Rapid recycling of waste salt core materials in foundry industry using fractional crystallization

Xiaolong Gong,Xiongjie Xiao,Qianqian Li,Jianwei Zhao,Zitian Fan 한국공업화학회 2023 Journal of Industrial and Engineering Chemistry Vol.124 No.-

The water-soluble composite salt core materials have attracted increasing interest in the manufacture ofhollow castings with complex structures due to their high strength and excellent water solubility, whilethe treatment of waste brine generated from the salt core represents a major pain point for its large-scaleapplication. To change the above situation, the recycling technology of the waste brine from compositesalt core materials was developed using cooling crystallization combined with solvent-driven crystallization. The influences of dissolution temperature and solvent content on the recovery rate of the compositesalt core materials, including inorganic salt and fortifier, were investigated. In addition, the mechanicalproperties and microstructures of the composite salt core with multiple cycles were compared and analyzed. The results show that the fortifier material of corundum powder exhibits excellent chemical andthermal stability with a 100% recovery rate, and the recovery rate of inorganic salt material can reach79.31% with a 40 C dissolution temperature and a 1.0 mass ratio of methanol to brine. The microstructures,phase compositions and mechanical properties of the multi-recycled composite salt core have notchanged, demonstrating that the recycling of the water-soluble composite salt core is feasible, and favoringthe green development of the foundry industry.

One Step Fabrication of Micro-hole on SiCp/Al Cambered Surface by Micro-EDM and Mechanical-reaming Combined Machining

Sirui Gong,Han Wang,Xiaolong He,Zhenlong Wang,Yukui Wang 한국정밀공학회 2023 International Journal of Precision Engineering and Vol.10 No.4

SiCp/Al, as a new material, is widely used for its excellent wear resistance, corrosion resistance and other properties. Micro-holes are important but difficult to obtain on this ceramic material especially in curved surface. In this paper, taking micro bearing bush as an example, a micro-EDM and in-situ micro-reaming method is put forward for preparing micro through holes and micro eccentric holes on SiCp/Al cambered surface, without secondary clamping or tool change. High machining efficiency, low wear and no recasting layer can be achieved by this method. Here, machining characteristics is studied in hole micro-EDM on SiCp/Al, small taper and high efficiency machining is realized by comparing four electrical discharge drilling technique. Carbon deposition and tool wear are related to electrical parameters according to experimental exploration. After determining the discharge gap, taper and recast layer thickness, a segmented tool is designed, which can use the lower part to perform micro-EDM with the taper of 1.04°, MRR is 0.069 mm3/min, and the TWR is 3.22%. Then only needs to continue feeding the tool, the upper part of the tool can be used to achieve reaming, which can fully remove the recast layer, and decreases the roughness of hole wall from Ra 1.452 μm to Ra 0.803 μm.

Case Study on the Method of Rock Mass Overburden Consolidation Grouting for Dam Foundation

Jinxi Dou,Xiaolong Yang,Pan Gong,Zhilin Wang,Kexiang Wang,Tiangang Zhou,Weiquan Zhao 대한토목학회 2023 KSCE Journal of Civil Engineering Vol.27 No.10

Conventional grouting methods present challenges in achieving effective surface rock grouting and avoiding interference with concrete grouting and construction processes. The proposed approach includes reserving rock overburden, controlling grouting pressure and concentration, using a segmented grouting method, and selecting appropriate materials to develop a key method for consolidation grouting. This method not only overcomes the problems associated with the conventional consolidation grouting method but also effectively protects the thin layer of breccia lava in the Baihetan Dam foundation and solves the problem of unloading and relaxation of columnar jointed basalt caused by exposed consolidation grouting. The results show that the post grouting inspection hole permeability qualification rate is 99.3%, with the proportion of high-speed measuring points of various rock types ranging from 91.8% to 93.3%, and the proportion of low-speed measuring points ranging from 2.0% to 2.9%. The drop rate of the grout take of sequence I and sequence II is between 30% − 60%, except for some dam sections. These results indicate that the proposed method for consolidation grouting meets the design requirements. The findings have significant implications for the design and construction of consolidation grouting in similar projects.

Research on Machining Deformation of 7050 Aluminum Alloy Aircraft Rib Forging

Yaoqiong Liu,Hai Gong,Yongbiao He,Tao Zhang,Yanjie Sun,Xiaolong Liu 한국정밀공학회 2022 International Journal of Precision Engineering and Vol.23 No.5

T-type rib strip was the key connective component between the fuselage and wing of the aircraft and the main processes for preparation of T-type rib strip consisted of forging forming, solution quenching, cold pressing and machining. The variation of residual stress and its effect on the deformation during the final machining process was quite complex. In this study, the numerical models of solution quenching, cold pressing and machining of T-type rib strip was established. The variation of residual stress on the deformation of T-type rib strip was studied. The results show that the maximum quenching stress of the T-type rib was about − 200 MPa at the surface and 150 MPa in the core. A reduction of 60% of the average residual stress can be achieved during the cold pressing process with a reduction rate of 3% and a friction coefficient of 0.3. Compared with direct machining after quenching, the deformation of machining after solution quenching and cold pressing was greatly reduced and the reduction rate reached 65.04%.

Comparative transcriptome analysis of wing discs from Bombyx mori and Bombyx mandarina

Feng Yongjie,Kumar Dhiraj,Hu Xiaolong,Zhang Yiling,Zhu Min,Xue Renyu,Cao Guangli,Gong Chengliang 한국응용곤충학회 2020 Journal of Asia-Pacific Entomology Vol.23 No.2

The insect wing is developed from the wing imaginal disc which is designed from the embryonic ectoderm. To get insight into gene expression profiles in wing discs of Bombyx mori during metamorphosis, we compared the gene expression in the wing between B. mori and B. mandarina moth through RNA-seq. Out of total valid reads identified from the 5th day of 5th instar larvae of silkworm (L5), 7th day of pupae (P7), 1st day of moth (M1) and 1st day of wild silkworm moth (WM1), 20,092,004, 29,251,647, 24,654,695 and 19,753,089 reads were mapped to the mRNA reference sequences of silkworm, respectively. 9229, 7048, 9268 and 6701 differentially expressed genes (DEGs) were respectively recorded in P7 vs L5, M1 vs P7, M1 vs L5 and WM1 vs M1. Further, the peroxisome, ribosome, endocytosis and oxidative phosphorylation pathways were significantly regulated in the metamorphosis of the silkworm. Our study identified 16 orthologous genes with a positive selection from M1, which might be subjected to artificial selection in the domestication of B. mori and would play vital roles in the flight of B. mandarina.

Study of gut bacterial diversity of Bombyx mandarina and Bombyx mori through 16S rRNA gene sequencing

Dhiraj Kumar,Zhenli Sun,Guangli Cao,Renyu Xue,Xiaolong Hu,Chengliang Gong 한국응용곤충학회 2019 Journal of Asia-Pacific Entomology Vol.22 No.2

The wild silkworm B. mandarina is living in the natural environment has a strong stress resistance and adaptability after harsh natural selection. The indoor rearing or domestication of the wild silkworm under artificial custody for long period deteriorates stress resistance and ecological adaptability. Therefore, we aimed to investigate the effects of artificial domestication and evolutionary pressure on the gut bacterial diversity of B. mandarina and B. mori. The intestinal content of 6th day of fifth instar B. mandarina and B. mori larvae were analyzed by sequencing of the 16S rRNA gene through Illumina miseq sequencing technology. The outcome of the study revealed that abundance of predominant bacteria of phylum Firmicutes were respectively 81.40% and 81.85% in the late fifth instar silkworm larvae (6th day) of B. mandarina and B. mori. In Firmicutes, abundance of predominant bacterial genus Enterococcus in B. mandarina (69.73%) was comparatively higher than B. mori (48.99%). The genus Advenella belongs to phylum Proteobacteria was recorded only in B. mandarina (11.54%). The abundance of Unclassified_Peptostreptococcaceae, Methanobrevibacter, Ignatzschineria, Petrimonas and Proteiniphilum in B. mandarina were between 0.12 and 0.17%, nevertheless, these bacterial genera were not detected in B. mori. The abundance of genera Lactococcus, Bacillus and Pseudomonas in B. mori (17.73%, 5.02%, and 1.61%) were remarkably higher than B. mandarina (0.15%, 0.54% and 0.45%). These results indicated that substantial difference was observed between the intestinal bacteria of B. mori and B. mandarina population, and structure of the intestinal bacteria could be affected by the artificial domestication and evolutionary pressure.

Transient propagation of BmLV and dysregulation of gene expression in nontarget cells following BmLV infection

Feng Yongjie,Zhang Xing,Kumar Dhiraj,Kuang Sulan,Liu Bo,Hu Xiaolong,Zhu Min,Liang Zi,Cao Guangli,Xue Renyu,Gong Chengliang 한국응용곤충학회 2021 Journal of Asia-Pacific Entomology Vol.24 No.3

Bombyx mori latent virus (BmLV), a novel positive-strand RNA virus was first identified in the B. mori cultured BmN cell line. Whether the infectivity of BmLV to silkworm larvae and non-silkworm cells is connected with dysregulation of gene expression are not well understood. A complete sequence of BmLV genomic RNA was identified and revealed that a fragment with 495 nt in length was deleted from the RNA-dependent RNA poly merase (RdRp) gene in some BmLV genomic RNAs. Studies on the infectivity of BmLV to nontarget cells showed that BmLV can infect silkworm larvae, Spodoptera frugiperda Sf-9 and H1299 lung cancer cells with transient propagation. The dysregulation of gene expression of Sf-9 cells followed by BmLV infection was analyzed. Out of 743 differentially expressed genes (DEGs), 300 were upregulated and 443 were downregulated. Gene Ontology (GO) analysis indicated the DEGs were enriched into oxidoreductase activity for CH-NH 2 group donors, gluta mate biosynthetic process, response to stress and proteasome core complex. KEGG enrichment analysis showed that DEGs were mainly enriched into sulfur metabolism, RNA degradation, proteasome, pentose and glucuronate interconversions. Undesirable nutrients and temperature factors contributed to the propagation of BmLV in Sf-9 cells. Additionally, the Imd and RNAi pathways were activated by BmLV infection without stimulating Toll and JAK-STAT pathways. Therefore, it is suggested that BmLV is originated from plants, which can enter nontarget cells with transient propagation. The transient infection of BmLV may not only be regulated by Imd and RNAi immune pathways but also mediated by dysregulation of gene expression.

Cell proliferation can be modulated by receptor tyrosine kinase-like orphan receptor 2 in the silkworm, Bombyx mori

Yongjie Feng,Wei Liu,Dhiraj Kumar,Min Zhu,Renyu Xue,Guangli Cao,Xiaolong Hu,Chengliang Gong 한국응용곤충학회 2023 Journal of Asia-Pacific Entomology Vol.26 No.4

The receptor tyrosine kinase-like orphan receptor 2 (Ror2) is involved in the Wnt/β-catenin signaling pathway which regulates cell proliferation, polarity, differentiation, migration, metabolism and survival. However, the function of Ror2 in the silkworm Bombyx mori is still undisclosed. In the present investigation, we have made an effort to clone the silkworm Ror2 gene (BmRor2). The sequence analysis showed that the open reading frame (ORF) was 1914 bp in size and encoded a protein with the conserved domains of Ror2 protein. The qRT-PCR results indicated that the BmRor2 gene expression level was the highest in the head among all identified tis sues on 3rd day of the fifth instar larvae. In the gonads of the different development stages, the BmRor2 gene expression level was highest on the 4th day of the fourth instar larvae. The immunofluorescence assay indicated that the BmRor2 protein was located at the cytomembrane. The effects of BmRor2 protein on the expression levels of genes related to TGF-β, Hippo, JAK-STAT and Notch signaling pathways were investigated by qRT-PCR. The expression levels of crumbs (crb), warts (wts), α-catenin (cat), four-jointed (fj), decapentaplegic (dpp), kibra ortholog (kibra), serrate (serr) and c-myc (myc) genes were down-regulated, whereas, suppressor of cytokine signaling 2 (socs 2) gene expression was up-regulated in the cultured BmN cells after the BmRor2 expression level was up-regulated. Further, cell proliferation was demoted and the size of cells was decreased when BmRor2 expression level was elevated. Our current finding recommended that BmRo2 can regulate TGF- β, Hippo, JAKSTAT, and Notch signaling pathways, and affect cell proliferation and size.

Metatranscriptomic sequencing reveals there were abundant and diverse viruses in the midgut of diseased silkworm (Bombyx mori) with soft rot symptoms

Qiu Qunnan,Pan Jun,Kumar Dhiraj,Wei Shulin,Tong Xinyu,Zhu Min,Hu Xiaolong,Gong Chengliang 한국응용곤충학회 2023 Journal of Asia-Pacific Entomology Vol.26 No.4

To date, six viruses belonging to genera Alphabaculovirus, Cypovirus, Iflavirus, Iteravirus, Bidensovirus and Maculavirus were harbored in the silkworm (Bombyx mori) and in the cultured BmN cells. Diseased silkworms with unknown etiology often create economic losses to the farmers. In the present investigation, the abundance and diversity of viruses in the midgut of diseased silkworms with soft rot symptoms were assessed by meta transcriptomic sequencing in order to screen the potential pathogenic virus of the silkworm, B. mori. After removal of undefined reads, clean reads were assembled, and the obtained 76 viral unigenes were annotated to 43 viruses. Among these viruses, the B. mori cypovirus, Pieris rapae virus, Nodaviridae sp., B. mori bidensovirus, Pseudomonas virus pf16, Pseudomonas phage Skulduggery, Klebsiella phage KPN U2874, Equid gamma herpesvirus 2, fowlpox virus and Xestia c-nigrum granulovirus were dominant virus species. These metatran scriptomic sequencing results provided new clues for screening and identifying novel pathogenic virus of the silkworm.

A Study on BMPR-IB Genes of Bayanbulak Sheep

Zuo, Beiyao,Qian, Hongguang,Wang, Ziyu,Wang, Xu,Nisa, Noor,Bayier, Aierdin,Ying, Shijia,Hu, Xiaolong,Gong, Changhai,Guo, Zhiqin,Wang, Feng Asian Australasian Association of Animal Productio 2013 Animal Bioscience Vol.26 No.1

The average twin lambing rate of Bayanbulak sheep is 2% to 3%. However, a flock of sheep with a close genetic relationship and an average of 2 to 3 lambs per birth has been found recently. To determine the major genes controlling the prolificacy of the flock in the present study, the flock was designated A while 100 normal Bayanbulak sheep were randomly selected to comprise the control flock B. Ligase detection reaction method was applied to detect and analyze the 10 mutational loci of the 3 candidate prolificacy genes including bone morphogenetic protein type I receptors, bone morphogenetic protein 15, and growth differentiation factor 9. The 10 mutational loci are as follows: FecB locus of the BMPR-IB gene; $FecX^I$, $FecX^B$, $FecX^L$, $FecX^H$, $FecX^G$, and $FecX^R$ of the BMP15 gene; and G1, G8, and FecTT of the GDF9 gene. Two mutations including BMPR-IB/FecB and GDF9/G1 were found in Bayanbulak sheep. Independence test results of the two flocks demonstrate that the FecB locus has a significant effect on the lambing number of Bayanbulak sheep. However, the mutation frequency of the G1 locus in GDF9 is very low. Independence test results demonstrate that the GDF9 locus does not have a significant impact on the lambing performance of Bayanbulak sheep. Among the 10 detected loci, BMPR-IB/FecB is the major gene that influences the high lambing rate of Bayanbulak sheep.