Microstructure Refi nement and Strengthening Mechanisms of a 9Cr Oxide Dispersion Strengthened Steel by Zirconium Addition

Haijian Xu,Zheng Lu,Dongmei Wang,Chun Ming Liu 한국원자력학회 2017 Nuclear Engineering and Technology Vol.49 No.1

To study the effects of zirconium (Zr) addition on the microstructure, hardness and the tensile properties of oxide dispersion strengthened (ODS) ferriticemartensitic steels, two kinds of 9Cr-ODS ferriticemartensitic steels with nominal compositions (wt.%) of Fe-9Cr- 2W-0.3Y2O3 and Fe-9Cr-2W-0.3Zr-0.3Y2O3 were fabricated by the mechanical alloying (MA) of premixed powders and then consolidated by hot isostatic pressing (HIP) techniques. The experimental results showed that the average grain size decreases with Zr addition. The trigonal d-phase Y4Zr3O12 oxides and body-centered cubic Y2O3 oxides are formed in the 9Cr-Zr-ODS steel and 9Cr non-Zr ODS steel, respectively, and the average size of Y4Zr3O12 particles is much smaller than that of Y2O3. The dispersion morphology of the oxide particles in 9Cr-Zr-ODS steel is significantly improved and the number density is 1.1 × 1023/m3 with Zr addition. The 9Cr-Zr-ODS steel shows much higher tensile ductility, ultimate tensile strength and Vickers hardness at the same time.

Removal of sudan dyes from aqueous solution by magnetic carbon nanotubes: Equilibrium, kinetic and thermodynamic studies

Xiaoshan Sun,Haijian Ou,Changfeng Miao,Ligang Chen 한국공업화학회 2015 Journal of Industrial and Engineering Chemistry Vol.22 No.-

In this study, magnetic carbon nanotubes (MCNTs) have been synthesized by hydrothermal synthesis ofFe3O4 nanoparticles onto carbon nanotubes, and characterized by Fourier transform infraredspectroscopy, transmission electron microscope and physical property measurement system. Theywere used as adsorbents for the removal of sudan I, sudan II, sudan III, and sudan IV from aqueoussolution. The effects of experimental parameters on adsorption were fully studied. The results showedthat 5 mg MCNTs can remove sudan dyes sufficiently from 20 mL aqueous solution within 60 min at pHin the range of 4–7. Moreover, the existence of NaCl favored the adsorption. The sorbents can be reusedmore than ten times with 2% acetic acid ethanol as desorption solution. The equilibrium, kinetic andthermodynamic studies were investigated. The resultant kinetic data were well described by the pseudosecond-order model. The Freundlich model fitted sudan dyes sorption isotherms better than theLangmuir model. The thermodynamic data calculated from the temperature dependent sorptionisotherms demonstrated that sudan dyes sorption on the MCNTs was a spontaneous process.

E-Commerce System Based on Information Ecology Research

Dan Sun,Haijian Zhang 보안공학연구지원센터 2016 International Journal of u- and e- Service, Scienc Vol.9 No.7

With the development of information technology, electronic commerce is closely related to People's Daily lives. To improve the efficiency of electric information management has become the key to the development of electronic commerce. Ecological theory and information science as new areas of cross, based on the basic theory of information ecology to build e-commerce system, formulate the related policy, by analyzing the feasibility of the system has better.

Preparation of the Water-Soluble Fluorene-Containing Fluorescent Polymer by One-Pot Method

Yuan Wang,Hongchi Zhao,Haijian Tan,Xiaomeng Li,Yunxia Qian,Libin Bai,Yonggang Wu,Shufang Lv 한국고분자학회 2015 Macromolecular Research Vol.23 No.10

A water-soluble fluorescent polymer, 2,7-di{4'-[3''-(S-poly(acryloyl ethylene diamine hydrochloride)-2'''- methyl propionic acid)propionyloxy hexyloxy]phenyl}-9,9-di(n-octyl)fluorene (P3) with regular and ordered structure, was designed and synthesized with high conversion using click reaction between thiols and carbon-carbon double bonds. Because the S-H bond is relatively weak, thiol groups are subject to rapid oxidation during purification and storage and thereby result in the low conversion in the following click reaction. To circumvent this limitation, the synthesis of thiol groups and click reaction were simultaneously performed in one system (one-pot method). The intermediate products P1 (S-1-dodecyl-S'-[poly(N-Boc-acryloyl ethylene diamine)-2'-methyl propionic acid]trithiocarbonate) and M2 (2,7-di[4-(acryloyloxy hexyloxy)phenyl]-9,9-di(n-octyl)fluorene) were prepared via reversible addition fragmentation chain transfer (RAFT) polymerization and Williamson synthesis, respectively. Then, 2,7- di{4'-[3''-(S-poly(N-Boc-acryloyl ethylene diamine)-2'''-methyl propionic acid)propionyloxy hexyloxy]phenyl}- 9,9-di(n-octyl)fluorene (P2) was synthesized with high conversion (83%) by employing a click reaction with P1 and M2 as starting materials. Finally, water-soluble fluorescent polymer P3 was obtained after the deprotection of P2. M2, P1, P2 and P3 were characterized by Fourier transform infrared (FTIR) spectrum, nuclear magnetic resonance (NMR), high-resolution mass spectroscopy (MS), gel permeation chromatograph (GPC), UV-Visible (UV-Vis) spectrum, and fluorescence, respectively. The results revealed that P3 displayed good solubility in water and not only exhibited a blue fluorescence emission band in water but also had a similar photoluminescent spectra to those of M2 and P2 in dichloromethane. The fluorescence quantum yield of P3 in aqueous solution could reach 0.10. In addition, the result of cell cytotoxicity indicates that P3 has low cytotoxicity and exhibits potential for biomedical applications. This work provides a new insight into the study of water-soluble fluorescent polymer.

Investigation on mechanical behavior and crack coalescence of sandstone specimens containing fissure-hole combined flaws under uniaxial compression

Qian Yin,Hongwen Jing,Haijian Su 한국지질과학협의회 2018 Geosciences Journal Vol.22 No.5

This study focuses on the effect of pre-existing flaw geometry on mechanical behavior and crack coalescence modes of sandstone specimens containing combined flaws with different fissure angle, ligament length and fissure length under uniaxial compression. The flaw geometry is a combination of a single hole and an inclined fissure underneath, which is generated by a high pressure water-jet cutting machine and is different from that reported in previous studies. The effect of flaw geometry on mechanical behavior of sandstone specimens is analyzed. Basically, mechanical parameters including the peak strength, peak axial strain, elastic modulus and secant Young’s modulus for the flawed specimens are lower than those for the intact specimens, with the reduction extent related to the fissure angle, ligament length and fissure length. Variation trends of the crack initiation stress for all tested cases are studied. Initiated crack types and cracking modes also depend on the combined flaws geometry. For the flawed specimens with a small fissure angle, ligament length or fissure length, cracking modes are generally characterized by cracks initiated from the hole-wall and evolved to the specimen boundary. However, when the fissure angle, ligament length or fissure length is increased, cracks initiated from both the hole-wall and fissure tips produce the main failure planes, accompanied by a free-standing “triangular prism structure” within the specimens. Numerical simulations using RFPA2D (Rock Failure Process Analysis in two dimensions) are carried out on the flawed sandstone specimens and agree well with the experimental results in the peak strength and overall cracking behavior.

Current Status of Serum Insulin and C-Peptide Measurement in Clinical Laboratories: Experience from 94 Laboratories in China

Zhou Weiyan,Deng Yuhang,Zhao Haijian,Zhang Chuanbao 대한진단검사의학회 2022 Annals of Laboratory Medicine Vol.42 No.4

Background: Accurate measurements of serum insulin and C-peptide are needed for the therapy and classification of diabetes. This study investigated the status of serum insulin and C-peptide measurements in China by analyzing the results of five pooled serum samples measured in 94 laboratories. Methods: Patient serum samples were pooled into five groups according to insulin and C-peptide concentrations and measured in 94 laboratories using different measurement systems. The inter- and intra-laboratory %CV as well as inter- and intra-measurement system %CV were calculated to assess the status of insulin and C-peptide measurements. To verify whether the disagreement between laboratories was due to different calibrators, as reported in previous studies, one low-level and one high-level sample extracted from the five pooled serum samples were used to recalibrate clinical measurement systems. Results: The mean intra-laboratory, intra-measurement system, inter-laboratory, and inter-measurement system %CVs were 2.7%, 4.8%, 21.8%, and 22.4%, respectively, for insulin and 2.3%, 6.7%, 16.4%, and 24.5%, respectively, for C-peptide. The inter- and intra-laboratory %CVs for insulin decreased with increasing concentration. After recalibration with low- and high-level samples, the mean inter-measurement %CV decreased from 22.4% to 17.2% for insulin and from 24.5% to 5.7% for C-peptide. Conclusions: The intra-laboratory and intra-measurement system imprecision values are satisfactory for serum insulin and C-peptide measurements. However, the results from laboratories using different measurement systems were not comparable, and there is still much work needed to achieve the standardization or harmonization of serum insulin and C-peptide measurements.

Commutability Assessment of Processed Human Plasma Samples for Normetanephrine and Metanephrine Measurements Based on the Candidate Reference Measurement Procedure

Deng Yuhang,Liu Qingxiang,Liu Zhenni,Zhao Haijian,Zhou Weiyan,Zhang Chuanbao 대한진단검사의학회 2022 Annals of Laboratory Medicine Vol.42 No.5

Background: To identify candidate external quality assessment (EQA) materials for normetanephrine and metanephrine measurements, we assessed the commutability of eight processed human plasma samples. The agreement between routine assays and the candidate reference measurement procedure (cRMP) was also evaluated. Methods: Fifty-three clinical samples and eight processed plasma samples were prepared. The processed samples included pooled and individual plasma samples spiked with pure normetanephrine and metanephrine and non-spiked pooled and individual plasma samples. The clinical and processed samples were subjected to four routine isotope dilution tandem mass spectrometry assays and cRMP. Commutability was assessed based on two approaches recommended by the CLSI and International Federation of Clinical Chemistry (IFCC). Passing–Bablok regression and Bland–Altman analysis were used to evaluate the agreement between the routine assays and cRMP. Results: The commutability results of the CLSI approach were better than those of the IFCC approach. For the CLSI approach, spiked individual plasma samples and spiked high-concentration pooled plasma samples were commutable for all routine assays for both analytes. The non-spiked pooled plasma sample was commutable for two out of four routine assays for metanephrine and three out of four routine assays for normetanephrine. The agreement between the routine assays and the cRMP was satisfactory, except for one routine assay showing significant bias. Conclusions: High-concentration spiked pooled plasma samples and spiked individual plasma samples are candidate EQA materials for normetanephrine and metanephrine measurements.

A putative pathogen-resistant regulatory pathway between MicroRNAs and candidate target genes in maize

Jian Gao,Mao Luo,Chun Zhang,Hua Peng,Haijian Lin,Yaou shen,Maojun Zhao,Guangtang Pan,Zhiming Zhang 한국식물학회 2015 Journal of Plant Biology Vol.58 No.4

MicroRNAs (miRNAs) are a family of small non-coding RNAs that, in most cases, negatively regulate gene expression at the post-transcriptional level. Plant miRNAs have been implicated in developmental processes and adaptation to environmental stress including biotic and abiotic stresses. Here, we report a comprehensive analysis of miRNAs and associated target genes under banded leaf and sheath blight (BLSB) stress caused by R. solani in maize. Eight differentially expressed miRNAs were randomly selected from deep sequencing results and validated by qRT-PCR together with their putative target genes, most of which are transcription factors as well as metabolic genes involved in auxin signaling. The results revealed that majorities of the analyzed miRNAs show an inverse correlation with their corresponding predicted target genes. In addition, a putative regulatory network of miRNAs-mRNAs responsive to R. solani was constructed. This study provides insight into the regulatory functions of miRNAs, thereby expanding our knowledge of the molecular mechanisms of pathogen resistance.

MULTIVARIATE EFFECTIVENESS OF ECOLANE AND ECOHMI BASED COOPERATIVE VEHICLE-INFRASTRUCTURE SYSTEM

Qiang Fu,Yiping Wu,Xiaohua Zhao,Yang Bian,Li HaijianLi 한국자동차공학회 2023 International journal of automotive technology Vol.24 No.1

The cooperative vehicle-infrastructure system (CVIS) offers opportunities to further enhance the potential of energy saving and emission reduction for eco-driving. However, it is still not clear about the effectiveness of CVIS on promoting eco-driving nor the multivariate effectiveness of CVIS designed for eco-driving on traffic flow and safety characteristics. A dedicated ecological lane (Ecolane) and ecological human-machine-interaction (EcoHMI) based CVIS (Ecolane-HMI-CVIS) were developed based on driving simulator technology. An experiment of 35 participants was conducted to study eco-driving behavior and final utility to identify the influence of Ecolane-HMI-CVIS. The results indicated that the Ecolane-HMI-CVIS enhanced eco-driving behavior and reduced emission, with CO and NOX significantly reduced by 10.72 % and 9.83 % respectively. The Ecolane-HMI-CVIS reduced the headway and promoted vehicle operation stability, ordering, and improved traffic capacity about 10 %. No negative impact of Ecolane-HMI-CVIS was observed on traffic safety. This study developed a test platform based on driving simulator to explore the multivariate influence of Ecolane-HMI-CVIS. In addition to analyzing the overall effect of Ecolane-HMI-CVIS during the whole experimental section, its detailed influence at each key zone and in spatial change process were also analyzed. This research contributed to better understanding of the working mechanism and effectiveness of Ecolane-HMI-CVIS, and provide technical and policy references of CVIS based eco-driving for traffic management departments.

Association of multiple anthropometric indices with in 944,760 elderly Chinese people

Lirong Dong,Yuanyuan Wang,Jinshui Xu,Yang Zhou,Guiju Sun,Dakang Ji,Haijian Guo,Baoli Zhu 한국역학회 2023 Epidemiology and Health Vol.45 No.-

OBJECTIVES: The aims of this study were to update the latest data on the prevalence of hypertension (HTN) in the elderly Chinese population and to assess relationships between new anthropometric indices and HTN. METHODS: Data were obtained from the Basic Public Health Service (BPHS) survey for Jiangsu Province, China. A total of 944,760 people aged 65 years and older were included in this study. Blood pressure was measured by trained investigators. Body weight, body mass index (BMI), waist circumference (WC), waist-to-height ratio (WtHR), conicity index (COI), body roundness index (BRI), and a body shape index (ABSI) were included in the analysis as anthropometric indices. Logistic regression analysis and restricted cubic splines were used to evaluate the association of anthropometric indices with HTN. RESULTS: The prevalence of HTN among elderly residents of Jiangsu Province was 64.7% (95% confidence interval, 64.6 to 64.8). After adjusting for multiple covariates, all anthropometric indices except ABSI showed significant non-linear positive dose-response associations with HTN across sex (pnonlinear<0.001). Among participants with BMI <28 kg/m2, abnormal weight, WC, WtHR, BRI, COI, and ABSI were positively associated with HTN. CONCLUSIONS: The prevalence of HTN in the elderly in Jiangsu Province is gradually increasing. It is necessary to consider the combination of ABSI and COI with BMI for screening elderly individuals for HTN in follow-up prospective studies.