleotide sequences of their genes. However, the relationship between sequence and structure, known as the protein folding problem, has remained elusive for half a century, despite sustained efforts. To measure progress on this problem, a series of doubly blind, biennial experiments called CASP (critical assessment of structure prediction) were established in 1994. We were part of the assessment team for the most recent CASP experiment, CASP14, where we witnessed an astonishing breakthrough by DeepMind, the leading artificial intelligence laboratory of Alphabet Inc. The models filed by DeepMind's structure prediction team using the program AlphaFold2 were often essentially indistinguishable from experimental structures, leading to a consensus in the community that the structure prediction problem for single protein chains has been solved. Here, we will review the path to CASP14, outline the method employed by AlphaFold2 to the extent revealed, and discuss the implications of this breakthrough for the life sciences.
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Streb, Anne, and Marco Mazzotti. "Adsorption for efficient low carbon hydrogen production: part 1—adsorption equilibrium and breakthrough studies for H2/CO2/CH4 on zeolite 13X." Adsorption 27, no. 4 (March 1, 2021): 541–58. http://dx.doi.org/10.1007/s10450-021-00306-y.
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Abstract Reforming of fossil fuels coupled with carbon capture and storage has the potential to produce low-carbon H2 at large scale and low cost. Adsorption is a potentially promising technology for two key separation tasks in this process: H2 purification and CO2 capture. In this work, we present equilibrium adsorption data of H2 and CH4 on zeolite 13X, in addition to the already established CO2 isotherms. Further, we carry out binary (CO2–CH4) and ternary (H2–CO2–CH4) breakthrough experiments at various pressures and temperatures to estimate transport parameters, assess the predictive capacity of our 1D column model, and compare different multi-component adsorption models. CO2 adsorbs strongly on zeolite 13X, CH4 adsorbs less, and H2 adsorbs very little. Thus, H2 breaks through first, CH4 second (first in the binary breakthrough experiments) and CO2 last. Linear driving force (LDF) mass transfer coefficients are estimated based on a single breakthrough experiment and mass transfer is found to be fast for H2, slower for CH4, and slowest for CO2. The LDF parameters can be used in a predictive manner for breakthrough experiments at varying pressures, temperatures, flows, and, though with lower accuracy, even compositions. Heat transfer inside the column is described well with a literature correlation, thus yielding an excellent agreement between simulated and measured column temperatures. Ideal and real adsorbed solution theories (IAST and RAST, respectively) both model the observed breakthrough composition profiles well, whereas extended isotherms are inferior for predicting the competitive behavior between CH4 and CO2 adsorption. This study provides the groundwork necessary for full cyclic experiments and their simulation.
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Brookbank, C. Roy. "The Nova Scotia Experiment in Labour Management Relations." Relations industrielles 20, no. 3 (April 12, 2005): 478–513. http://dx.doi.org/10.7202/027585ar.
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The following study constitutes a breakthrough in the field of behaviour sciences applied to labour-management relations. This paper is a description and an interpretation of the organizational pattern and the type of behaviour dynamics which emerged in the course of the experiment under the guidance of the Institute of Public Affairs at Dalhousie University.
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Guo, Ping, Shiyong Hu, Yisheng Hu, and Qijian Ding. "Experimental Study on Gas Breakthrough Prevention by Flue Gas Drive." E3S Web of Conferences 218 (2020): 02022. http://dx.doi.org/10.1051/e3sconf/202021802022.
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The heterogeneity of glutenite reservoir is serious, and breakthrough is easy to occur in the process of water drive and gas drive, which reduces the sweep efficiency. The serious vertical heterogeneity in the H well area of Xinjiang oilfield led to the rapid gas breakthrough during gas injection test. Water alternating gas flooding and foam profile control are often used to seal breakthrough. In this paper, based on the actual reservoir characteristics, vertical heterogeneous planar model is made for flooding experiment. The experimental results show that after gas breakthrough caused by water alternating gas flooding, the flue gas foam can effectively block the high permeability layer and develop the low permeability layer, improve the sweep efficiency and recovery percent, and provide reference for the development adjustment of actual reservoir after gas breakthrough.
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Masruroh, Kuni, Rochim Bakti Cahyono, Imam Prasetyo, and Teguh Ariyanto. "The Effect of Amine Types on Breakthrough Separation of Methane on Biogas." International Journal of Renewable Energy Development 10, no. 2 (December 15, 2020): 149–55. http://dx.doi.org/10.14710/ijred.2021.33514.
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Methane (CH4) and carbon dioxide (CO2) are the main components of a renewable energy source of biogas. Separation of CO2 from biogas is significantly important to improve biogas performance, due to heating value in biogas depends on the concentration of methane. One of the gas separation technologies that has been widely used in chemical industries is carbon molecular sieve (CMS). This research explores the potential of CMS for biogas purification. CMS was prepared by modification of palm kernel shell-derived porous carbon using amine groups such as monoethanolamine (MEA), 2-amino-2-methyl-1-propanol (AMP), and diethanolamine (DEA). The effect of amine types on the separation parameters was studied by using a breakthrough experiment to obtain the most potential CMS materials. The methods of this research include the process of carbon oxidation using hydrogen peroxide, impregnation with an amine group, characterization of the CMS material obtained, CO2 and CH4 gas separation testing with a breakthrough system. The CMS was characterized by using N2 sorption analysis, fourier transform infrared spectroscopy, and scanning electron microscopy. The breakthrough experiment showed that CMS-MEA had the highest performance for separating CO2 and CH4 gases. In addition, the results also showed that loading of amine groups on carbon caused an increase in the uptake capacity of CO2, and the highest capacity was achieved by CMS-MEA of 13.2 mg/g.
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Malecki, Paweł. "Pacific Ocean Neutrino Experiment." Universe 10, no. 2 (January 23, 2024): 53. http://dx.doi.org/10.3390/universe10020053.
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Following the breakthrough discoveries of very-high-energy neutrinos of astrophysical origin by IceCube, a new field of research, neutrino astronomy, was established in the previous decade. Even though two extragalactic point sources of such neutrinos have been identified by now, TXS 0506+056 and NGC 1068, the origin and processes of the creation of astrophysical neutrinos are still mostly unexplored. To advance quickly in this new field, more neutrino telescopes are needed. This article describes the current status and plans for the development of the Pacific Ocean Neutrino Experiment (P-ONE), which is under construction in the Pacific Ocean near Vancouver Island. The deployment of P-ONE is expected to start in 2025, exploiting the already available deep-sea infrastructure provided by Ocean Networks Canada. P-ONE will complement the existing IceCube, Baikal-GVD, and KM3NeT neutrino telescopes not only with its large detection volume, but also by providing insight into the southern celestial hemisphere, where the central region of the Galactic Plane is located.
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Xiao, Juanjuan, Yufeng Xiao, Xinmin Ge, and Tianqi Zhou. "A Technique to Determine the Breakthrough Pressure of Shale Gas Reservoir by Low-Field Nuclear Magnetic Resonance." Energies 15, no. 19 (October 1, 2022): 7223. http://dx.doi.org/10.3390/en15197223.
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The porous and low-permeability characteristics of a shale gas reservoir determine its high gas storage efficiency, which is manifested in the extremely high breakthrough pressure of shale. Therefore, the accurate calculation of breakthrough pressure is of great significance to the study of shale gas preservation conditions. Based on a systematic analysis of a low-field NMR experiment on marine shales of the Longmaxi Formation in the Sichuan Basin, a shale gas breakthrough pressure determination technique different from conventional methods is proposed. The conventional methods have low calculation accuracy and are a tedious and time-consuming process, while low-field NMR technique is less time-consuming and of high accuracy. Firstly, the NMR T2 spectrum of shale core sample in different states is measured through low-field NMR experiment. The NMR T2 spectra of sample in water-saturated state and dry state are combined to model the mathematical relationship between shale gas breakthrough pressure and NMR T2 spectrum. It is found that the gas breakthrough pressure is power-exponentially related to the geometric mean of NMR T2 spectrum and positively related to the proportion of micropores. Accordingly, the shale gas breakthrough pressure is quickly and accurately calculated using continuous NMR logging data and then the sealing capacity of the shale caprocks is evaluated, providing basic parameters for analyzing unconventional hydrocarbon accumulation, preservation and migration. This technique has been successfully applied with actual data to evaluate the sealing capacity of shale caprock in a shale gas well in the Sichuan Basin. It can provide a good basis for the evaluation and characterization of shale oil and gas reservoirs.
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Li, Qiumei, and Lijun Wei. "Research and design of high-performance DSP control system based on frequency control." Highlights in Science, Engineering and Technology 7 (August 3, 2022): 151–56. http://dx.doi.org/10.54097/hset.v7i.1037.
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With the rapid development of power electronic devices and microprocessors, AC variable frequency and speed regulating system has also made a breakthrough. The thesis introduces the hardware circuit design based on TMS320F28335, and the result of the experiment proves the SVPWM algorithm is correct. It also does some research on VF control system of the inverter and the result of the experiments proves that the control system achieves the purpose, and has a quick dynamic response.
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Zhu, Yucheng, Shuchuan Peng, Ping Lu, Tianhu Chen, and Yan Yang. "Mercury Removal from Aqueous Solutions Using Modified Pyrite: A Column Experiment." Minerals 10, no. 1 (December 31, 2019): 43. http://dx.doi.org/10.3390/min10010043.
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Modified pyrite (MPy), which was obtained from calcination in an N2 atmosphere, was used as a sorbent for removing Hg(II) from aqueous solutions. Fixed-bed column experiments were conducted to determine the Hg(II) removal ability of MPy from aqueous solutions. MPy was found to be much better than natural pyrite for mercury removal. The concentration of Hg(II) in effluents was much lower than that of the emission standard used for Hg wastewater in China (0.05 mg/L), and the removal efficiency of Hg(II) was greater than 99% before breakthrough. When the capacity was 3274 times the column bed volume (1 bed volume = 25.12 cm3), the column breakthrough and the sorption amount of Hg(II) were 54.44 mg/g. The Hg(II) content in the used MPy sorbent was up to 24.79%. The mechanism was analyzed by X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), field emission transmission electron microscopy (FE-TEM), and X-ray Photoelectron Spectroscopy (XPS). The main mechanism of Hg(II) removal by MPy was the chemical reactions between mercury ions and mineral fillers, and HgS precipitated on the surface of MPy to remove Hg(II). The reaction was also accompanied by surface complexation and adsorption. The results of this work show that MPy can be used as a sorbent for continuous Hg(II) removal.
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Zhang, Lei, Feng Lan Zhao, and Ji Rui Hou. "Experimental Study of Improving the CO2 Flooding Development Effect in Ultra-Low Permeability Reservoir." Advanced Materials Research 594-597 (November 2012): 2470–74. http://dx.doi.org/10.4028/www.scientific.net/amr.594-597.2470.
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In order to improve the development effect of Chang-6 Oil Reservoir, five sets of different production pressure (1MPa, 2MPa, 3MPa, 4MPa, 5MPa) was designed to do CO2 immiscible flooding experiment to analyze the channeling laws. The experimental results showed that gas breakthrough time and gas channeling time were all shortened with the increasing of the pressure difference, but the ultimate recovery had a fluctuation change, increasing first and decreasing afterwards. And the production sharply increased in the gas breakthrough before and after. The best displacement effect was in 3MPa differential pressure. Then plugging experiment was made under the condition of 3MPa differential pressure, isopropyl amine was as plugging channeling agent. The experimental results: the residual resistance coefficient of plugging channeling agent was 8.56, and the range of enhancing recovery efficiency was 15%.
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Gruznov, Vladimir M., and Alexander B. Vorozhtsov. "Gas-Dynamic Kinetics of Vapour Sampling in the Detection of Explosives." Molecules 24, no. 23 (December 3, 2019): 4409. http://dx.doi.org/10.3390/molecules24234409.
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The dynamic sorption concentration of explosive vapours on concentrators made of a metal mesh, and the transportation of explosive vapours through the extended metal channels are considered. The efficiency of the concentration and transportation is determined by the breakthrough of the substance’s molecules through the channels. The research methods we used were breakthrough calculation theory and experiment. When calculating the breakthrough, a mesh was presented as a set of parallel identical channels. Wire mesh and extended channels were made of stainless steel. The breakthrough is determined through the specific frequency of the collisions between the molecules and the channel’s surface. This is presented as a function of the ratio of the substance diffusion flow to the channel’s surface to the airflow through the channel. The conditions for high-speed concentration, complete capture of explosive vapours, and low vapour losses during their transportation through the extended channels were determined theoretically and experimentally. For a concentrator made of a mesh, the condition of a high concentration rate at a high breakthrough (up to 80%) was determined. The described sorption concentration is used in portable gas chromatographic detectors of explosive vapours of the EKHO series.
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Kulyakorn, Khuanmar, Thoungshone Satawat, and Somboot Pattakamol. "Removal of Red Acid Dye from Synthetic Wastewater by Adsorption onto Low-Cost Material." Advanced Materials Research 156-157 (October 2010): 375–78. http://dx.doi.org/10.4028/www.scientific.net/amr.156-157.375.
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Low-cost adsorbent which was burned rice husk was used in this study. The burned rice was tested with a series of packed bed in plastic bottle. The flow rate was controlled at 0.1 ml/s for all the experiment. Thomas model was used to predict the breakthrough time and all experiments were carried out at room temperature. The results indicated that the burned rice husk has a potential to be low-cost adsorbent for removal of red acid dye
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Selmert, Victor, Ansgar Kretzschmar, Hans Kungl, Hermann Tempel, and Rüdiger-A. Eichel. "Breakthrough analysis of the CO2/CH4 separation on electrospun carbon nanofibers." Adsorption 30, no. 1 (January 2024): 107–19. http://dx.doi.org/10.1007/s10450-023-00435-6.
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AbstractThe removal of the main impurity CO2 is a crucial step in biogas upgrading. In this work, the separation of CO2 from CH4 on electrospun polyacrylonitrile-based carbon nanofibers (CNFs) is investigated using breakthrough experiments. The CNFs are prepared at various carbonization temperatures ranging from 600 to 900 °C and feature a tailorable pore size that decreases at higher carbonization temperatures. The adsorption properties of the different CNFs are studied measuring pure component isotherms as well as column breakthrough experiments. Adsorption kinetics are discussed using a linear driving force approach to model the breakthrough experiment and obtain the adsorption rate constant. Moreover, different approaches to determine the selectivity of the competitive CO2/CH4 adsorption are applied and discussed in detail. The results clearly prove that a size exclusion effect governs the adsorption selectivity on the CNFs. While CH4 cannot adsorb in the pores of CNFs prepared at 800 °C or above, the smaller CO2 is only excluded from the pores of CNFs prepared at 900 °C. For CNFs carbonized in the range from 600 to 750 °C, values of the CO2/CH4 selectivity of 11–14 are obtained. On the CNFs prepared at 800 °C the CH4 adsorption is severely hindered, leading to a reduced adsorbed amount of CH4 and consequently to an improved CO2/CH4 selectivity of 40. Furthermore, owing to the shrinking pores, the adsorption rates of CH4 and CO2 decrease with higher carbonization temperature.
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Liu, Jia, Wei Xia, Weijun Mu, Peizhou Li, Yanli Zhao, and Ruqiang Zou. "New challenge of metal–organic frameworks for high-efficient separation of hydrogen chloride toward clean hydrogen energy." Journal of Materials Chemistry A 3, no. 10 (2015): 5275–79. http://dx.doi.org/10.1039/c4ta06832g.
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Eleven metal–organic frameworks are used for H2/HCl separation by real breakthrough experiment and molecular dynamic simulations, affording clean hydrogen energy resource with purity >99.997% from chlor-alkali industry exhaust.
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Morgan, Michael K., Ian Johnston, Michael Besser, and David Baines. "Cerebral arteriovenous malformations, steal, and the hypertensive breakthrough threshold." Journal of Neurosurgery 66, no. 4 (April 1987): 563–67. http://dx.doi.org/10.3171/jns.1987.66.4.0563.
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✓ An experiment was designed to investigate the effects of arteriovenous (AV) fistula occlusion on cerebral autoregulation. A right carotid-jugular fistula was created in 63 rats in such a way as to produce an intracranial AV fistula with a loop extension into the neck. The fistula was occluded after an 8-week interval with the rats under both normotension and metaraminol-induced hypertension, and evidence of blood-brain barrier disruption was investigated with an Evans blue dye technique. The results indicate that an intracranial AV fistula may cause cerebral steal which is responsible for a reduction in the threshold for hypertensive breakthrough following fistula occlusion.
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Ranucci, G., and E. Meroni. "Counting test facility for the Borexino experiment." International Journal of Modern Physics A 29, no. 16 (June 17, 2014): 1442001. http://dx.doi.org/10.1142/s0217751x14420019.
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A fundamental breakthrough which opened the way to the realization of the Borexino detector was the demonstration of exceptionally low, unprecedented radioactive contaminations in the liquid scintillator, obtained with its pilot prototype Counting Test Facility. Though of limited dimension, with its 4.8 m3 of active liquid core, CTF has however been a key milestone not only for Borexino, but also for the entire field of the ultra-low background searches. Here, we succinctly remind the motivations, which concurred to lay down the project, as well as the specific radiopurity challenge, which guided the design. After the description of the technical elements of the detector, the main outcomes are summarized, both regarding optical and purity scintillator properties, with special emphasis on the exceptional achievements in term of ultra-low traces of radioactive contaminants. The discussion is completed with the description of how CTF was employed for the pre-qualification of the entire inventory of the Borexino scintillator, confirming also in the final phase of its life its essential role for the success of the overall Borexino solar neutrino program.
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Han, Sheng Chao, Yan Chen, Jiu Hua Xu, and Jing Wen Zhou. "Experimental Study of Tool Wear in Milling Multidirectional CFRP Laminates." Materials Science Forum 770 (October 2013): 276–80. http://dx.doi.org/10.4028/www.scientific.net/msf.770.276.
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This study aims to investigate the wear of coated end mills when milling Carbon fiber reinforced polymer (CFRP) composites. Four different types of end mills are used in the milling experiments to identify the influence of tool geometry and material on tool wear. Cutting forces and wear mechanisms of coated mills are also discussed. Through the contrast experiment, diamond coated multitooth router shows the best performance with the smallest cutting force and the least wear extent under the same cutting parameter. The major failure mechanisms of coated tools are breakthrough of coating, coating flaking and abrasive wear of substrate.
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Qin, Yu, Zhe Li, Lin Lin Li, Chun Li Kang, Hong Hai Xue, Fei Peng, and Xue Yu Lin. "Research on the Migration of Naphthalene in the Typical Aquifer Medium in a Petroleum Contaminated Field." Advanced Materials Research 433-440 (January 2012): 6397–402. http://dx.doi.org/10.4028/www.scientific.net/amr.433-440.6397.
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Through the column simulation experiments, this paper researched on the naphthalene migration in the typical aquifer media-gravel sand and coarse sand in a petroleum contaminated field. The research also quantified the retardation of the two medium to the important petroleum component-naphthalene, by giving the retardation parameter after the chlorine breakthrough experiment. The results showed that the migration of naphthalene in the medium is not only influenced by the convection and the dispersion, but also the adsorption and the biodegradation, which is much stronger in the coarse sand than it is in the gravel sand.
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Yue, Ping, Rujie Zhang, James J. Sheng, Gaoming Yu, and Feng Liu. "Study on the Influential Factors of CO2 Storage in Low Permeability Reservoir." Energies 15, no. 1 (January 4, 2022): 344. http://dx.doi.org/10.3390/en15010344.
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As the demands of tight-oil Enhanced Oil Recovery (EOR) and the controlling of anthropogenic carbon emission have become global challenges, Carbon Capture Utilization and Sequestration (CCUS) has been recognized as an effective solution to resolve both needs. However, the influential factors of carbon dioxide (CO2) geological storage in low permeability reservoirs have not been fully studied. Based on core samples from the Huang-3 area of the Ordos Basin, the feasibility and influential factors of geological CO2 sequestration in the Huang-3 area are analyzed through caprock breakthrough tests and a CO2 storage factor experiment. The results indicate that capillary trapping is the key mechanism of the sealing effect by the caprock. With the increase of caprock permeability, the breakthrough pressure and pressure difference decreased rapidly. A good exponential relationship between caprock breakthrough pressure and permeability can be summarized. The minimum breakthrough pressure of CO2 in the caprock of the Huang-3 area is 22 MPa, and the breakthrough pressure gradient is greater than 100 MPa/m. Huang-3 area is suitable for the geological sequestration of CO2, and the risk of CO2 breakthrough in the caprock is small. At the same storage percentage, the recovery factor of crude oil in larger permeability core is higher, and the storage percentage decreases with the increase of recovery factor. It turned out that a low permeability reservoir is easier to store CO2, and the storage percentage of carbon dioxide in the miscible phase is greater than that in the immiscible phase. This study can provide empirical reference for caprock selection and safety evaluation of CO2 geological storage in low permeability reservoirs within Ordos Basin.
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Li, Wen Bo, Yin Gai Jin, Shuang Yin, and Pei Yan Chen. "Electrical Simulation Experiment and the Analysis of Thermal Conductivity of Materials." Advanced Materials Research 989-994 (July 2014): 599–602. http://dx.doi.org/10.4028/www.scientific.net/amr.989-994.599.
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s: Jilin university innovation experiment Electrical Simulation Experiment and the Analysis of Thermal Conductivity of Materials aims to solve the problem of thermocouple measuring tenderness in error. Thermocouple is used to measure temperature when measuring unsteady heat conduction in laboratory. The improved measuring method of unsteady heat conduction puts the breakthrough on the electric simulation method. The text bench is constructed by different shapes of conductive plate which is made of the graphite conductive paint, and voltmeter is refitted by diodes and controlled transformer. Through the test bench, we finished the simulation of unsteady heat conduction under the similar thermal conductive boundary conditions. Finally, the error analysis of experiment and the advantages of electric simulation method are given in this paper.
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Vanderborght, J., and H. Vereecken. "Analyses of locally measured bromide breakthrough curves from a natural gradient tracer experiment at Krauthausen." Journal of Contaminant Hydrology 48, no. 1-2 (March 2001): 23–43. http://dx.doi.org/10.1016/s0169-7722(00)00176-5.
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Wörmeyer, K., and I. Smirnova. "Breakthrough measurements of CO2 through aminofunctionalised aerogel adsorbent at low partial pressure: Experiment and modeling." Microporous and Mesoporous Materials 184 (January 2014): 61–69. http://dx.doi.org/10.1016/j.micromeso.2013.09.032.
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Chang, Hua, Xi-Gang Yuan, Hua Tian, and Ai-Wu Zeng. "Experiment and prediction of breakthrough curves for packed bed adsorption of water vapor on cornmeal." Chemical Engineering and Processing: Process Intensification 45, no. 9 (September 2006): 747–54. http://dx.doi.org/10.1016/j.cep.2006.03.001.
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Vigh, Denes, Jerry Kapoor, Nick Moldoveanu, and Hongyan Li. "Breakthrough acquisition and technologies for subsalt imaging." GEOPHYSICS 76, no. 5 (September 2011): WB41—WB51. http://dx.doi.org/10.1190/geo2010-0399.1.
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The recently introduced method of wide-azimuth data acquisition offers better illumination, noise attenuation, and lower frequencies to more accurately determine a velocity field for imaging. For the field data experiment to demonstrate the technologies, we used a Gulf of Mexico (GOM) wide-azimuth data set that allows us to take advantage of possible low frequencies, relatively large crossline offsets, and increased illumination. The input data was processed through true 3D azimuthal surface-related multiple elimination (SRME) with zero-phasing and debubble. Eliminating the surface-related multiples aids the velocity determination and helps uncover the subsalt sediments at the final imaging stage. After the initial velocity derivation, which was constrained to wells and geology, full-waveform inversion (FWI) was used to further update the velocity field to achieve an enhanced image. The methodology used follows the top-down approach where suprasalt sediment model is developed followed by the top of salt, salt flanks, base of salt, and finished with a limited subsalt update. To approximate the observed data by using an acoustic inversion procedure, the propagator includes effects of attenuation, anisotropy, acquisition source, and receiver depth. The geological environment is salt related, which implies that the observed data is highly elastic, even though it is input to an acoustic full waveform inversion. To use the proper constraints for the inversion, layer-stripping method is used to develop the high-resolution velocity field. The inversion stages were carefully quality controlled through gather displays to ensure the kinematics were honored. We then demonstrated the benefit of the FWI velocity field by comparing the images derived with the traditional ray-based tomographic velocity field versus the velocity field derived by FWI performing reverse time migration to produce these images. Finally, the images were compared at key well locations to evaluate the robustness of the workflow.
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Shelly, Connor D., Ekaterina A. Matrozova, and Victor T. Petrashov. "Resolving thermoelectric “paradox” in superconductors." Science Advances 2, no. 2 (February 2016): e1501250. http://dx.doi.org/10.1126/sciadv.1501250.
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For almost a century, thermoelectricity in superconductors has been one of the most intriguing topics in physics. During its early stages in the 1920s, the mere existence of thermoelectric effects in superconductors was questioned. In 1944, it was demonstrated that the effects may occur in inhomogeneous superconductors. Theoretical breakthrough followed in the 1970s, when the generation of a measurable thermoelectric magnetic flux in superconducting loops was predicted; however, a major crisis developed when experiments showed puzzling discrepancies with the theory. Moreover, different experiments were inconsistent with each other. This led to a stalemate in bringing theory and experiment into agreement. With this work, we resolve this stalemate, thus solving this long-standing “paradox,” and open prospects for exploration of novel thermoelectric phenomena predicted recently.
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Amiri, Mohammad Javad, Jahangir Abedi-koupai, and Saeid Eslamian. "Adsorption of Hg(II) and Pb(II) ions by nanoscale zero valent iron supported on ostrich bone ash in a fixed-bed column system." Water Science and Technology 76, no. 3 (May 4, 2017): 671–82. http://dx.doi.org/10.2166/wst.2017.252.
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In this research, ostrich bone ash (OBA) was modified with nanoscale zerovalent iron (nZVI) particles and applied as a novel composite adsorbent (OBA/nZVI) for dynamic adsorption/reduction of Hg(II) and Pb(II) ions in a fixed-bed column system. Entrapment of nZVI in OBA beads barricades the particles from oxidation and aggregation. The dynamic behavior of metal ions removal by OBA/nZVI was assessed as a function of inlet flow rates, bed height, initial pollutants concentration and pH. The synthesized OBA/nZVI composite was characterized by several physicochemical techniques. Increase in pH and bed height and decrease in flow rates and initial metal concentration resulted in delay of breakthrough time. OBA breakthrough profile is sharper than the OBA/nZVI breakthrough curve for both metal ions and the breakthrough times increase in the order OBA/nZVI-Hg(II) > OBA/nZVI-Pb(II) > OBA-Pb(II) > OBA-Hg(II). Based on the experiment results, redox reaction is expected to occur to a certain extent, as the standard reduction potentials of Hg(II) and Pb(II) are more than that of Fe(II). From a practical point of view, the OBA/nZVI could be applied as a material to remove Hg(II) and Pb(II) ions from natural surface and ground water with a pH value of 5–9.
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Zhang, Ge, Yuesuo Yang, Ying Lu, Yu Chen, Wenbo Li, and Siyuan Wang. "Effect of Heavy Metal Ions on Steroid Estrogen Removal and Transport in SAT Using DLLME as a Detection Method of Steroid Estrogen." Water 12, no. 2 (February 21, 2020): 589. http://dx.doi.org/10.3390/w12020589.
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Environmental endocrine-disrupting chemicals have become a global environmental problem, and the distribution, transport, and fate of estrogens in soil and water environments closely relate to human and ecological health as well as to the remediation scheme design. A new micro-extraction technique termed dispersive liquid–liquid micro-extraction (DLLME) combined with high-performance liquid chromatography with fluorescence detector (HPLC-FLD) was developed for the determination of the concentration of steroid estrogens in water samples. The detection limits of HPLC-FLD and DLLME-HPLC/FLD were 0.68–1.73 μg L−1 and 7.16–69.22 ng L−1, respectively. Based on this method, the isothermal adsorption of 17β-E2 on sand and a breakthrough experiment of 17β-E2 and Cu2+ in a soil aquifer treatment (SAT) system were studied. The 17β-E2 adsorption capacity of sand in 17β-E2 solution was detected to be larger than that in a mixed solution of 17β-E2 and Cu(NO3)2 solution, and the breakthrough curves of 17β-E2 and Cu2+ in the mixed solution shifted forward in sand column experiments. Both suggested that the competitive adsorption of 17β-E2 and Cu2+ in the mixed solution might occur on the surface of the sand. In the process of the removal of 17β-E2 in wastewater by SAT, the existence of Cu2+ slightly inhibited the adsorption of 17β-E2 and accelerated the breakthrough of 17β-E2. These results ought to be a warning for SAT application for 17β-E2 removal in water where heavy metals coexist.
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Cesarian, Dwiky Pobri. "Study of Low-Salinity Waterflooding for Sandstone Reservoir." IJIS Edu : Indonesian Journal of Integrated Science Education 1, no. 1 (January 30, 2019): 85. http://dx.doi.org/10.29300/ijisedu.v1i1.1642.
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Recent studies showed that salinity concentration of the injected water is more important factor rather than the amount of water injected. The objectives of this study are to analyse the effect of salinity and its behaviour in waterflooding and calculating the recovery factor of the oil produced in sandtone reservoir condition. This study focuses on analysing the effect of salinity to its recovery factor, relative permeability, breakthrough time and water cut of the oil-water system. Laboratory experiment had been carried out to determine the recovery factor by using sandstone core with the dimension length and diameter of 3 in and 1.5 in, respectively. Sodium Chloride (NaCl) was used to control the salinity concentration in waterflooding with range of 1,000 ppm to 14,000 ppm. The experiment was run with constant flow rate, pressure and temperature. In this experiment, deionized water with varied salinity and paraffin oil were used to perform the waterflooding procedure. Based on the results obtained, the highest total oil recovery by waterflooding was 57.8% with 4,000 ppm as the optimum salinity, which is 14.6% higher than oil recovered by 14,000 ppm. The results also showed the change in end-point value of relative permeability. It also showed that water cut tend to increase as the salinity increase, while breakthrough time tend to decrease as the salinity increase.
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Dizer, H., G. Grützmacher, H. Bartel, H. B. Wiese, R. Szewzyk, and J. M. López-Pila. "Contribution of the colmation layer to the elimination of coliphages by slow sand filtration." Water Science and Technology 50, no. 2 (July 1, 2004): 211–14. http://dx.doi.org/10.2166/wst.2004.0127.
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River bank or slow sand filtration is a major procedure for processing surface water to drinking water in central europe. In order to model the performance of river bank and slow sand filtration plants, we are studying the different mechanisms by which the elimination of pathogens is realized. An important question concerning the mode of action of slow sand filters and river bank filtration units is the role of the colmation layer or “schmutzdecke” on the elimination of human pathogens. The schmutzdecke is an organic layer which develops at the surface of the sand filter short after the onset of operation. We have inoculated a pilot plant for slow sand filtration with coliphages and determined their rate of breakthrough and their final elimination. In the first experiment, with a colmation layer still missing, the breakthrough of the coliphages in the 80 cm mighty sandy bed amounted to ca. 40%. In contrast, less than 1% of coliphages escaped from the filter as the same experiment was repeated two months later, when a substantial colmation layer had developed. Our preliminary conclusions are that the colmation layer is extremely efficient in eliminating of viruses.
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Sui, Fu Dong, Guang Sheng Cao, Chun Bao Ma, and Xiao Ma. "Study on Water Plugging Technology by Emulsified Viscous Oil in Block Jin16." Applied Mechanics and Materials 535 (February 2014): 432–35. http://dx.doi.org/10.4028/www.scientific.net/amm.535.432.
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Water plugging by emulsified viscous oil s a kind of advanced technology with high selectivity, which causes little damage to reservoir and brings high economic benefit for oil wells. Through a series of simulation experiments in the laboratory, the effects of temperature, water ratio, salinity, the emulsifier concentration, the viscosity of crude oil on the emulsion viscosity is studied, also long-term stability of emulsion. The following analysis of the experimental data makes the main factor affecting water plugging by emulsified heavy oil clear. By the Indoor core simulation experiment, this paper determines changes of pressure, recovery and breakthrough pressure and studies injection capacity of emulsified crude oil and sealing performance to ensure reasonable injection parameters.
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Chen, Xuelei. "Probing dark energy and primordial non-Gaussianity with the 21cm line observations." International Journal of Modern Physics A 30, no. 28n29 (October 20, 2015): 1545011. http://dx.doi.org/10.1142/s0217751x15450116.
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In this paper I review some recent progress in the studies on redshifted 21cm line observations. The 21cm line have long been an important radio spectral line in astronomical observations, but so far its observation is limited to low redshifts, due to the difficulty in detecting this line at high or mid redshifts. However, more sophisticated data processing method are being developed, and a number of experiments are being carried out. Once this breakthrough is made, the observation may provide an wealth of information which would be useful in probing the nature of dark energy, and searching for primordial non-Gaussianity (PNG). I will also describe the status of the Tianlai experiment as of the summer of 2015.
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Talukder, Ria, Anas Skalli, Xavier Porte, and Daniel Brunner. "Computation and implementation of large scalable Spiking Neural Network." EPJ Web of Conferences 287 (2023): 13006. http://dx.doi.org/10.1051/epjconf/202328713006.
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Photonic neural networks are a highly sought-after area of research due to their potential for high-performance complex computing. Unlike artificial neural networks, which use simple nonlinear maps, biological neurons transmit information and perform computations through spikes that depend on spike time and/or rate. Through comprehensive studies and experiments, a strong foundation has been laid for the development of photonic neural networks. We have recently developed a large-scale spiking neural network, which serves as a proof-of-concept experiment for novel bio-inspired learning concepts. This breakthrough is significant because it demonstrates the potential of using photonic neural networks for advanced computing and highlights the importance of incorporating biological principles into artificial intelligence research.
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Zhang, Xiaoling, Xincong Liu, Zhuo Zhang, and Ziwei Chen. "Removal of phosphate from aqueous solution by chitosan coated and lanthanum loaded biochar derived from urban dewatered sewage sludge: adsorption mechanism and application to lab-scale columns." Water Science and Technology 84, no. 12 (November 9, 2021): 3891–906. http://dx.doi.org/10.2166/wst.2021.485.
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Abstract A lanthanum modified sludge biochar chitosan (La-SBC-CS) microsphere was successfully synthesized by dropping sludge biochar (BC) and chitosan into a lanthanum chloride solution. Batch adsorption experiments were conducted to investigate the adsorption kinetics and isotherm. Application of continuous phosphate removal was achieved via lab-scale column reactors. The phosphate adsorption equilibrium data of the La-SBC-CS fitted well with the Freundlich isotherm, with a maximum adsorption amount of 81.54 mg p/g at 25 °C. Characterization of the adsorbent using scanning electron microscopy analysis (SEM), X-ray energy spectrum analysis (EDS), X-ray diffraction analysis (XRD) and Fourier infrared analysis (FTIR) techniques suggested that the possible adsorption mechanisms were electrostatic interaction, ligand exchange and complexation. The La-SBC-CS kept 76.37% phosphate removal efficiency after eight recycles. The results of continuous column reactor experiment demonstrated that the breakthrough time increased with an increase in adsorbent filling height, while it decreased with an increase in initial phosphate concentration or flow velocity. The Yoon model was applied to the continuous experimental data to predict breakthrough curves and determined the characteristic adsorption parameters for process design. This study indicated the potential for the practical application of La-SBC-CS in phosphate removal from wastewater.
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Nguyen, Huy Van, and Morihiro Maeda. "Removal of phosphorus from water by using volcanic ash soil (VAS): batch and column experiments." Water Science and Technology 74, no. 6 (June 24, 2016): 1326–34. http://dx.doi.org/10.2166/wst.2016.297.
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Using low-cost and naturally available materials is considered an optimal adsorbent for removing phosphorus (P) from water due to its simplicity and economic efficiency. This study examined the removal of P from water using volcanic ash soil (VAS) by batch and column experiments. The maximum adsorption capacity of P was 2.94 mg g−1, estimated from the batch experiment according to a Langmuir isotherm. The column study showed a higher adsorption capacity of 5.57 mg g−1. The breakthrough curve showed that influent water containing 2 mg L−1 P was completely purified by VAS within 1,230 pore volumes (PV). The breakthrough and saturation points of the curves were 3,100 PV and 14,875 PV, respectively. After an adsorption column was loaded with 20,508 PV, a regeneration procedure was developed to determine whether an ion exchange of P with chloride occurred or adsorbed P in the columns could be eluted. Approximately 20% of P was recovered from columns by desorption tests, regardless of NaCl solution or deionized water. Specific surface area and mineral concentrations are both important characteristics that improve the adsorption capacity of VAS. The present study suggests that VAS is a promising adsorbent to remove P in water.
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Sun, Liang, Baozhu Li, Hanqiao Jiang, Yong Li, and Yuwei Jiao. "An Injectivity Evaluation Model of Polymer Flooding in Offshore Multilayer Reservoir." Energies 12, no. 8 (April 15, 2019): 1444. http://dx.doi.org/10.3390/en12081444.
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Good polymer flood performance evaluation requires an understanding of polymer injectivity. Offshore reservoirs are characterized by unfavorable water–oil mobility ratios, strong heterogeneity, and multilayer production, which collectively contribute to unique challenges. Accordingly, this article presents a semi-analytical model for the evaluation of commingled and zonal injectivity in the entire development phase, which consists of primary water flooding, secondary polymer flooding, and subsequent water flooding. First, we define four flow regions with unique saturation profiles in order to accurately describe the fluid dynamic characteristics between the injector and the producer. Second, the frontal advance equation of polymer flooding is built up based on the theory of polymer–oil fractional flow. The fluid saturation distribution and the injection–production pressure difference are determined with the method of equivalent seepage resistance. Then, the zonal flow rate is obtained by considering the interlayer heterogeneity, and the semi-analytical model for calculating polymer injectivity in a multilayer reservoir is established. The laboratory experiment data verify the reliability of the proposed model. The results indicate the following. (1) The commingled injectivity decreases significantly before polymer breakthrough and increases steadily after polymer breakthrough. The change law of zonal injectivity is consistent with that of commingled injectivity. Due to the influence of interlayer heterogeneity, the quantitative indexes of the zonal flow rate and injection performance are different. The injectivity of the high-permeability layer is better than that of the low-permeability layer. (2) The higher the injection rate and the lower the polymer concentration, the better the injectivity is before polymer breakthrough. An earlier injection time, lower injection rate, larger polymer injection volume, and lower polymer concentration will improve the injectivity after polymer breakthrough. The polymer breakthrough time is a significant indicator in polymer flooding optimization. This study has provided a quick and reasonable model of injectivity evaluation for offshore multilayer reservoirs.
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Persson, Magnus, and Ronny Berndtsson. "Transect Scale Solute Transport Measured by Time Domain Reflectometry." Hydrology Research 33, no. 2-3 (April 1, 2002): 145–64. http://dx.doi.org/10.2166/nh.2002.0020.
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Two quasi steady-state solute transport experiments were carried out in a loamy sand under field conditions. The flux was 40 mm/d in experiment 1 and 18.7 mm/d in experiment 2. Both water content (θ) and resident concentration (Cr) measurements were taken using 64 time domain reflectometry probes at depths ranging from 0.05 to 0.90 m. The Cr measurement was calibrated in situ for each probe location in the field. The convective dispersive equation (CDE) and convective lognormal transfer function (CLT) models were fitted to the breakthrough curves (BTCs). The results indicated fingered flow, which has been shown to exist in previous studies of this soil. The finger width was larger in experiment 1 leading to smaller horizontal heterogeneity and a relatively smaller solute transport velocity. The location of the fingers was consistent between the two experiments resulting in a high correlation between the velocity and mass balance fields. Mass balance calculations showed that the solute mass integrated over depth one day after the solute application was larger than the mass balance for the entire experiment (integrated over time). The probable reason being that solutes were transported out of the measurement volume by horizontal flow across the Ap/E horizon boundary. The investigation of the transport parameters revealed that both the CDE and CLT models could be successfully used to predict most individual BTCs. Horizontally averaged global CDE and CLT models were also fitted to the data. Global solute transport was better modeled with the CDE model in experiment 1, while in experiment 2, the CLT model was better. This study clearly shows the applicability of using TDR with the in situ calibration technique in field experiments with varying water content.
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He, Zhao Ju, Yan Qin Lu, Li Zhu, and Feng Mei Qiao. "Phosphorus Dynamic Adsorption from Wastewater by Iron-Oxide-Coated-Zeolite." Applied Mechanics and Materials 522-524 (February 2014): 660–64. http://dx.doi.org/10.4028/www.scientific.net/amm.522-524.660.
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In this paper, Iron-Oxide-Coated-Zeolite has been prepared by using natural zeolite and ferric nitrate. The absorbing effect of IOCZ on phosphorus is also investigated, including the filler height, the flow rate and initial phosphorus concentration on breakthrough curve were studied. The results show that IOCZ as an adsorbent can effectively remove the phosphorus from the wastewater. When the filler height and the initial phosphorus concentration increased, the adsorption effect increased and the breakthrough time reduced. The best filler height is 30cm. The higher the initial phosphorus concentration is, the less the processing water is. Column experiment was used for advanced treatment and it can process substantial wastewater, and then makes the effluent phosphorus concentration meet the national emission standards. When the regenerated solution was trickled into the solution about 5min, almost all of the phosphorus separated from the IOCZ.
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El Zayat, Mohamed, and Edward Smith. "Modeling of heavy metals removal from aqueous solution using activated carbon produced from cotton stalk." Water Science and Technology 67, no. 7 (April 1, 2013): 1612–19. http://dx.doi.org/10.2166/wst.2013.037.
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Activated carbon produced from cotton stalks was examined for the removal of heavy metal contaminants. Adsorption studies in completely mixed batch reactors were used to generate equilibrium pH adsorption edges. Continuous flow experiments using the activated carbon in fixed beds were conducted to determine heavy metal breakthrough versus bed volumes treated. At given pH value in the range 5–7, the adsorption capacity was similar for copper and lead and clearly greater than for cadmium. A surface titration experiment indicated negative surface charge of the activated carbon at pH > 6, meaning that electrostatic attraction of the divalent heavy metals can occur below the pH required for precipitation. Substantive metal removal below the pH of zero charge might be due to surface complexation. Accordingly, a surface complexation model approach that utilizes an electrostatic term in the double-layer description was used to estimate equilibrium constants for the protolysis interactions of the activated carbon surface as well as equilibria between background ions used to establish ionic strength and the sorbent surface. Pb(II) adsorption edges were best modeled using inner-layer surface complexation of Pb2+, while Cd(II) and Cu(II) data were best fit by outer-layer complexes with Me2+. The full set of equilibrium constants were used as input in a dual-rate dynamic model to simulate the breakthrough curves of the target metals (Pb, Cu and Cd) from fixed bed experiments and to estimate external (or film) diffusion and internal (surface) diffusion coefficients.
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Soto-Rios, Paula Cecilia, Kazunori Nakano, Marco Leon-Romero, Yoshio Aikawa, Shigeyuki Arai, and Osamu Nishimura. "Differences in the removal mechanisms of Undaria pinnatifida and Phragmites australis as biomaterials for lead removal." Water Science and Technology 72, no. 7 (June 29, 2015): 1226–33. http://dx.doi.org/10.2166/wst.2015.334.
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This study offers the opportunity to utilize Undaria pinnatifida and Phragmites australis to remove lead from water in permeable reactive barrier (PRB) technology. Its efficacy was tested using batch experiments and PRB column systems. From the batch experiment results, a higher adsorption capacity was observed for Undaria pinnatifida. Nevertheless, Phragmites australis in the column system efficiently removed lead and the breakthrough occurred at the same time for both biomaterials. To dissipate this difference, a sequential extraction for metal speciation analysis was used for both columns. The results have shown that each biomaterial has a dominant mechanism. Phragmites australis removed lead by physical adsorption, whereas Undaria pinnatifida showed a higher tendency to bind lead due to organic matter, primary and secondary minerals.
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Chebanov, Dmitrii K., Vsevolod A. Misyurin, and Nadezhda S. Tatevosova. "Abstract A014: Deep learning-driven drug discovery: A breakthrough algorithm and its implication in lung cancer therapy development." Molecular Cancer Therapeutics 22, no. 12_Supplement (December 1, 2023): A014. http://dx.doi.org/10.1158/1535-7163.targ-23-a014.
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Abstract We have developed an algorithm and implemented it in a software platform for the purpose of developing new anti-tumor drugs in the form of small molecules. In this study, we focused on generating molecules specifically for the treatment of lung cancer patients. To begin with, we employed deep learning (DL) techniques to evaluate the genes associated with poor clinical outcomes in lung cancer patients. By utilizing generative adversarial neural networks (GAN), we acquired additional patient data. The results of each experiment were presented as a list of genes ordered by their impact on the desired effect. We then intersected the lists of genes obtained from experiments with overall survival (OS) and progression-free interval (PFI) data. This allowed us to identify a set of genes whose expression was correlated with poor prognosis. In order to enhance the precision, we trained another DL model to distinguish between normal and tumor tissue based on gene expression. By doing so, we were able to identify the smaller set of genes that could be targeted. Subsequently, we developed a module that predicts the interactions between inhibitors and proteins. This involved representing protein amino acid sequences and chemical compound formulas in vector form, and a virtual screening of the Pubchem database. The implementation of the Drug-protein interactions module resulted in a dataset of 118,379 pairs, including 19,250 pairs describing compounds bound to proteins, and 99,129 precedents describing non-bound ones. DLwas applied, yielding a ROC-AUC of 0.86. Following the search for candidate molecules, we obtained 160,000 pairs with a predicted interaction probability above 0.99, as well as 2,921 pairs with probability of 1.0. Additionally, we created a DL-based module to predict the IC50 values in cell line experiments. Virtual pre-clinical trials were conducted using the selected inhibitors to identify relevant cell lines for subsequent laboratory experiments. Through this process, we obtained formulas for several molecules that demonstrated predicted binding to specific proteins. During the cell experiment emulation, our feature importance algorithm selected 129 genes. For the cell experiment emulation stage, we specifically chose interactions with a probability of at least 0.9. We prioritized molecules that acted on the minimum number of cell lines with a higher probability, thus ensuring higher specificity. Ultimately, we selected 5 small molecules as potential candidates, as well as certain cell lines for their validation. The NLP technologies utilized in this study demonstrated their effectiveness in processing tens of thousands of articles. The pipeline of methods presented in this paper lays the groundwork for automated AI-driven drug discovery. We have showcased the application of modern machine learning methods, particularly DL, as well as the methods used to prepare the initial data for the learning algorithms. The performance of these methods has been validated through cross-validation using data from publicly available sources. Citation Format: Dmitrii K Chebanov, Vsevolod A Misyurin, Nadezhda S Tatevosova. Deep learning-driven drug discovery: A breakthrough algorithm and its implication in lung cancer therapy development [abstract]. In: Proceedings of the AACR-NCI-EORTC Virtual International Conference on Molecular Targets and Cancer Therapeutics; 2023 Oct 11-15; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Ther 2023;22(12 Suppl):Abstract nr A014.
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Katzer, Frank, Daniel Ngugi, Christian Schnier, Alan R. Walker, and Declan J. McKeever. "Influence of Host Immunity on Parasite Diversity in Theileria parva." Infection and Immunity 75, no. 10 (July 16, 2007): 4909–16. http://dx.doi.org/10.1128/iai.00710-07.
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ABSTRACT We examined the influence of host immunity on the genotypic diversity of the intracellular transforming cattle parasite Theileria parva. By tracking the emergence of discrete parasite genotypes in an animal challenged with a bulk stabilate following immunization with its major component clone, we observed a profound modulation of genotypic frequencies in the breakthrough schizont population. In particular, no incidences of the immunizing clone were observed and a progressive decline was apparent in the relatedness of breakthrough genotypes to it. These observations were reflected in the genotypic profile of transmissible parasite stages that emerged in the erythrocyte fraction of the animal and in parasite progeny generated by tick pickup. In a separate experiment, genotypic profiles of breakthrough parasite populations were observed to vary between unrelated immune animals selected on the basis of the major histocompatibility complex (MHC) class I phenotype, a known determinant of the specificity of the immune response. Furthermore, immunization and challenge of calves with molecularly distinct but cross-protective parasite populations revealed that infection results in transmissible erythrocyte forms in spite of a protective immune response. These observations suggest that immunity does not prevent transmission of challenge parasites and that its impact on the parasite at a population level is influenced by herd MHC diversity.
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Carey, PL, RG Mclaren, KC Cameron, and JR Sedcole. "Leaching of copper, chromium, and arsenic through some free-draining New Zealand soils." Soil Research 34, no. 4 (1996): 583. http://dx.doi.org/10.1071/sr9960583.
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Concentrated toxic solutions of copper, chromium, and arsenic (CCA) are used extensively in the New Zealand timber preservation industry. A 2% w/v solution containing cupric, dichromate, and arsenate ions was leached through undisturbed soil monolith lysimeters containing the surface and subsurface horizons of 2 free-draining New Zealand soils. The resulting breakthrough curves were successfully modelled using the Gompertz equation for biomass growth. Differences between soil horizons in the fitted Gompertz parameter values were related to differences in soil physical and chemical properties affecting leaching. Results were compared to those from a previous study investigating pulse leaching of a concentrated CCA solution of similar ion ratio using the same soils. Generally, solution leaching produced breakthrough curves influenced more by the soil's physical structure and less by kinetic processes (i.e. sorption and diffusion). This was in part due to the high metal concentrations of the CCA solution and the decreased contact time between soil and solute in the solution leaching experiment. The relative ease of solute ion breakthrough increased in the order copper < arsenate < dichromate. The study suggests that further research is required to assess management implications for spills of these heavy metal ions to soils to prevent leaching or runoff to ground and surface water.
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Khanh, Nguyen Hong, and Nguyen Viet Hoang. "Adsorption process on fixed bed column in rich organic wastewater treatment experimental studies and numerical simulation." Vietnam Journal of Mechanics 28, no. 1 (April 17, 2006): 28–34. http://dx.doi.org/10.15625/0866-7136/28/1/5476.
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None axially dispersed plug flow model (NADPF) was applied to simulate adsorption process on fixed bed column. To determine model input parameters and verify the model, isotherm curve, solid diffusion coefficient (\(D_s\)) and breakthrough curve have been determined from experiment. Activated carbon SWW 210&220 was selected as the main adsorbent for research. Wastewater of Minhkhai Textile Company is the sample used in experiment study. According to isotherm function, textile wastewater is poorly adsorbed into SWW210&220. Kinetic data also show that diffusion step of textile wastewater is very slow (DS ~ 1.31*\(10^{-13}\) m\(^2\)/s). With textile wastewater, NADPF model can be used to simulate adsorption process.
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Beji, Rihab, Wissem Hamdi, Aida Kesraoui, and Mongi Seffen. "Adsorption of phosphorus by alkaline Tunisian soil in a fixed bed column." Water Science and Technology 78, no. 4 (July 31, 2018): 751–63. http://dx.doi.org/10.2166/wst.2018.341.
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Abstract The present study evaluates the phosphorus (P) adsorption by alkaline soil in fixed bed column mode operation. The effects of flow rate, bed height, and initial P concentration on breakthrough curves were evaluated. Data confirmed that both the breakthrough and exhaustion time increased in parallel with the rise in bed height and the decline in flow rate and initial P concentration. The adsorption capacity was observed to increase with decreasing flow rate and bed height and increasing initial concentration. Moreover, continuous adsorption experiments were conducted using three salts (NaCl, KCl and CaCl2) with the same concentration (0.01 M) to investigate the P adsorption behavior in saline conditions. The results showed that all three salts improve the P adsorption in the soil column. Consequently, the bed performance was significantly enhanced with salts addition. The maximum adsorption capacity of 13.47 mg g−1 for P, 16.13 mg g−1 for P-NaCl, 22.10 mg g−1 for P-KCl, 30.05 mg g−1 for P-CaCl2 was attained at an initial influent concentration of 300 mg g−1, bed height of 22 cm, and flow rate of 10 mL min−1. TheCaCl2 addition was therefore the most effective in increasing P adsorption. Thomas, Yoon-Nelson and Clark models were applied to experimental results to forecast the breakthrough curves by nonlinear regression analysis. Meanwhile, the bed depth service time model was employed to examine the effective model parameters in scaling up the process using linear regression analysis. The values of correlation coefficient (R2) and the sum of squared error evidenced that the Thomas model is the most appropriate model to fit the experimental data. The reusability experiment showed that the adsorbent material still had high P adsorption capacity, and tolerable desorption efficiency.