Synthesis and Properties of Cellulose-based Superabsorbent Hydrogel by a New Crosslinker

Heng-Xiang Li,Xin Tian,Luming Zhang,Leili Wang,Li’e Jin,Qing Cao 한국섬유공학회 2020 Fibers and polymers Vol.21 No.7

Cellulose-based superabsorbent hydrogel (SAH) has been successfully prepared by the grafting method withcellulose and sodium acrylate as well as aluminum hydroxide as a novel crosslinker. The factors influencing water absorptionsuch as the neutralization degree of acrylic acid (AA), the amount of initiator ammonium persulfate (APS) and crosslinker,and the proportion of cellulose to AA were investigated. The chemical structure and thermal behavior of the SAH wereanalyzed by fourier-transform infrared spectrometry, field-emission scanning electron microscopy, and thermal gravimetry,respectively. Results showed that the water absorbency of the SAH in distilled water and 0.9 wt% NaCl solution reached 922and 118 g/g when the mass ratio of cellulose to AA, APS to AA, Al(OH)3 to AA, and the neutralization degree of AA was39 wt%, 0.67 wt%, 0.89 %, and 76 %, respectively. Under the same condition, the hydrogel synthesized by traditionalcrosslinker N,N-methylenebisacrylamide was only 530 and 84 g/g in distilled water and 0.9 wt% NaCl solution, respectively. The mechanism of polymerization reaction was analyzed. And the cost and feasibility for the mass-producing the hydrogelwere analyzed.

Analysis of SCARA Robot Controller

Feng Cao,Xue-Heng Tao,Xin Zhao,Jin-Shi Lu 한국멀티미디어학회 2006 한국멀티미디어학회 국제학술대회 Vol.2006 No.-

The robot controller is one of the key parts in the robot. It has an important influence on the running of the robot, which in tum may affect the production. The principle of the controller, therefore, should be fully understood and mastered. no structure and working principle of Type of Panadac399 of SCARA Industry Robot is analyzed in this paper, which can provide references for the future design, mounting, debugging and improvement of the same type of robot controller or numerical control machines.

Study on horizontal diffusion of agent solutions in underground unsaturated soil: experiments and model simulations

Chenxi Cao,Deshun Yin,Guangjian Xiang,Heng Guo,Yunjie Chen 대한환경공학회 2021 Environmental Engineering Research Vol.26 No.3

Solute transport or water transport in unsaturated soil plays an important theoretical guiding role in remediation engineering. In order to study the diffusion of agent solutions in practical remediation engineering, the soil column experiments of unsaturated soil were carried out using the self-made laboratory test device. The effects of injection rate and soil pressure (confining pressure) on the solute diffusion in soil were studied. The experimental results show that the injection velocity has a great influence on the solute diffusion in soil, and the change in the diffusion rate is not proportional to the injection velocity. The effect of confining pressure on solute diffusion was first promoted and then suppressed. The fractal Richards equation (FRE) model was used to fit the water content curves. The results show that the FRE model has a fine fitting effect on this series of experiments, proving that it can provide model support for the simulation of solute diffusion in underground unsaturated soil. At the same time, the physical significance reflected by the fitting parameters can be used to analyze the mechanism of the experimental phenomena.

Magnetite for phosphorus removal in low concentration phosphorus-contained water body

Xiang, Heng,Liu, Chaoxiang,Pan, Ruiling,Han, Yun,Cao, Jing Techno-Press 2014 Advances in environmental research Vol.3 No.2

Magnetite was chosen as a typical adsorbent to study its phosphate adsorption capacity in water body with low concentration of phosphorus (below $2mg\;PL^{-1}$). Magnetite was collected from Luoyang City, Henan Province, China. In this research, three factors have been studied to describe the adsorption of phosphate on magnetite, which was solution concentration (concentration ranging from 0.1 to $2.5mg\;PL^{-1}$), suspension pH (1 to 13) and temperature (ranging from $10^{\circ}C$ to $40^{\circ}C$). In addition, the modified samples had been characterized with XRD and FE-SEM image. The results show that iron ions contains in magnetite were the main factors of phosphorus removal. The behavior of phosphorus adsorption to substrates could be fitted to both Langmuir and Freundlich isothermal adsorption equations in the low concentration phosphorus water. The theoretical saturated adsorption quantity of magnetite is 0.158 mg/g. pH has great influence on the phosphorus removal of magnetite ore by adsorption. And pH of 3 can receive the best results. While temperature has little effect on it. Magnetite was greatly effective for phosphorus removal in the column experiments, which is a more practical reflection of phosphorous removal combing the adsorption isotherm model and the breakthrough curves. According to the analysis of heavy metals release, the release of heavy metals was very low, they didn't produce the secondary pollution. The mechanism of uptake phosphate is in virtue of chemisorption between phosphate and ferric ion released by magnetite oxidation. The combined investigation of the magnetite showed that it was better substrate for water body with low concentration of phosphorus.

A Systemic Analysis of S-1 Regimens for Treatment of Patients with Colon Cancer

Zhang, En,Cao, Wei,Cheng, Chong,Huo, Bin-Liang,Wang, Yong-Heng Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.5

Background: Fluorouracil-based regimens have been widely accepted and recommended in the guidelines for treating patients with early or advanced staged colon cancer, although results are controversial. Here we performed a systemic analysis to evaluate the impact of S-1 based regimens on response and survival of patients with colon cancer. Methods: Clinical studies evaluating the impact of S-1 based regimens on response and survival of patients with colon cancer were identified using a predefined search strategy. Summary response rates (RRs) to treatment were calculated. Results: Six clinical studies which including 227 patients with advanced colorectal cancer were considered eligible for inclusion. Two studies were conducted using combination of S-1 and Oxaliplatin, and four studies featured S-1 and irinotecan. Systemic analysis showed that, in all patients, pooled RRs was 43.17%. Major adverse effects were hematological toxicities, gastrointestinal disturbance, neurosensory toxicity. No treatment related death occurred. Conclusion: This systemic analysis suggests that S-1 based regimens, both with oxaliplatin or irinotean are associated with acceptable response and toxicity in patients with colon cancer.

ST6GALNAC1 promotes the invasion and migration of breast cancer cells via the EMT pathway

Luo Yunzhao,Cao Heng,Lei Chuqi,Liu Jun 한국유전학회 2023 Genes & Genomics Vol.45 No.11

Background A specific sialyl-transferases called ST6GALNAC1 has been proven to up-regulate abnormal O‐glycosylation, which is strongly associated with tumorigenesis and cancer progression. However, the precise pathological outcome of ST6GALNAC1 expression in breast cancer cells remains unknown. Therefore, our study aims to investigate the functional role of ST6GALNAC1 and its impact on the epithelial-mesenchymal transition (EMT) pathway in breast cancer cells. Methods Plasmids with siRNA were used to construct ST6GALNAC1 knockoff (si-ST6GALNAC1) MDA-MB-231 and MDA-MB-453 cells, while lentiviruses were used to construct ST6GALNAC1 over-expression (oe-ST6GALNAC1) MCF-7 and BT474 cells. Transfer efficiency was verified by Western Blot. Then we selected transfected cells and assessed the changes in cell proliferation, invasion, migration, and EMT markers. Results The expression of ST6GALNAC1 significantly enhanced cell migration and invasion, which was confirmed by Wound Scratch Assay and Transwell Assay. Particularly, ST6GALNAC1 expression directly induced the EMT signaling pathway. E-cadherin was markedly decreased in oe-ST6GALNAC1 cells, accompanied by an up-regulation of mesenchymal markers including N-cadherin, snail, and ZEB1. However, no significant correlation was found between ST6GALNAC1 expression and cell proliferation. All of the outcomes were reversely validated in si-ST6GALNAC1 cells. Conclusions The expression of ST6GALNAC1 promotes cell migration and invasion probably by triggering the molecular process of the EMT pathway in breast cancer cells, which may provide new clues for designing novel molecular targeted drugs in breast cancer treatment.

Effect of hydraulic distribution on the stability of a plane slide rock slope under the nonlinear Barton-Bandis failure criterion

Zhao, Lian-Heng,Cao, Jingyuan,Zhang, Yingbin,Luo, Qiang Techno-Press 2015 Geomechanics & engineering Vol.8 No.3

In this paper, stabilities of a plane slide rock slope under different hydraulic distributions were studied based on the nonlinear Barton-Bandis (B-B) failure criterion. The influence of various parameters on the stability of rock slopes was analyzed. Parametric analysis indicated that studying the factor of safety (FS) of planar slide rock slopes using the B-B failure criterion is both simple and effective and that the effects of the basic friction angle of the joint (${\varphi}_b$), the joint roughness coefficient (JRC), and the joint compressive strength (JCS) on the FS of a planar slide rock slope are significant. Qualitatively, the influence of the JCS on the FS of a slope is small, whereas the influences of the ${\varphi}_b$ and the JRC are significant. The FS of the rock slope decreases as the water in a tension crack becomes deeper. This trend is more significant when the flow outlet is blocked, a situation that is particularly prevalent in regions with permafrost or seasonal frozen soil. Finally, the work is extended to study the reliability of the slope against plane failure according to the uncertainty from physical and mechanics parameters.

Mutually different tooth surface contact characteristics of a noncircular face gear with intersecting axes

Dawei Liu,Heng Li,Zhenzhen Lv,Yuetong Cao 대한기계학회 2023 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.37 No.4

The noncircular face gear (NFG) with intersecting axes is composed of a spur gear and a NFG, which can realize the reduced and variable-speed integrated transmission between any intersecting axes. To study the contact characteristics of NFG with intersecting axes, the mutually different tooth surface mathematical model of the NFG with intersecting axes was established, and a tooth surface analysis method based on rotational projection was innovatively proposed. By using this method, the distribution characteristics of contact traces on different tooth profiles can be accurately compared through establishing the comparison reference of the middle plane on gear teeth. At the same time, the effects of installation errors and eccentricity on the contact characteristics of tooth surface were analyzed in detail. Results demonstrate that the change in the same kind of installation error has the same effect on the offset direction of the contact traces on each gear tooth. Under the same installation error, changing the eccentricity of the NFG will cause different changes in the offset of the contact traces on each gear tooth. Finally, a gear transmission device of NFG with intersecting axes was designed and manufactured. The correctness of the contact model and the analysis results were proven by the gear pair rolling experiment, which provides a theoretical basis for the design and installation of NFG with intersecting axes.

Fault Detection Observer Design for Fuzzy Systems with Local Nonlinear Models via Fuzzy Lyapunov Function

Guojun Liu,Xiao-Heng Chang,Yong-Yan Cao 제어·로봇·시스템학회 2017 International Journal of Control, Automation, and Vol.15 No.5

This paper concerns with the problem of designing fault detection (FD) observer for Takagi-Sugeno (TS)fuzzy systems subject to local nonlinear models. Different from the quadratic Lyapunov function approaches,fuzzy Lyapunov function approach is applied to design the fault detection observer, and corresponding sufficientconditions are given in terms of linear matrix inequalities. In addition, combined with nonlinear local modelsscheme and slack variable technique, the T-S fuzzy systems have fewer fuzzy rules to reduce the computationalburden. Compared with the existing results, less conservative results on existence of fuzzy fault detection observersare derived. Moreover, the designed fuzzy fault detection observer not only guarantees the residual system stabilitybut also improves the H_ index estimation. It is noted that the H_ index is employed to measure the worst-cast faultsensitivity performance. Finally, a numerical simulation is given to illustrate the effectiveness of the designed faultdetection observer.

Ten-eleven translocation 1 mediating DNA demethylation regulates the proliferation of chicken primordial germ cells through the activation of Wnt4/β-catenin signaling pathway

Lu Yinglin,Li Ming,Cao Heng,Zhou Jing,Li Fan,Yu Debing,Yu Minli 아세아·태평양축산학회 2024 Animal Bioscience Vol.37 No.3

Objective: The objective of this study was to investigate the regulation relationship of Teneleven translocation 1 (Tet1) in DNA demethylation and the proliferation of primordial germ cells (PGCs) in chickens. Methods: siRNA targeting Tet1 was used to transiently knockdown the expression of Tet1 in chicken PGCs, and the genomic DNA methylation status was measured. The proliferation of chicken PGCs was detected by flow cytometry analysis and cell counting kit-8 assay when activation or inhibition of Wnt4/β-catenin signaling pathway. And the level of DNA methylation and hisotne methylation was also tested. Results: Results revealed that knockdown of Tet1 inhibited the proliferation of chicken PGCs and downregulated the mRNA expression of Cyclin D1 and cyclin-dependent kinase 6 (CDK6), as well as pluripotency-associated genes (Nanog, PouV, and Sox2). Flow cytometry analysis confirmed that the population of PGCs in Tet1 knockdown group displayed a significant decrease in the proportion of S and G2 phase cells, which meant that there were less PGCs entered the mitosis process than that of control. Furthermore, Tet1 knockdown delayed the entrance to G1/S phase and this inhibition was rescued by treated with BIO. Consistent with these findings, Wnt/β-catenin signaling was inactivated in Tet1 knockdown PGCs, leading to aberrant proliferation. Further analysis showed that the methylation of the whole genome increased significantly after Tet1 downregulation, while hydroxymethylation obviously declined. Meanwhile, the level of H3K27me3 was upregulated and H3K9me2 was downregulated in Tet1 knockdown PGCs, which was achieved by regulating Wnt/β-catenin signaling pathway. Conclusion: These results suggested that the self-renewal of chicken PGCs and the maintenance of their characteristics were regulated by Tet1 mediating DNA demethylation through the activation of Wnt4/β-catenin signaling pathway.