Processing, microstructure and mechanical properties of porous silicon nitride by a slip casting method using petroleum coke as pore former

Huan-Rui Wang,Ji-Qiang Gao,Fang-Li Yu,Yuan Li,Jian-Feng Yang 한양대학교 세라믹연구소 2009 Journal of Ceramic Processing Research Vol.10 No.6

In this study, porous Si3N4 ceramics were obtained by a slip casting method which would be easier applied in industry. The most stable and dispersing aqueous suspension was obtained from a solid slurry content of 56.2%, a carboxymethyl cellulose concentration of 0.3% as the adhesive and 0.05% glycerol as the defoamer. Petroleum coke was used as pore-former, and at the same time, it was helpful for the stability of the suspension. The burning-out of the petroleum coke seemed to be an economical way for increasing the porosity of porous Si3N4. After sintering at 1,800℃ for 2 h, samples with a pore size about 10 μm, porosities of 45-60%, and flexural strength of 52.0-112.1MPa were obtained. In this study, porous Si3N4 ceramics were obtained by a slip casting method which would be easier applied in industry. The most stable and dispersing aqueous suspension was obtained from a solid slurry content of 56.2%, a carboxymethyl cellulose concentration of 0.3% as the adhesive and 0.05% glycerol as the defoamer. Petroleum coke was used as pore-former, and at the same time, it was helpful for the stability of the suspension. The burning-out of the petroleum coke seemed to be an economical way for increasing the porosity of porous Si3N4. After sintering at 1,800℃ for 2 h, samples with a pore size about 10 μm, porosities of 45-60%, and flexural strength of 52.0-112.1MPa were obtained.

Association Between Green Tea and Colorectal Cancer Risk: A Meta-analysis of 13 Case-control Studies

Wang, Xue-Jun,Zeng, Xian-Tao,Duan, Xiao-Li,Zeng, Huan-Chao,Shen, Rui,Zhou, Ping Asian Pacific Journal of Cancer Prevention 2012 Asian Pacific journal of cancer prevention Vol.13 No.7

Objective: Experimental studies have suggested green tea to be a chemopreventive agent for colorectal cancer, and many studies have examined possible associations. However, the conclusions were inconsistent or even contradictory, so we performed a meta-analysis based on published case-control studies to explore if green tea is indeed a protective factor. Methods: PubMed was searched up to May $10^{th}$, 2012 for relevant studies, and references of included studies were manually searched. Finally 13 eligible studies, involving 12,636 cases and 38,419 controls were identified. After data extraction, a meta-analysis was performed using CMA v2 software. Results: The results indicated there may be a weak but not statistically significant reduced risk of colorectal cancer with high dose of green tea intake (OR=0.95, 95% CI:0.81-1.11, p=0.490.69-0.98). This protective effect was also found in all subgroups, except in American and European populations. Sensitivity analysis indicated the result to be robust. Publication bias was not detected by either funnel plot or Egger tests. Conclusion: The results of this meta-analysis indicate a weak lower tendency for colorectal cancer development with green tea consumption, but available epidemiologic data are insufficient to conclude that green tea may protect against colorectal cancer in humans.

Analysis of Death Causes of In-patients with Malignant Tumors in Sichuan Cancer Hospital of China from 2002 to 2012

Wang, Xiao,Song, Zheng-Fang,Xie, Rui-Meng,Pei, Jiao,Xiang, Ming-Fei,Wang, Huan Asian Pacific Journal of Cancer Prevention 2013 Asian Pacific journal of cancer prevention Vol.14 No.7

Objectives: To analyze underlying disease, fatality rate and the major causes of death of in-patients with malignant tumors in Sichuan Cancer Hospital. Methods: Clinical data of in-patients from 2002 to 2012 were retrospectively analyzed. Results: The top 10 tumors (82.0%of the total) of the malignant tumors of the in-patients were lung, cervical, esophagus, breast, colorectal, nasopharynx, liver and gastric cancers, lymphomas and ovarian cancers. The overall fatality rate was 2.7% during these eleven years, 3.4% and 2.0% for male and females, respectively with statistical significance for the difference (${\chi}^2$=164.737, P<0.001). The top 10 death causes were lung cancer, liver cancer, colorectal cancer, esophagus cancer, gastric cancer, lymphoma, breast cancer, pancreatic cancer, ovarian cancer and nasopharynx cancer. In-patients with pancreatic cancer had the highest fatality rate (9.6%). There were different ranks of death causes in different sex groups and age groups. Conclusion: Prevention and control work of cancer should be enhanced not only for cancers with high incidence such as lung cancer, esophageal cancer but also for the cancers which have low incidence but high fatality rate, such as pancreatic cancer and gallbladder cancer, which would help to improve the survival rate and quality of life of cancer patients in the future.

Role of Alkaline Serine Protease, Asp, in Vibrio alginolyticus Virulence and Regulation of Its Expression by LuxO-LuxR Regulatory System

Hao Peng Rui,Qin Liu,Qi Yao Wang,Yue Ma,Huan Liu,Cun Bin Shi,Yuan Xing Zhang 한국미생물 · 생명공학회 2009 Journal of microbiology and biotechnology Vol.19 No.5

Heavy concrete shielding properties for carbon therapy

Jin-Long Wang,Jiade J Lu,Da-Jun Ding,Wen-Hua Jiang,Ya-Dong Li,Rui Qiu,Hui Zhang,Xiao-Zhong Wang,Huo-Sheng Ruan,Yan-Bing Teng,Xiao-Guang Wu,Yun Zheng,Zi-Hao Zhao,Kai-Zhong Liao,Huan-Cheng Mai,Xiao-Dong Korean Nuclear Society 2023 Nuclear Engineering and Technology Vol.55 No.6

As medical facilities are usually built at urban areas, special concrete aggregates and evaluation methods are needed to optimize the design of concrete walls by balancing density, thickness, material composition, cost, and other factors. Carbon treatment rooms require a high radiation shielding requirement, as the neutron yield from carbon therapy is much higher than the neutron yield of protons. In this case study, the maximum carbon energy is 430 MeV/u and the maximum current is 0.27 nA from a hybrid particle therapy system. Hospital or facility construction should consider this requirement to design a special heavy concrete. In this work, magnetite is adopted as the major aggregate. Density is determined mainly by the major aggregate content of magnetite, and a heavy concrete test block was constructed for structural tests. The compressive strength is 35.7 MPa. The density ranges from 3.65 g/cm³ to 4.14 g/cm³, and the iron mass content ranges from 53.78% to 60.38% from the 12 cored sample measurements. It was found that there is a linear relationship between density and iron content, and mixing impurities should be the major reason leading to the nonuniform element and density distribution. The effect of this nonuniformity on radiation shielding properties for a carbon treatment room is investigated by three groups of Monte Carlo simulations. Higher density dominates to reduce shielding thickness. However, a higher content of high-Z elements will weaken the shielding strength, especially at a lower dose rate threshold and vice versa. The weakened side effect of a high iron content on the shielding property is obvious at 2.5 µSv=h. Therefore, we should not blindly pursue high Z content in engineering. If the thickness is constrained to 2 m, then the density can be reduced to 3.3 g/cm³, which will save cost by reducing the magnetite composition with 50.44% iron content. If a higher density of 3.9 g/cm³ with 57.65% iron content is selected for construction, then the thickness of the wall can be reduced to 174.2 cm, which will save space for equipment installation.

Evaluation of suitable qRT-PCR normalization genes for various citrus rootstocks

He Wen,Xie Rui,Li Huan,Wang Yan,Chen Qing,Lin Yuanxiu,Zhang Yunting,Luo Ya,Zhang Yong,Tang Haoru,Wang Xiaorong 한국식물생명공학회 2022 Plant biotechnology reports Vol.16 No.1

Citrus rootstock can modify plant growth and enhance stress resistance. There are many genotypes and species used as citrus rootstocks. Although multiple citrus rootstocks whole genome sequence and transcriptome databases have previously been published, no suitable internal reference genes have been investigated for standardization of gene expression via quantitative real-time PCR. Here we reported the first systematic and comprehensive analysis of reference genes for quantitative real- time PCR standardization in various citrus rootstocks. The expression stability of ten candidate reference genes in diverse sample subsets of flooding, drought, alkaline and cold treatments was evaluated using four statistical algorithms, geNorm, NormFinder, BestKeeper and ΔCt method. The results demonstrated that the expression stability of reference genes varied under different experimental conditions. In addition, normalization of gene expression of 9-cis-epoxycarotenoid dioxygenase 3 (NCED 3), involved in abscisic acid biosynthesis, was conducted to further confirm the reliability of the reference genes. Overall, EF-1α, DIM 1, GAPC and UBC expressed much more stably. ACTIN and GAPDH were not recommended for normalization in given experimental conditions due to low stability. Our main contribution was to identify reference genes with suitable and stable expression in citrus rootstocks varied across selected experimental conditions. Furthermore, these results will provide valuable information for future research on citrus rootstocks.

Adaptive Dynamic Output-feedback Control for Chemical Continuous Stirred Tank Reactor System with Nonlinear Uncertainties and Multiple Time-delays

Wei Zheng,Hong-Bin Wang,Shu-Huan Wen,Hong-Rui Wang,Zhi-Ming Zhang 제어·로봇·시스템학회 2018 International Journal of Control, Automation, and Vol.16 No.4

This paper addresses the dynamic-output-feedback control problem for a class of nonlinear system with nonlinear uncertainties and multiple time-delays. Compared with the previous work, the time delay parameters of the system are both multiple and time-varying, and the results are further extended to the chemical continuous stirred tank reactor (CSTR) case. First, the system is decomposed into two subsystems based on the output and input matrix. Secondly, a dynamic compensator is designed for the first subsystem, and the output feedback controller is further employed based on the second subsystem and the compensator. Moreover, by using the introduced LyapunovKrasovskii functional, it can be seen that the solutions of the resultant closed-loop system converge to an adjustable bounded region. In this paper, the uncertainties are in the nonlinear form and bounded by nonlinear functions with unknown gains. And the control design conditions are relaxed because of the developed dynamic compensator. Finally, the simulations for a chemical (CSTR) case are performed to show the effectiveness of the main results.

ANXA2 Regulates the Behavior of SGC-7901 Cells

Sun, Meng-Yao,Xing, Rui-Huan,Gao, Xiao-Jie,Yu, Xiang,He, Hui-Min,Gao, Ning,Shi, Hong-Yan,Hu, Yan-Yan,Wang, Qi-Xuan,Xu, Jin-Hui,Hou, Ying-Chun Asian Pacific Journal of Cancer Prevention 2013 Asian Pacific journal of cancer prevention Vol.14 No.10

ANXA2, a member of the annexin family, is overexpressed and plays important roles in tumor development. However, the significance of ANXA2 expression in gastric carcinoma has not been clarified.To elucidate its roles in growth of gastric cancer, ANXA2 expression in SGC-7901 cells was inhibited with a designated siRNA, then cell proliferation, cell cycling, apoptosis and motility were determined by MTT assay, flow cytometry, Hoechst 33342 staining and wound healing assay, respectively. To further assess the behavior of ANXA2 deleted SGC-7901 cells, changes of microstructures were observed under fluorescence microscopy, laser scanning confocal microscopy and electron microscopy. We found that inhibition of ANXA2 expression caused cell proliferation to decrease significantly with G1 arrest, motility to be reduced with changes in pseudopodia/filopodia structure and F-actin and ${\beta}$-tubulin expression, and apoptosis to be enhanced albeit without significance. At the same time, ANXA2 deletion resulted in fewer pseudopodia/filopodia, non-stained areas were increased, contact inhibition among cells reappeared, and expression of F-actin and ${\beta}$-tubulin was decreased, with induction of polymerized disassembled forms. Taken together, these data suggest that ANXA2 overexpression is important to maintain the malignancy of cancer cells, and this member of the annexin family has potential to be considered as a target for the gene therapy of gastric carcinoma.

Phenolic constituents from Parakmeria yunnanensis and their anti-HIV-1 activity

Shan-Zhai Shang,Huan Chen,Cheng-Qin Liang,Zhong-Hua Gao,Xue Du,Rui-Rui Wang,Yi-Ming Shi,Yong-Tang Zheng,Wei-Lie Xiao,Han Dong Sun 대한약학회 2013 Archives of Pharmacal Research Vol.36 No.10

Three new phenolic compounds, yunnanensinsA–C (1–3), together with fourteen known ones (4–17),were isolated from the leaves and stems of Parakmeriayunnanensis. The structures of new compounds wereestablished on the basis of extensive spectroscopic analyses. Several compounds showed weak anti-HIV-1 activity.

Phase separation phenomena and thermodynamics of octylphenol polyoxyethylene ether in micellar solutions: Effect of high concentration of inorganic salts and linear correlation

Dan Ni Li,Jing Huang,Zhao Hua Ren,Rui Sheng,Zheng Bo Qian,Bei Bei Li,Xiao Feng Quan,Ye Xi Zhang,Jun Ru Wang,Huan Tian 한국공업화학회 2021 Journal of Industrial and Engineering Chemistry Vol.99 No.-

The phase separationphenomena or cloud points (CP) behaviorof nonionic octylphenol polyoxyethylene etherwith oxyethylene glycol ether unit of 15 (OP-15) were investigated in aqueous micellar solutions containinghigh concentrations of inorganic salts including NaCl, KCl, MgCl2, CaCl2, BaCl2, AlCl3, FeCl3, Na2SO4and Na2SiO3. The change in CP induced by salts and its mechanism are discussed theoretically. In aqueous solutionscontaining high concentration of salt, for thefirst time the linear relationship between CP and saltconcentrationiswellestablishedtocharacterizethedepressionofCP.Basedonpseudophaseseparationmodel,thermodynamic parameters are estimated and adopted to further describe the phase separation process andthe interactions between OP-15 molecules or the OP-15/water interactions. Thermodynamic parametersincluding standard Gibbs energy change (DG0CP), enthalpy change (DH0CP) and entropy change (DS0CP)indicate that the additions of different salts result in the change in entropy-driven nonspontaneousprocess of phase separation. These data, which are from the compensation temperatures and the changeof molar heat capacity, also prove that different ions induce the change in the interactions betweensurfactant molecules or the surfactant–water interaction and thus affect the depression of CP. Thesefindings help with understanding the effect of inorganic salts, especially the high concentration of salt, onCP of nonionic surfactant and then broadening the application of nonionic surfactant based on CP such asthe extraction of biomaterials in biological samples derived from animals or plants, etc.