Letteratura scientifica selezionata sul tema "A.W. Lindsay Type Foundry"

Research has been carried out on the synergism of a mixture of andisol soil and foundry sand as Cu(II) ion adsorbent. This study aims to determine the effect of mixing andisol soil and foundry sand on the absorption of Cu (II) ions and to study the type of isotherm and its adsorption kinetics model. The adsorbent was activated with 3 M NaOH. The acidity of the adsorbent was analyzed using the specific total acidity test method. The final concentration of Cu (II) ions was analyzed using AAS (Atomic Absorption Spectroscopy). The optimum adsorption conditions were obtained based on variations in composition, pH, and contact time. The adsorbent was made with variations in the composition of andisol: foundry sand 100:0, 75:25, 50:50, 25:75 and 0:100 (w/w). The effect of adsorption conditions was carried out by varying the pH of the copper (Cu) solution from 3-7. The effect of contact time was varied at 15-135 minutes with 15 Minute intervals.

In this paper, to substitute the existing TWTA(Travailing Wave Tube Amplifier) component in small radar system, we developed the Ku band SSPA(Solid-State Power Amplifier) based on the fabrication of power MMIC (Monolithic Microwave Integrated Circuit) chips. For the development of the 500 W SSPA, the 40 W-grade power MMIC was designed by ADS(Advanced Design System) at Keysight company with UMS GH015 library, and was processed by UMS foundry service. And 70 W main power modules were achieved the 2-way T-junction combiner method by using the 40 W-grade power MMICs. Finally, the 500 W SSPA was fabricated by the wave guide type power divider between the drive power amplifier and power modules, and power combiner with same type between power modules and output port. The electrical properties of this SSPA had 504 W output power, -58.11 dBc spurious, 1.74 °/us phase variation, and -143 dBm/Hz noise level.

In the foundry industry, silica sands are the most commonly used type of sands for the production of sand foundry moulds using various types of binders. Their greatest disadvantage is their significant volume changes at elevated temperatures, which are associated with the formation of many foundry defects from stress, such as veining, and thus have a direct influence on the final quality of the casting. In the case of non-silica sands and synthetic sands, the volume stability is more pronounced, but this is accompanied by a higher purchase price. Therefore, a combination of silica sand and synthetic sand CERABEADS is considered in order to influence and reduce the thermal expansion. The hybrid mixtures of sands, and their most suitable ratios, were evaluated in detail using sieve analysis, log W and cumulative curve of granularity. It was found that the addition of 50% CERABEADS achieves a 32.2% reduction in dilatation but may increase the risk of higher stresses. The measurements showed a significant effect of the granulometric composition of the sand on the resulting thermal expansion, where the choice of grain size and sorting can achieve a significant reduction in dilatation with a small addition of CERABEADS.

The work is devoted to the topical problem of increasing the efficiency of cleaning process of gases in packed-type scrubbers in order to reduce emissions of harmful substances and solid impurities into the atmosphere and improve the technical and economic indicators of wet gas cleaning systems. For this, a triangular cross-cut packing has been developed. Due to the size of the holes and their specific shape, the triangular packing provides longer contact of the packaging with water, which reduces water consumption. The packing is made of alloy steel AISI 316, so it can be used even in the most aggressive environment. In the work, the efficiency of cleaning with a scrubber with this packing is experimentally determined. The tests were performed at an ambient temperature of 23 °C. Several measurements were made for each type of packing, in a typical scrubber design. To conduct these industrial tests, a thermohygrometer-carbon dioxide gas analyzerAZ-7797 was used with high-precision NDIR (infrared) sensor, automatic background calibration (W/ABC), and compensation for deviations during long-term operation. The concentration measurement range is 0-9999 ppm with an error of ± 5 %. The gases were cooled in two stages. At first, they were cooled with ammonia water from 750 to 80 °C. Then they were fed to a primary gas refrigerator (basic type) of direct action, where its temperature were falled to 15 °C. Carbon dioxide concentration was measured after the first stage of cooling, after the final cooling, and after the cleaning process. The comparison is carried out with the most effective types of packing for wet gas cleaning today – chordal wood and Raschig rings. It is shown that the developed triangular packing with cross-shaped notches during the purification of coke oven gas from carbon dioxide improves the purification by 25 % in comparison with the wooden chord one, and by 15 % - with Raschig rings. This allows us to recommend it for widespread implementation.

The reuse of waste in construction has been an alternative to minimize the environmental impact and transform waste into raw material. The present study evaluated the replacement of natural sand by fine green foundry sand waste in the manufacture of foam concrete. Different levels of substitution were tested, as well as the amount of foam and the type of curing. The results indicated that the compressive strength ranged from 4.0 to 12.6 MPa, with mixtures with 20% foam and 50% fine green foundry sand waste (FGFSW) presenting results close to 6 MPa. The cementitious matrices presented uniform and distributed pores for mixtures with 20% foam in all levels of FGFSW substitution. The dry and saturated densities varied from 946 to 1743 kg/m³ and from 1244 to 1881 kg/m³, respectively. Thermal conductivity results ranged from 0.28 to 0.53 W/m.K and water absorption ranged from 4.5% to 38.2%. In summary, the study showed that it is possible to use the FGFSW for the manufacture of foamed cellular concrete with technical effectiveness.

Abstract More and more foundry plants applying moulding sands with water-glass or its substitutes for obtaining the high-quality casting surface at the smallest costs, consider the possibility of implementing two-layer moulds, in which e.g. the facing sand is a sand with an organic binder (no-bake type) and the backing sand is a sand with inorganic binder. Both kinds of sands must have the same chemical reaction. The most often applied system is the moulding sand on the water-glass or geopolymer bases - as the backing sand and the moulding sand from the group of self-hardening sands with a resol resin - as the facing sand. Investigations were performed for the system: moulding sand with inorganic GEOPOL binder or moulding sand with water glass (as a backing sand) and moulding sand, no-bake type, with a resol resin originated from various producers: Rezolit AM, Estrofen, Avenol NB 700 (as a facing sand). The LUZ apparatus, produced by Multiserw Morek, was adapted for investigations. A special partition with cuts was mounted in the attachment for making test specimens for measuring the tensile strength. This partition allowed a simultaneous compaction of two kinds of moulding sands. After 24 hours of hardening the highest values were obtained for the system: Geopol binder - Avenol resin.

The paper investigates the possibility of preventing the occurrence of closed-type shrinkage shells in the lower necks of СПХН-60 iron rolling rolls by changing the thermophysical and dimensional parameters of the elements of the combined foundry mold, which is currently used in foundries. The research was carried out based on the results of thermography of real rolls of СПХН-60, adaptation of the obtained data and computer modeling of the process of hardening of cast iron rolls in the combined casting-sand mold, as well as the first developed parametric criterion of sequential hardening in the system of the lower neck of the roll and its barrel. The regularities of the complex influence of the diameters of the barrel and the lower necks of the rolls, the sizes and thermophysical parameters of the materials of the combined form on the sequence of solidification of these casting elements have been established. The obtained data indicate that increasing the level of thermophysical properties of the molding mixture for the lower neck of the roll within the limits of the use of currently known refractory non-metallic materials does not prevent the occurrence of a shrinkage shell in the lower neck of the rolls of СПХН-60 execution. Increasing the level of the heat-accumulating capacity of the forming mixture for the lower neck of the roll to 10000 Ws 0,5 /(m²С) will prevent the occurrence of a shrinkage shell in the lower neck of the rolls of СПХН-60 performance, but it is not expedient due to the appearance of a layer of bleached iron in the lower neck, which is unacceptable for any rolling mill. To solve this problem, it is recommended for СПХН-60 rolls to use shielding of the roll combined form at a certain moment of solidification of the melt in the barrel. Рurposeof the work is to investigate the possibility of preventing the occurrence of closed-type shrinkage shells in the lower necks of rolling rolls due to changes in the thermophysical parameters of their forming mixtures. Methodology.The work uses the method of thermography and computer modeling using the LVMFlow program. Originality.For the first time, the regularities of the complex influence of thermophysical and dimensional parameters of the elements of the combined foundry mold on the occurrence of a shrinkage shell in the lower neck of the СПХН-60 rolling rolls were established.

The aim of this study was to evaluate the in situ bioprecipitation (ISBP) and zero-valent iron (ZVI) for removal of arsenic from groundwater. Batch experiments were set up to test the metal/oxyanion removal efficiency using the processes induced by ZVI, by ISBP and by combining both technologies. For the construction of microcosms in anaerobic condition, aquifer material was mixed with synthetic groundwater in serum bottles. Solutions that contained commercial iron (powder, filings), iron from foundry (chips) and lactate with the carbon concentration of 0.02% (w/v) were amended. After 57 days the pH increased to 7.9 in the microcosm with lactate + iron chips. In the microcosms amended with lactate + commercial iron (powder and filings), pH was between 6.9 and 7.5 The highest decrease in sulfate concentrations was observed in the microcosm supplied with lactate (from 1,976 to 630 mg/L), and with lactate + iron filings (from 1,985 to 1,280 mg/L). The results showed that ISBP and ZVI can be efficient in the removal of As from groundwater; however, it strongly depends on the type and particle size of ZVI. The most effective was commercial ZVI. The highest decrease in As concentration was observed in the microcosm supplied with ethanol and iron powder (from 4,832 to 131 μg/L).

A monomoprhic monoclonal antibody (LA45 antibody) reactive with "a new activation-induced surface structure on human T lymphocytes" (LA45 antigen) that resembled free class I heavy chains has recently been described (Schnabl, E., H. Stockinger, O. Majdic, H. Gaugitsch, I.J.D. Lindley, D. Maurer, A. Hajek-Rosenmayr, and W. Knapp. 1990. J. Exp. Med. 171:1431). This antibody was used to clone a class I-like heavy chain (LA45 gene) from the HUT 102 tumor cell, which paradoxically did not give rise to the LA45 antigen on transfection into monkey COS cells. We show here that the LA45 gene is HLA-Aw66.2, a previously uncharacterized allele of the HLA-A locus. The previously determined LA45 sequence differs from that of HLA-Aw66.2, from HUT 102, and the CR-B B cell line derived from the same individual as HUT 102 by substitution of tryptophan for serine at position 4 in the alpha 1 domain. Transfection of HLA-Aw66.2, and of a mutant of this gene with serine 4 substituted for tryptophan, into a human B cell line (C1R) both resulted in expression of the LA45 epitope. Furthermore, we find expression of the LA45 epitope on Epstein Barr virus-transformed B cell lines as well as lectin-activated T cells, but not on long-term T cell lines or unstimulated peripheral blood T cells. The specificity of the LA45 antibody is polymorphic and the presence of the LA45 epitope is precisely correlated with the sequence arginine, asparagine (RN) at residues 62 and 63 of the helix of the alpha 1 domain. The LA45 epitope is broadly distributed, being associated with half the alleles of both HLA-A and -B loci but none of the HLA-C locus. All the results are consistent with the presence of pools of free HLA-A and -B heavy chains at the surfaces of certain cell types but not others. Such molecules are probably responsible for the HLA-associated class I alloantigens of lectin-activated T cells. We hypothesize the free heavy chains result from dissociation of beta 2-microglobulin from subpopulations of empty HLA-A,B molecules, or molecules with weakly bound peptides, that vary in size depending on cellular activation and peptide supply.

Abstract Background: Increasing evidence suggests germline genetic susceptibility influences the risk of developing subsequent neoplasms (SNs)—a major cause of morbidity and mortality—among childhood cancer survivors, but studies have been hampered by sample size and limited gene sets. We pooled two large-scale cohorts of childhood cancer survivors to characterize overall and specific SN risks among individuals carrying germline variants in 88 known cancer susceptibility genes with an autosomal dominant inheritance pattern. Methods: Using whole-genome or whole-exome sequencing data from the Childhood Cancer Survivor Study and St. Jude Lifetime Cohort (median [interquartile range] follow-up, 29.7 [13.8] years), we identified rare, potentially protein-damaging germline variants with SnpEff/ClinVar. Conditional logistic regression evaluated overall SN and SN-specific risk, with up to 100 SN-free controls matched to cases by age, sex, primary childhood cancer type, SN type, radiation dose, chemotherapy, study, and follow-up time. Results: Among 11840 individuals (50.6% female) who survived childhood cancer, 2162 (18.3%) developed at least one SN. The risk of developing any SN was elevated among 288 survivors carrying rare, potentially protein-damaging germline variants in an autosomal dominant cancer susceptibility gene (cases=13.3%; controls=9.6%; odds ratio [OR], 1.48; 95% confidence interval [CI], 1.30-1.70; P=5.12x10-5). A similar proportion of carriers was observed among those who developed common SNs such as basal cell carcinoma (N=107/882, 12.1%), meningioma (N=52/373, 13.9%), breast cancer (N=49/353, 13.9%), and thyroid cancer (N=32/243, 13.2%). Higher frequencies of carriers were observed in less common SNs, specifically sarcoma (N=24/151, 15.9%), colorectal cancer (N=15/72, 20.8%), and glioma (N=16/64, 25.0%). The observed associations were generally consistent regardless of treatment type for first primary childhood cancer. Gene-specific analyses revealed that the risk of developing any SN was most pronounced among individuals carrying variants in TP53 (cases=0.6%; controls=0.04%; OR, 9.93; 95% CI, 4.62-21.34; P=0.001) and FANCM (cases=0.9%; controls=0.5%; OR, 2.45; 95% CI, 1.48-4.03; P=0.018). Conclusion: In large-scale cohorts of childhood cancer survivors with long-term follow-up, individuals carrying potentially protein-damaging germline variants in known autosomal dominant cancer susceptibility genes have substantially increased SN risk, emphasizing the importance of genetic testing and consideration of genetic risk in follow-up guidelines. However, these individuals account for a small fraction of all SN cases, warranting future research on underlying risk factors in this population. Citation Format: Shahriar A. Zamani, Danielle M. Karyadi, Stephen W. Hartley, Joshua N. Sampson, Todd Gibson, Peter Kraft, Stephen J. Chanock, Lindsay M. Morton. Germline variants in cancer susceptibility genes and subsequent neoplasm risks after childhood cancer: A pooled analysis of two large-scale cohorts [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 6155.