scholarly journals Removal of ethylene oxide from waste gases by absorption

2011 ◽  
Vol 65 (4) ◽  
pp. 389-395 ◽  
Author(s):  
Zorana Arsenijevic ◽  
Zeljko Grbavcic ◽  
Bosko Grbic ◽  
Nenad Radic ◽  
Radmila Garic-Grulovic ◽  
...  
Keyword(s):  
Ethylene Oxide ◽  
Contact Time ◽  
Organic Pollutant ◽  
Experimental Studies ◽  
Industrial Plant ◽  
Emission Sources ◽  
Crucial Importance ◽  
In Series ◽  
Time Part ◽  
High Degree

Ethylene oxide (EtO) is an organic compound, which is used as starting material in the production of polymers and as sterilizing agent for thermolabile materials. Although ethylene oxide is not common as an organic pollutant, its removal from numerous emission sources (e.g. ethylene oxide production plants or food and pharmaceutical sterilizing units) is of the crucial importance because of its mutagenic, teratogenic and cancerogenic effect on human health. The objective of this paper is the experimental investigation of ethylene oxide (EtO) absorption in diluted aqueous solution of sulfuric acid in order to evaluate the applicability of this procedure as well as to obtain project parameters for industrial plant realization. It was found that absorption is suitable as the fist step in the purification treatment of high EtO concentrations in the emission gases. According to the literature data, the basic parameter that defines the scrubber efficiency is the contact time, i.e. the ratio of packing height in scrubber and velocity of gas mixture. To investigate the characteristics of wet treatment in a broad range of contact time, part of experimental studies were conducted in the system with two and with three scrubbers in series. The obtained experimental results show that the high degree of EtO removal can be achieved (>98%) when the contact time is sufficiently long (about 25 s). The process is effective until the concentration of formed glycol in the solution reaches value of about 20%. The process is safe and there is no danger of ignition and explosion of air and EtO mixture, although at the entrance to the scrubber EtO concentrations are significantly above the lower explosive limit.

A possibility of using nickel concentrate, obtained as a result of hydrometallurgical enrichment of manganese-containing raw materials, at steel alloying

2020 ◽  
Vol 76 (7) ◽  
pp. 709-715
Author(s):  
O. Yu. Kichigina
Keyword(s):  
Raw Materials ◽  
Experimental Studies ◽  
Selective Extraction ◽  
Technological Parameters ◽  
Nickel Iron ◽  
Nickel Recovery ◽  
Nickel Concentrate ◽  
Steel Alloying ◽  
High Degree ◽  
Comprehensive Processing

At production of stainless steel expensive alloying elements, containing nickel, are used. To decrease the steel cost, substitution of nickel during steel alloying process by its oxides is an actual task. Results of analysis of thermodynamic and experimental studies of nickel reducing from its oxide presented, as well as methods of nickel oxide obtaining at manganese bearing complex raw materials enrichment and practice of its application during steel alloying. Technology of comprehensive processing of complex manganese-containing raw materials considered, including leaching and selective extraction out of the solution valuable components: manganese, nickel, iron, cobalt and copper. Based on theoretical and experiment studies, a possibility of substitution of metal nickel by concentrates, obtained as a result of hydrometallurgical enrichment, was confirmed. Optimal technological parameters, ensuring high degree of nickel recovery out of the initial raw materials were determined. It was established, that for direct steel alloying it is reasonable to add into the charge pellets, consisting of nickel concentrate and coke fines, that enables to reach the through nickel recovery at a level of 90%. The proposed method of alloying steel by nickel gives a possibility to decrease considerably steel cost at the expense of application of nickel concentrate, obtained out of tails of hydrometallurgical enrichment of manganese-bearing raw materials, which is much cheaper comparing with the metal nickel.

scholarly journals A deep learning method for automatic segmentation of the bony orbit in MRI and CT images

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Jared Hamwood ◽  
Beat Schmutz ◽  
Michael J. Collins ◽  
Mark C. Allenby ◽  
David Alonso-Caneiro
Keyword(s):  
Deep Learning ◽  
Human Performance ◽  
Automatic Segmentation ◽  
Ct Images ◽  
Human Observer ◽  
In Series ◽  
Magnetic Resonance Imaging Mri ◽  
High Degree ◽  
Orbital Region ◽  
Ct And Mri

AbstractThis paper proposes a fully automatic method to segment the inner boundary of the bony orbit in two different image modalities: magnetic resonance imaging (MRI) and computed tomography (CT). The method, based on a deep learning architecture, uses two fully convolutional neural networks in series followed by a graph-search method to generate a boundary for the orbit. When compared to human performance for segmentation of both CT and MRI data, the proposed method achieves high Dice coefficients on both orbit and background, with scores of 0.813 and 0.975 in CT images and 0.930 and 0.995 in MRI images, showing a high degree of agreement with a manual segmentation by a human expert. Given the volumetric characteristics of these imaging modalities and the complexity and time-consuming nature of the segmentation of the orbital region in the human skull, it is often impractical to manually segment these images. Thus, the proposed method provides a valid clinical and research tool that performs similarly to the human observer.

Theoretical and Experimental Studies of Sulfur and Boron Distribution between the Slag of the CaO-SiO2-B2O3-MgO-Al2O3 System and the Metal

2021 ◽  
Vol 410 ◽  
pp. 287-292
Author(s):  
Anatolij A. Babenko ◽  
Leonid A. Smirnov ◽  
Alena G. Upolovnikova
Keyword(s):  
Distribution Coefficient ◽  
Thermodynamic Modeling ◽  
Experimental Studies ◽  
Oxide System ◽  
Slag Basicity ◽  
Interphase Distribution ◽  
Desulfurization Process ◽  
Simplex Lattice ◽  
High Degree ◽  
Effect Of The Composition

The equilibrium interfacial distribution of sulfur and boron was estimated using the HSC 6.1 Chemistry software package (Outokumpu) and the simplex-lattice planning method. Adequate mathematical models have been constructed in the form of III degree polynomial, which describe the effect of the composition of the studied oxide system on the equilibrium distribution of sulfur and boron between the slag and the metal. Generalization of the results of experimental studies and thermodynamic modeling made it possible to obtain new data on the influence of the basicity and content of B2O3 in the slag of the CaO-SiO2-B2O3-MgO-Al2O3 system on the interphase distribution of sulfur and boron. It was found that in the range of boron oxide concentration of 1.0-10%, an increase in slag basicity from 2 to 5 at 1600°C leads to an increase in the sulfur distribution coefficient from 1 to 20 and, as a consequence, a decrease in the sulfur content in the metal from 0.02 to 0.0014 %, i.e. an increase in slag basicity favorably affects the development of the metal desulfurization process. An increase in the B2O3 content from 2.0 to 10.0% in slags formed in the region of moderate basicity, not exceeding 2-3, is accompanied at 1600°C by a decrease in the boron interphase distribution coefficient from 450 to 150 and an increase in the boron concentration in the metal from 0.006 to 0.021 %, which indicates the progress of boron reduction from slag to metal. The shift of the formed slags to the area of ​​increased basicity up to 5.0 shows a high degree of boron reduction from slag to metal. The results of the laboratory experiment confirmed the results of thermodynamic modeling.

Main approaches to treatment of hypoxia in acute respiratory distress syndrome, bacterial and viral pneumonia (part III)

2021 ◽  
pp. 38-55
Author(s):  
A. V. Vlasenko ◽  
E. A. Evdokimov ◽  
E. P. Rodionov
Keyword(s):  
Respiratory Failure ◽  
Distress Syndrome ◽  
Experimental Studies ◽  
Viral Pneumonia ◽  
Medical Technologies ◽  
Clinical Observations ◽  
Wide Range ◽  
Prevention And Treatment ◽  
High Degree

The paper summarizes data on modern approaches to the diagnosis, prevention and treatment of severe acute parenchymal respiratory failure of various origins, including ARDS due to bacterial viral pneumonia. The work is based on the data of modern well-organized studies, analysis of international clinical guidelines with a high degree of evidence, as well as the results of our own long-term experimental studies and clinical observations of the treatment of patients with ARDS of various origins, including viral pneumonia of 2009, 2016, 2020. Scientifically grounded algorithms for prevention, differential diagnosis and personalized therapy of severe acute respiratory failure using innovative medical technologies and a wide range of respiratory and adjuvant treatment methods have been formulated. The authors tried to adapt as much as possible the existing current recommendations for the daily clinical practice of anesthesiologists and resuscitators.

Modeling Cyclic Variability in Spark-Assisted HCCI

2008 ◽  
Vol 130 (5) ◽  
Author(s):  
C. Stuart Daw ◽  
K. Dean Edwards ◽  
Robert M. Wagner ◽  
Johney B. Green
Keyword(s):  
Control Strategies ◽  
Experimental Studies ◽  
Mode Switching ◽  
Load Range ◽  
Gasoline Engines ◽  
Cyclic Variability ◽  
Hcci Combustion ◽  
Quantitative Understanding ◽  
Low Dimensional ◽  
High Degree

Spark assist appears to offer considerable potential for increasing the speed and load range over which homogeneous charge compression ignition (HCCI) is possible in gasoline engines. Numerous experimental studies of the transition between conventional spark-ignited (SI) propagating-flame combustion and HCCI combustion in gasoline engines with spark assist have demonstrated a high degree of deterministic coupling between successive combustion events. Analysis of this coupling suggests that the transition between SI and HCCI can be described as a sequence of bifurcations in a low-dimensional dynamic map. In this paper, we describe methods for utilizing the deterministic relationship between cycles to extract global kinetic rate parameters that can be used to discriminate multiple distinct combustion states and develop a more quantitative understanding of the SI-HCCI transition. We demonstrate the application of these methods for indolene-containing fuels and point out an apparent HCCI mode switching not previously reported. Our results have specific implications for developing dynamic combustion models and feedback control strategies that utilize spark assist to expand the operating range of HCCI combustion.

scholarly journals EVALUATION OF HYDROPHILIC GLOBULES WITH SODIUM ALGINATE CONTAINING A LACTIC ACID– CHITOSAN COMPLEX

2021 ◽  
Vol 26 ◽  
pp. 170-177
Author(s):  
Katarzyna Małolepsza-Jarmołowska ◽  
Keyword(s):  
Lactic Acid ◽  
Rheological Properties ◽  
Sodium Alginate ◽  
Contact Time ◽  
Experimental Studies ◽  
Vaginal Mucosa

An important issue in the treatment of vaginitis is the amount of time the drug remains on the vaginal mucosa. If the contact time is too short, the drug cannot work effectively to ensure the correct pH in the vaginal environment. This study evaluated formulations of globules containing sodium alginate, lactic acid and chitosan with different pH and rheological properties. The experimental studies revealed that it is possible to produce a preparation with optimal pharmaceutical and application properties. The use of an appropriate ratio of lactic acid to chitosan in the complex and the appropriate concentration of sodium alginate produces a preparation with excellent properties to coat the surface of the vaginal mucosa.

scholarly journals Photocatalytic Efficiency of TiO2-Biomass Loaded Mixture for Wastewater Treatment

2018 ◽  
Vol 2018 ◽  
pp. 1-14 ◽  
Author(s):  
Devagi Kanakaraju ◽  
Soon Pang Wong
Keyword(s):  
Wastewater Treatment ◽  
Contact Time ◽  
Oxygen Demand ◽  
Cod Removal ◽  
Wastewater Effluent ◽  
Photocatalytic Efficiency ◽  
Independent Variables ◽  
High Degree ◽  
Sago Bark ◽  
Mixture Sample

The objective of this study was to assess the efficiency of a novel TiO2/modified sago bark (TiO2/MSB) mixture for the degradation of sago wastewater effluent by employing response surface methodology (RSM) using chemical oxygen demand (COD) removal as the target parameter. The highest COD removal of 64.92% was obtained using TiO2/MSB mixture sample prepared by combining 0.2 g/L TiO2and 1 w/w% MSB. Given that the highest removal was produced using this mixture sample, further optimisation of sago wastewater treatment was conducted by varying the independent variables, namely, dosage and contact time. Under this optimum condition, 0.10 g of 0.2 g/L TiO2/1% MSB had successfully reduced 52.83% COD in 120 min. Surface morphology, functional groups, and elemental analysis supported observations of the ability of TiO2/MSB mixture to remove COD. Additionally, aeration had further improved COD removal by 11%. The regression value (R2>0.99) of the model indicated a high degree of correlation between the evaluated parameters. These results proved the feasibility of TiO2photocatalysis as an appealing alternative protocol for sago wastewater treatment and solid waste from the industry can be utilised for wastewater degradation.

scholarly journals Evaluation of the effectiveness of anti-turbulent additives in the oil pipeline transportation

2020 ◽  
Vol 157 ◽  
pp. 02005
Author(s):  
Aleksei Balabukha ◽  
Valentina Zvereva
Keyword(s):  
Friction Coefficient ◽  
Experimental Studies ◽  
Computer Application ◽  
Eastern Siberia ◽  
Practical Application ◽  
Pipeline Transportation ◽  
Pressure Losses ◽  
Oil Pipeline ◽  
Oil Pipelines ◽  
High Degree

The authors of the article have developed the computer application allows to determine the value of the friction coefficient λ and anti-turbulent additives efficiency with a high degree of accuracy. The program can be used in the calculations and design of oil pipelines. The paper presents experimental studies of the effect anti-turbulent additives on the magnitude of pressure losses during fluid movement through pipes. The data gained by the developed computer program has been proved by the data of practical application of additives in the real oil pipeline transportation system called Eastern Siberia-Pacific Ocean oil pipeline.

Research on Heat and Mass Transfer of Flat Grooved Heat Pipes

2015 ◽  
Vol 733 ◽  
pp. 599-602
Author(s):  
Lei Cao ◽  
Guo Chang Zhao ◽  
Li Ping Song ◽  
Tian Dong Lu
Keyword(s):  
Heat Transfer ◽  
Mass Transfer ◽  
Temperature Control ◽  
Experimental Studies ◽  
Heat Pipes ◽  
Electronic Systems ◽  
Temperature Uniformity ◽  
Flat Surfaces ◽  
Flow And Heat Transfer ◽  
High Degree

Flat grooved heat pipes, which are especially useful in obtaining a high degree of temperature uniformity on flat surfaces, have been successfully used in the temperature control of electronic systems, however, the mechanisms governing the flow and heat transfer of this kind of heat pipes are still under scrutiny as some reported results cannot be reproduced by others or some assumptions have been proven to be unreasonable or ideal. The theoretical and experimental studies on flat grooved heat pipes and introduce work performed on modeling flat grooved heat pipes are reviewed in this paper.

Improving the stiffness of the aerostatic thrust bearing by using a restrictor with multi-orifice series

2020 ◽  
Vol 234 (12) ◽  
pp. 1881-1891
Author(s):  
Yueqing Zheng ◽  
Guangwei Yang ◽  
Hailong Cui ◽  
Yu Hou
Keyword(s):  
Thrust Bearing ◽  
Experimental Studies ◽  
Aerostatic Bearing ◽  
Small Aperture ◽  
In Series ◽  
New Construction ◽  
Bearing Stiffness

To improve the stiffness of the orifice-type aerostatic bearing, a new construction of orifice restrictor with multiple orifices in series was proposed to enhance the restriction effect. The restriction effects of the restrictors with multiple orifices in series were studied numerically. Based on a circular aerostatic thrust bearing with a central feedhole, the effect of the bearing stiffness improved by the restrictors with multiple orifices in series was studied. The results show that the aerostatic bearing with the restrictors with multiple sub-orifices in series shows higher maximal bearing stiffness than the bearing with traditional simple orifice restrictor. For example, the maximal stiffness for aerostatic bearing with the restrictor of four sub-orifices in series is 57 N/µm, which is ∼11% larger than that of the bearing with simple orifice. With this construction, the restriction effect of the orifice restrictor can be enhanced by increasing the number of the sub-orifices, instead of decreasing the aperture of the orifice. This approach avoids the difficulty of manufacturing the orifice restrictor with too small aperture for achieving a high restriction effect. The feasibility of the restrictor with multiple sub-orifices in series proposed in this paper was verified with experimental studies.

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