Microstructure and Magnetic Properties of Nanocomposite Sm₂Fe15Ga₂Cx / α-Fe Permanent Magnets

Zhao-hua Cheng 한국자기학회 2003 Journal of Magnetics Vol.8 No.1

In our previous work, microstructure and magnetic properties of two-phase exchange-coupled Sm₂Fe_(15)Ga₂Cx/α-Fe nanocomposites have been investigated by means of x-ray diffraction, transmission electron microscopy and magnetization measurement. It was found the exchange coupling between the magnetically hard phase Sm₂Fe_(15)Ga₂Cx and the magnetically soft one α-Fe results in an enhancement of the remanence. The sizes of crystallites of both phases are, however, much larger than the Bloch domain-wall width of the magnetically hard phase. This microstructure gives rise to a concave demagnetization curve and consequently reduces the maximum energy product. In order to improve their magnetic properties, a few percent of Zr, which may be effective to refine the microstructure through rapid quenching, was introduced into the nanocomposites. The addition of Zr was found to improve the magnetic properties significantly. Under optimum heat-treatment conditions, the remanence, coercivity and maximum energy product increase from 0.65 T, 0.48 T and 50 kJ/㎥ for the Zr-free sample to 0.72 T, 0.77 T and 71.6 kJ/㎥ for the 1 at.% Zr-containing one, respectively. The improvements of magnetic properties are due to the refinement of microstructure by the addition of Zr.

Microstructure and magnetic properties of nanocomposite permanent magnetic materials

Zhao-hua Cheng 한국자기학회 2002 한국자기학회 학술연구발표회 논문개요집 Vol.12 No.2

Micellization behavior of binary mixtures of amino sulfonate amphoteric surfactant with different octylphenol polyoxyethylene ethers in aqueous salt solution: Both cationic and hydrophilic effects

Zhao Hua Ren,Jing Huang,Yue Luo,Yan Cheng Zheng,Ping Mei,Lu Lai,Yan Ling Chang 한국공업화학회 2016 Journal of Industrial and Engineering Chemistry Vol.36 No.-

The effect of different valent inorganic cations and the hydrophilic group of surfactant on themicellization behavior of binary surfactant mixtures constituted by an amphoteric surfactant, sodium3-(N-dodecyl ethylenediamino)-2-hydropropyl sulfonate (C12AS), and three nonionic surfactantsoctylphenol polyoxyethylene ether (OP-n) with different numbers of oxyethylene glycol ethers (n),namely, OP-10, OP-7, and OP-4 was investigated in aqueous solution. These inorganic cations includeNa+, K+, Mg2+, Ca2+, Ba2+, Al3+ and Fe3+. Both the tensiometry and the UV–vis spectrophotometry usingpyrene as a probe were adopted to determine the critical micelle concentrations (cmc) of individual ormixed surfactants. Interaction parameters between two surfactants and other parameters were obtainedbased on the regular solution theory, the pseudophase separation model, Rubingh’s model, etc. Thermodynamic parameters including Gibbs energy of micellization and thermodynamic stability werealso calculated by both the equation proposed by Molyneux et al. and Maeda’s treatment, respectively. The effect of different valent cations on both the mixed cmc of surfactant mixtures and the molar fractionof C12AS in mixed micelle (X1) can be explained theoretically by the salting-out effect, electrostaticinteraction and steric effect. For three binary surfactant mixtures, the chain length of hydrophilic groupof surfactant results in different micellization behaviors. On adding salts, the interaction parametersshow that there exists a synergistic effect between two surfactants, and the effect increases withincreasing the ratio of valence (Z) and atom radius (R) of cation, especially, for the C12AS/OP-4 mixture. With increasing the Z/R value of cation, a deviation of X1 from the ideal value shows a divergence forthree binary surfactant mixtures because of different hydrophilicities of surfactant. Thermodynamicparameters indicate that the addition of cations with a large Z/R value can be contributive moreeffectively to the formation of stable mixed micelle than the case in the presence of cations with a smallZ/R value.

Bicluster and Pathway Enrichment Analysis of HCV-induced Cirrhosis and Hepatocellular Carcinoma

Cheng, Peng,Cheng, You,Su, Mei X.,Li, Dong,Zhao, Guo Z.,Gao, Hui,Li, Yan,Zhu, Jie Y.,Li, Hua,Zhang, Tao Asian Pacific Journal of Cancer Prevention 2012 Asian Pacific journal of cancer prevention Vol.13 No.8

Background: Hepatocellular carcinoma (HCC) is the sixth most common cancer worldwide and the most common form of liver cancer. However, while it is associated frequently with hepatitis C virus (HCV) there is only an elementary understanding of its molecular pathogenesis. Methods: To gain insight into the molecular mechanisms of HCV-induced hepatocarcinogenesis, we performed microarray analysis on 75 surgical liver samples from 48 HCV-infected patients. Results: There were 395 differentially expressed geness between cirrhotic samples and HCC samples. Of these, 125 genes were up-regulated and 270 genes were down-regulated. We performed pathway enrichment analysis and screened as described previously. Conclusions: The differentially expressed genes might be involved in hepatocarcinogenesis through upregulating the pathways of ECM-receptor interaction, focal adhesion, cell adhesion molecules and other cancer-related pathways, and downregulating the pathways of "complement and coagulation cascades". We hope our results could aid in seeking of therapeutic targets for HCV-induced hepatocellular carcinoma.

Alginate and Probiotics Synergistically Reversed Dextran Sulfate Sodium Salt (DSS)-Induced Gut Barrier Damage

Cheng Zhao,Qiongyuan Hu,Xiuwen Wu,Guopu Chen,Hua Wu,Jianan Ren 한국고분자학회 2019 Macromolecular Research Vol.27 No.9

Previous studies have established that sole probiotics or fibre could be used to relieve colitis. However, few studies evaluated the synergistical effect of fibre and probiotics in treating colitis. This study, examined the effect of alginate, one of the commonest biomaterials and dietary fibre, and/or probiotics on the gut barrier in colitis mice. A synergistical effect was found between alginate and probiotics in colitis. Dextran sulfate sodium salt (DSS), a chemical toxic substance, was used to induce colitis model. Body weight, oxidative stress, inflammatory factors, gut barrier, intestinal morphology and the apoptosis of intestine epithelial cells were analyzed. A combination of probiotics and alginate was used to analyze their synergistic effect. The results showed that the combination of alginate and probiotics had a better therapeutic effect on colitis than using them individually, and they protected the gut barrier from DSS induced oxidative stress. The combination exhibited a greater ability in reducing pro-inflammatory factors and protecting the gut barrier from further damage. The synergistic effect of alginate and probiotics provides a great prospect for biotherapy in bowel diseases and oral drug delivery system.

Comparison of the Gene Expression Profiles Between Smokers With and Without Lung Cancer Using RNA-Seq

Cheng, Peng,Cheng, You,Li, Yan,Zhao, Zhenguo,Gao, Hui,Li, Dong,Li, Hua,Zhang, Tao Asian Pacific Journal of Cancer Prevention 2012 Asian Pacific journal of cancer prevention Vol.13 No.8

Lung cancer seriously threatens human health, so it is important to investigate gene expression changes in affected individuals in comparison with healthy people. Here we compared the gene expression profiles between smokers with and without lung cancer. We found that the majority of the expressed genes (threshold was set as 0.1 RPKM) were the same in the two samples, with a small portion of the remainder being unique to smokers with and without lung cancer. Expression distribution patterns showed that most of the genes in smokers with and without lung cancer are expressed at low or moderate levels. We also found that the expression levels of the genes in smokers with lung cancer were lower than in smokers without lung cancer in general. Then we detected 27 differentially expressed genes in smokers with versus without lung cancer, and these differentially expressed genes were foudn to be involved in diverse processes. Our study provided detail expression profiles and expression changes between smokers with and without lung cancer.

Isolation and Expression Analysis of a GDSL-Like Lipase Gene from Brassica napus L.

( Hua Ling ),( Jing Ya Zhao ),( Kai Jing Zuo ),( Cheng Xiang Qiu ),( Hong Yan Yao ),( Jie Qin ),( Xiao Fen Sun ),( Ke Xuan Tang ) 생화학분자생물학회 2006 BMB Reports Vol.39 No.3

Interaction and micellar behavior of ternary mixture of amphoteric amino sulfonate surfactant with traditional anionic and nonionic surfactants: Effect of hydrophilicity

Qing Hua Zhang,Rui Sheng,Zhao Hua Ren,Jing Huang,Yun Xiao Wang,Ben Ru Wang,Xi Lei Huang,Qin Cheng,Xue Mei Wu,Tong Bo Wang 한국공업화학회 2023 Journal of Industrial and Engineering Chemistry Vol.120 No.-

The micellization and the molecular interaction behaviors for two ternary mixtures constituted by anamphoteric sodium 3-(n-dodecyl ethylenediamino)-2-hydroxypropyl sulfonate (C12AS), an anionicsodium dodecylbenzene sulfonate (SDBS) and a nonionic octylphenol polyoxyethylated ether with thenumber (n) of oxyethylene glycol ethers OP-n (n = 10 or 7) in aqueous solution were investigated usingthe tensiometry and the effect of hydrophilicity on them was also discussed. In the framework of pseudophaseseparation model and based on the regular solution theory, the related micellization parametersincluding the mixed critical micelle concentration (cmc) values in the ideal and real cases, the activitycoefficients and the compositions in mixed micelle, etc. and thermodynamic parameters were estimatedby the Clint’s model and the Rubingh’ model. The mixed cmc value is dependent on the composition inaqueous solution and influenced by the hydrophilicity of nonionic surfactant. With increasing the nonionicin ternary mixture, the mixed cmc value is initially decreased and then slightly rise. An increasingin the hydrophilicity of nonionic will make the minimum value of mixed cmc be increased from1.299 mM to 1.705 mM. The resulting phenomena can be explained reasonably by the electrostatic effect,the steric hindrance, the hydrogen bonding, etc. Thermodynamic data indicate that the contribution ofentropy or enthalpy plays a vital role on the spontaneous process of micellization and the share ofentropy or enthalpy in free energy change is dependent largely on the amount of nonionic surfactantand the hydrophilicity. In ternary mixtures of C12AS/SDBS/OP-10, an increase in an amount of OP-10 willinduce the change from the enthalpy-driven micellization process to the entropically favorable process. Once an abundant amount of OP-7 is added, while, the enthalpy will make a main contribution on themicellization process, which can be described by the drop in the share of entropy at the composition(0.6970/0.0000/0.3030) of ternary mixture from 0.6478 to 0.4901. These findings will help with understandingthe molecular interaction behavior for the ternary surfactant mixture and the effect of the additionof nonionic surfactant and its hydrophilicity.

Study on host plants for reproduction of Chilo suppressalis

Wei-Hua Jiang,Hai-Dong Li,Xiong-Feng Cheng,Jian-Ren Ye,Yong-Bin Feng,Zhao-Jun Han 한국응용곤충학회 2015 Journal of Asia-Pacific Entomology Vol.18 No.3

The rice stem borer, Chilo suppressalis, is generally considered to be a polyphagous pest. The current study challenges this view by investigating its oviposition preference, larval survival and development on different host plants under both laboratory and field conditions. Rice and water-oat populations of the borer inhabiting on corresponding plants respectively have partial reproductive isolation based on previous studies. In a laboratory multiple-choice test, C. suppressalis adults from rice population laid most of eggs on water-oat (46.5% of total eggs) and rice (43.8%), with very fewlaid onwheat (3.6%), sugarcane (4.0%) andmaize (2.0%). Field surveys supported the laboratory study and found no egg on the plants other than rice and water-oat. Neonate inoculation experiments performed in field and laboratory showed that larval survival rate was much higher on rice (49.1%–51.2%) and wheat (36.5%–44.1%) than that on water-oat (10.7%–10.8%), maize (1.2%–7.2%), sugarcane (0–1.5%) and weeds (2.4%). These results were discussed with the data reported from water-oat population and it was concluded that C. suppressalis is not a typical polyphagous pest. Rice population mainly reproduces on rice and use water-oat only as minor host, and water-oat population breeds better on water-oat than on rice as reported. Neither population could thrive on the other recorded host plants, which are used for the supplementary nutrition sources of larvae. These findings provide useful information for the development of control strategies to prevent C. suppressalis laying eggs on rice seedlings in early spring, hence effectively reducing population density of this pest in rice fields.

Effect of the Vacuum Heat Treatment on the Microstructure and Mechanical Properties of the Galvanized-Q235/AZ91D Bimetal Material Produced by Solid–Liquid Compound Casting

Jun Cheng,Jian‑hua Zhao,Dengzhi Zheng,Ke He,Yu Guo 대한금속·재료학회 2021 METALS AND MATERIALS International Vol.27 No.3

The galvanized-Q235/AZ91D bimetallic material was achieved via solid–liquid compound casting, and the effect of theheat treatment at 250 °C for 3 h on the microstructure and mechanical properties of the galvanized-Q235/AZ91D bimetallicmaterial were investigated. The interface zone in the galvanized-Q235/AZ91D was composed of three different layers whichwere the FeAl3+ α-Mg, (α-Mg + MgZn), and α-Mg + (α-Mg + MgZn) from the galvanized-Q235 to AZ91D, successively. After the heat treatment, the (α-Mg + MgZn) eutectic structure was transformed into Al5Mg11Zn4to promote the microhardnessfrom 139.2 HV to reach 298.8 HV. In addition, the α-Mg and (α-Mg + Mg12Al17) eutectic structure in AZ91D wereseparately transformed into (α-Mg + Al5Mg11Zn4) and Al5Mg11Zn4resulting in the increasement of microhardness, from59.5 to 173.4 HV and 294.2 HV, respectively. Moreover, the interfacial shear strength was changed from 11.23 to 24.63 MPadue to the formation of Al5Mg11Zn4and the vanishment of MgZn.