Study of Micro-Inclusion of 20g Steel

According to the production process of 20g steel(120t BOF→ LF→ CC), some system analysis are introduced to research on the content of T[O] and [N] and the type, source, composition and quantity of micro inclusions in refining process, pouring process and casting billet. The results of the study show: the content of T[O] is 93.2ppm in the normal billet which is 37.8ppm more than that at steady state in the export of tundish. The content of T[O] is 140.5ppm in the compound casting billet which is 70.133ppm more than that at non-steady state in the export of tundish. The secondary oxidation of mould is serious at casting progress. In billet, the quality of CaS-SiO2-Al2O3 complex inclusion is the most, the quality of MnS inclusion is the second, and the quality of Al2O3 inclusion is the least. The sulphur content in micro-inclusion of billet is higher. The sulphur content in CaS-SiO2-Al2O3 complex inclusion is 3~15%, the sulphur content in MnS inclusion is 25%. The particle size of less than 10μm in micro-inclusions is the largest. The particle size of 0~5μm is about 60%, the particle size of 5~10μm is about 35%, the particle size of 10~15μm is about 5%. The average total volume rate of micro-inclusion is 0.149% in normal billet. The average total volume rate of micro-inclusion is 0.184% in compound casting billet which is 1.23 times than normal billet. The number of micro-inclusion is 36.5/ mm2 in normal billet. The number of micro-inclusion is 58.5/ mm2 in compound casting billet which is 60.27% higher than normal billet. The non-steady state casting has serious influence on billet cleanliness.

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Study of Micro-Inclusion of Grade 45 Steel

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.634-638.1869 ◽

2013 ◽

Vol 634-638 ◽

pp. 1869-1873

Author(s):

Bu Qing Xiao ◽

Sheng Fu Li ◽

Xiao Tao Tian ◽

Jian Xing Wang

Keyword(s):

Particle Size ◽

Production Process ◽

System Analysis ◽

Volume Ratio ◽

Slag Refining ◽

Type Composition ◽

Compound Casting ◽

Al2o3 Inclusion

According to the production process of grade 45 steel(120tBOF→slag refining→ CC), some system analysis are introduced to research on the type composition and quantity of micro-inclusions, and the effect of slag washing production process on the cleanliness of casting slab is evaluated. The results of the study show that: The content of T[O] is 48.75ppm in normal slab, The content of T[O] is 56.2ppm in head slab, The content of T[O] is 49.2ppm in compound casting slab.The main types of micro-inclusion in slab are MnS inclusion and Al2O3 inclusion. The quality of micro-inclusions is 14.32/mm2 in the normal slab, the quality of micro-inclusions is 17.68 /mm2 in the head slab, the quality of micro-inclusions is 27.94 /mm2 in the compound casting. In the normal slab, the average total volume ratio of micro-inclusions is 0.0458%. The particle size of micro-inclusions is smaller. The particle size of less than 10μm in micro-inclusions is the largest and is about 80%.

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Study on the Large Inclusions in 20g Steel

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.634-638.1874 ◽

2013 ◽

Vol 634-638 ◽

pp. 1874-1878

Author(s):

Li Guang Zhu ◽

Ruo Si Wang ◽

Cheng Liang Du

Keyword(s):

Particle Size ◽

Production Process ◽

System Analysis ◽

Main Type ◽

Refining Process ◽

Complex Inclusion ◽

Compound Casting ◽

Steel Cleanliness

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Study of Large Inclusions in Casting Slab of 45# Steel

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.634-638.1859 ◽

2013 ◽

Vol 634-638 ◽

pp. 1859-1863

Author(s):

Ju Gao ◽

Cheng Liang Du

Keyword(s):

Production Process ◽

System Analysis ◽

Slag Refining ◽

Spherical Inclusions ◽

Type Composition ◽

Washing Process ◽

Compound Casting ◽

Bof Slag ◽

Al2o3 Inclusion ◽

Slag Entrapment

According to the production process of 45#steel(120t BOF→ slag refining →CC), some system analysis are introduced to research on the type, composition and quantity of large inclusions in casting slab under slag washing process, the effect of slag washing production process on the cleanliness of casting slab is evaluated. The results of the study show that: Under slag washing process, many of large inclusions are spherical inclusions，the main type of large inclusions is CaO-SiO2-Al2O3-MnO complex inclusion andSiO2-Al2O3 inclusion; the content of large inclusions in normal slab is 5.17mg/10kg, it is lower than that under un-slag washing process; the content of large inclusions in head slab is 108.82mg/10kg, it’s 21.05 times higher than that in normal slab; the content of large inclusions in compound casting slab is 15.94mg/10kg, it’s 3.08 times higher than that in normal slab; the content of large inclusions in casting slab is slightly higher under the condition of unsteady casting; the main inclusions with a size of between 140μm and 300μm in head slab, take up 70.13%, the inclusions with a size of more than 300μm is second, take up 29.24%, and the least is inclusions with a size of between 80μm and 140μm, only take up 0.63%. The level of the molten steel fluctuated remarkably, slag entrapment and secondary oxidation is serious at the casting start and compound casting, which cause the cleanliness of casting slab decreasing. Unsteady casting has great effect on the cleanliness of casting slab.

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Modification of tundish design to improve quality of slabs, casted at CCM No. 4 of EVRAZ NTMK

Ferrous Metallurgy Bulletin of Scientific Technical and Economic Information ◽

10.32339/0135-5910-2020-6-559-563 ◽

2020 ◽

Vol 76 (6) ◽

pp. 559-563

Author(s):

I. M. Zakharov ◽

V. A. Smirnov ◽

D. V. Sushnikov ◽

A. G. Lyzhin ◽

E. A. Lavrova ◽

...

Keyword(s):

Basic Number ◽

Metal Level ◽

Surface Layers ◽

Secondary Oxidation ◽

Strip Rolling ◽

Actual Distribution ◽

Ultrasonic Control ◽

Analysis Of Results ◽

Water Simulation

A technology of continuous casting of steel has a large effect on its contamination. In particular, proper organization of metal flows in tundish and mold is very important. After completion a series of casting through a tundish and drop of metal level in it, it possible, that the slag flows from the surface layers of the tundish to capture the metal. An analysis of results of ultrasonic control of finished strip showed, that the basic number of the revealed defects was obtained during strip rolling out of the last slabs of the last heat in a series for a tundish. Metallographic studies determined, that the defects were located in the slab axis zone and filled by macro-inclusions of complex composition. To determine the actual distribution of metal flows, a water simulation of them was accomplished for the existing design of the EVRAZ NTMK tundish. It was determined, that at the drop of metal level in a tundish, a capture of slag from the metal reservoir and its transfer into the main bath of the tundish takes place due to whirligig flows. Following the weight metal consumption, the zone of slag inclusions distribution enlarges. Besides, denudation of the metal mirror in the metal reservoir takes place, resulted in metal secondary oxidation. Based on the results of the simulation, it was proposed to modify the design of the “turbostop”, which is installed in the metal reservoir of the tundish. Besides, it was proposed to remove the dividers installation in the tundish. It was noted, that the proposed steps enable to ensure a minimal level of rejections.

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Managing the effectiveness of the regional health system

Finance and Credit ◽

10.24891/fc.26.3.698 ◽

2020 ◽

Vol 26 (3) ◽

pp. 698-720

Author(s):

E.V. Lobkova ◽

A.S. Petrichenko

Keyword(s):

Public Health ◽

Health System ◽

System Analysis ◽

Health Indicators ◽

Krasnoyarsk Krai ◽

Regional Health ◽

Luenberger Observer ◽

Efficiency Assessment ◽

Public Health Indicators

Subject. This article studies the mechanism of State health regulation and methods of management of efficiency of regional healthcare institutions. Objectives. The article aims to analyze the territorial health system in the context of the urgent need to optimize budget expenditures and address public health problems, as well as develop directions to improve the effectiveness of the regional health system of the Krasnoyarsk Krai. Methods. For the study, we used the method of index numbers and calculation of dynamics indicators using official statistics data. Results. We have developed and now present a system of indicators of regional health efficiency assessment, focused mainly on public health indicators and quality of medical services. We also offer our own version of the Luenberger observer modification adapted to the objectives of the regional health system analysis. Conclusions and Relevance. The article concludes that it is necessary to optimize the regional health system using the parameters of medical and social efficiency of the system. The proposed approach to assessing the effectiveness of regional health system can be used as a mechanism to develop recommendations for the management of the network of medical and prophylactic institutions of the region.

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The Influence of Extruded Sugar Beet Pulp on Cookies' Nutritional, Physical and Sensory Characteristics

Sustainability ◽

10.3390/su13095317 ◽

2021 ◽

Vol 13 (9) ◽

pp. 5317

Author(s):

Sonja Simić ◽

Jovana Petrović ◽

Dušan Rakić ◽

Biljana Pajin ◽

Ivana Lončarević ◽

...

Keyword(s):

Particle Size ◽

Sugar Beet ◽

Dietary Fiber ◽

Wheat Flour ◽

Nutritional Quality ◽

Sugar Beet Pulp ◽

Sensory Characteristics ◽

Total Dietary Fiber ◽

Beet Pulp

Sugar beet pulp (SBP) is a by-product of the sugar industry in which the dietary fiber content ranges from 73% to 80%. Compared to cereal fibers mainly used in biscuit production, sugar beet fibers are gluten free and have a perfect ratio of 2/3 insoluble fiber. In this work, sugar beet pulp was extruded with corn grits (ratios of corn grits to sugar beet pulp in extrudates were 85:15, 70:30, and 55:45), and the obtained sugar beet pulp extrudates (SBPEs) were used for improving the nutritional quality of cookies. The wheat flour in cookies was replaced with SBPEs in the amount of 5, 10, and 15%. The influence of three factors (the percentage of sugar beet pulp in the SBPEs, the size of the SBPE particles, and the percentage of wheat flour substituted with SBPEs) and their interactions on the nutritional quality of cookies, as well as their physical and sensory characteristics are examined using the Box–Behnken experimental design. The addition of extruded sugar beet pulp (SBPEs) significantly increased the amount of total dietary fiber and mineral matter of cookies. On the whole, the addition of SBPEs increased cookie hardness, but the hardness decreased with an increase in extrudate particle size. Sensory characteristics (except for the taste) were the most influenced by extrudate particle size.

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A Head Formulation for the Steady-State Analysis of Water Distribution Systems Using an Explicit and Exact Expression of the Colebrook–White Equation

Water ◽

10.3390/w13091163 ◽

2021 ◽

Vol 13 (9) ◽

pp. 1163

Author(s):

Mengning Qiu ◽

Avi Ostfeld

Keyword(s):

Steady State ◽

Distribution System ◽

Distribution Systems ◽

Water Distribution ◽

Solution Method ◽

Water Distribution System ◽

Academic Research ◽

Exact Expression ◽

Contamination Source

Steady-state demand-driven water distribution system (WDS) solution is the bedrock for much research conducted in the field related to WDSs. WDSs are modeled using the Darcy–Weisbach equation with the Swamee–Jain equation. However, the Swamee–Jain equation approximates the Colebrook–White equation, errors of which are within 1% for ϵ/D∈[10−6,10−2] and Re∈[5000,108]. A formulation is presented for the solution of WDSs using the Colebrook–White equation. The correctness and efficacy of the head formulation have been demonstrated by applying it to six WDSs with the number of pipes ranges from 454 to 157,044 and the number of nodes ranges from 443 to 150,630. The addition of a physically and fundamentally more accurate WDS solution method can improve the quality of the results achieved in both academic research and industrial application, such as contamination source identification, water hammer analysis, WDS network calibration, sensor placement, and least-cost design and operation of WDSs.

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Effects of Flour Particle Size and Starch Damage on Processing and Quality of White Salted Noodles

Cereal Chemistry ◽

10.1094/cchem.2002.79.1.64 ◽

2002 ◽

Vol 79 (1) ◽

pp. 64-71 ◽

Cited By ~ 67

Author(s):

D. W. Hatcher ◽

M. J. Anderson ◽

R. G. Desjardins ◽

N. M. Edwards ◽

J. E. Dexter

Keyword(s):

Particle Size

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Performance, carcass traits and meat quality of lambs fed with different roughage:concentrate ratios associated with variable physically effective neutral detergent fibre content

The Journal of Agricultural Science ◽

10.1017/s0021859621000459 ◽

2021 ◽

pp. 1-11

Author(s):

L. de O. Queiroz ◽

A. M. Barbosa ◽

G. B. Mourão ◽

M. A. Fonseca ◽

L. F. B. Pinto ◽

...

Keyword(s):

Fatty Acids ◽

Particle Size ◽

Meat Quality ◽

Average Daily Gain ◽

Carcass Traits ◽

Faecal Excretion ◽

Neutral Detergent Fibre ◽

Fatty Acids Profile ◽

Colour Parameter

Abstract This study evaluated the effect of roughage:concentrate (R:C) ratio associated with a variable particle size of physically effective neutral detergent fibre (peNDF8) in the forage (Tifton-85 hay) on the performance, carcass traits and meat quality of lambs. Seventy-two 4-month-old, non-castrated Santa Ines male lambs (23.5 ± 2.32 kg BW) were distributed in a completely randomized design, in a 2 × 2 factorial arrangement [two peNDF8 hay particle sizes (13 and 6 mm) and two R:C ratios (700:300 and 500:500 g/kg DM total)]. DMI, DM, NFC and TDN digestibility's, N-intake and N-faecal excretion were affected by the R:C ratio (P < 0.05). However, the N-retained was not affected by the studied variables (P > 0.05). It was observed an interaction (P < 0.05) between the peNDF8 and R:C ratios for final BW, average daily gain (ADG), colour parameters and pH 24 h. The lower roughage ratio provided greater (P < 0.05) concentrations of C14:1, C16:1–cis9, C18:1–cis9, ΣMUFA, Σn–6:Σn–3 and hypocholesterolemic/hypercholesterolemic index, enzymatic activity Δ9desaturase-C16 and -C18. Lambs fed a lower roughage diet had improved performance and feed efficiency, however, presented reduced polyunsaturated fatty acids (PUFA) concentrations in the meat, especially Σn–3 family. Higher roughage diet and larger peNDF8 particle size improved the concentrations of PUFA while decreased Σn–6:Σn–3 ratio in meat. Larger peNDF8 particle size associated with higher roughage proportion, have reduced animal performance however, it increased protein concentration, a* and C* colour parameter without affecting fatty acids profile of Longissimus lumborum muscle.

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Difficulty in Assessing Quality of Life Outcomes in a Fluctuating Disease: A Hypothesis Based on Gastroparesis

Gastroenterology Research and Practice ◽

10.1155/2009/396190 ◽

2009 ◽

Vol 2009 ◽

pp. 1-3 ◽

Cited By ~ 2

Author(s):

Vic Velanovich

Keyword(s):

Quality Of Life ◽

Steady State ◽

Disease Process ◽

Preliminary Finding ◽

Median Number ◽

Underlying Assumption ◽

Clinical Encounters ◽

Idiopathic Gastroparesis ◽

Clinic Visits

An underlying assumption of quality of life outcome research is that after some intervention a “steady-state” of quality of life is reached which can be identified as an endpoint, and, hence, the “outcome.” However, in some disease processes, no so such steady-state is reached. The hypothesis presented is that a disease process with a waxing and waning course will make it difficult to determine a quality of life endpoint. After clinical observation, a pilot study of patients with either diabetic or idiopathic gastroparesis with gastric neurostimulation their records were reviewed to identify the number of clinic visits, the number of clinic visits in which the patients were asymptomatic, much improved, improved, no change, worse, or much worse. These changes were defined as “transitions.” A “transition ratio” was calculated by dividing the number of transitions by the number of clinic visits. Preliminary results showed that of 32 patients, the median number of clinic encounters was 8 (1–35), and the median number of transitions 4 (0–22). The average transition ration was . In the case of gastroparesis, over half of all clinical encounters were associated with a transition. The implication of the hypothesis and preliminary finding suggests a difficulty to identify when the symptomatic endpoint was reached. Other methods to assess the effects of treatment in such a disease process are required to fully understand the effects of treatment on quality of life.

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