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An attempt has been made to reveal the effect of amphoteric poly(2-acryloyloxyethyl trimethyl ammonium chloride- co -acrylic acid) [P(ATAC- co -AA)] branches grafted onto the backbones of starch upon the adhesion-to-cotton, film properties, and desizability of maize starch for cotton warp sizing. Starch- g -poly[(2-acryloyloxyethyl trimethyl ammonium chloride)- co -(acrylic acid) [S- g -P(ATAC- co -AA)] was prepared by the graft copolymerization of 2-acryloyloxyethyl trimethyl ammonium chloride (ATAC) and acrylic acid (AA) with acid-converted starch (ACS) in aqueous medium using Fe 2+ –H 2 O 2 initiator. The adhesion was evaluated in term of bonding strength according to the FZ/T 15001-2008 whereas the film properties considered included tensile strength, work and percentage elongation at break. The evaluation was undertaken through the comparison of S- g -P(ATAC- co -AA) with ACS, starch- g -poly(acrylic acid), and starch- g -poly(2-acryloyloxyethyl trimethyl ammonium chloride). It was found that the amphoteric branch was able to significantly improve the adhesion and mitigate the brittleness of starch film. Zeta potential of cooked S- g -P(ATAC- co -AA) paste, depending on the mole ratio of ATAC to AA units on P(ATAC- co -AA) branches, had substantial effect on the adhesion and desizability. Increasing the mole ratio raised the potential, which favored the adhesion but disfavored the removal of S- g -P(ATAC- co -AA) from sized cotton warps. Electroneutral S- g -P(ATAC- co -AA) was superior to negatively grafted starch in adhesion and to positively grafted starch in desizability. Generally, it showed better sizing property than ACS, starch- g -poly(acrylic acid), and starch- g -poly(2-acryloyloxyethyl trimethyl ammonium chloride), and had potential in the application of cotton warp sizing. [ABSTRACT FROM AUTHOR]

Starch-g-poly(2-methacryloyloxyethyl trimethyl ammonium chloride-co-acrylic acid) (starch-g-P(DMC/AA)) with different zeta potentials was prepared via the graft copolymerization of acid-thinned cornstarch (ATS) with 2-methacryloyloxyethyl trimethyl ammonium chloride (DMC) and acrylic acid (AA) in aqueous medium using Fe2+–H2O2initiator. The investigation was carried out to reveal the influence of amphoteric branches grafted onto starch chains upon the adhesion of starch to textile fibers. Zeta potential of starch-g-P(DMC/AA) was adjusted by altering the mole ratio of DMC to AA charged into the copolymerization system. The adhesion was evaluated in terms of bonding strength and specific bonding strength of slightly sized roving based on a legal method (FZ/T 15001-2008) through the comparison of the amphoteric branch-grafted starch with ATS, starch-g-PAA, and starch-g-PDMC for warp sizing. It was found that the charged branches grafted onto starch chains were able to significantly enhance the adhesion. Zeta potential, depending on the mole ratio of DMC to AA units in the grafting branches, showed evident effect on the adhesion and desizability of the grafted starch. Increase in the potential favored to improve the adhesion, but disfavored the removal of the starch from sized warps. Alkali-oxidant agent desizing test confirmed that the starch-g-P(DMC/AA) with neutral potential was desizable. The amphoteric branch-grafted starch exhibited potential application as size base materials in warp sizing operation if its zeta potential was neutral. [ABSTRACT FROM AUTHOR]

A mesoporous silica-supported Ni–Co composite metal oxide has been synthesized and applied as an effective heterogeneous catalyst for the selective catalytic oxidation of benzyl alcohols. Various characterization methods were employed to confirm the successful synthesis of the catalysts and their nanostructure. The catalytic performances of these catalysts in the selective oxidation of substituted benzyl alcohols to aromatic aldehydes were systematically investigated using molecular oxygen from the air as the oxidant under atmospheric pressure. The NiCo@SBA-15 catalyst exhibited remarkable performance, achieving nearly 98 % conversion and almost complete selectivity at a temperature of 120 °C for 10 h, operating at 1 atm of air pressure. This catalytic performance can be attributed to the synergistic effect between Ni and Co ions, resulting in the generation of new surface-active sites in the catalyst. The catalyst also demonstrated favorable applicability and universality. Moreover, A plausible catalytic mechanism has been proposed involving the synergistic effect between bimetal species and oxygen vacancy. Mesoporous silica-supported Ni–Co composite metal oxide acted as efficient heterogeneous catalyst for the selective catalytic oxidation of benzyl alcohols. [Display omitted] • NiCo@SBA-15 catalysts has been prepared for the selective catalytic oxidation of benzyl alcohols. • The reaction utilized molecular oxygen from the air as the oxidant under atmospheric pressure. • The catalytic performance is strongly dependent on the synergistic effect between Ni and Co ions. [ABSTRACT FROM AUTHOR]

Background: Accumulated studies reported abnormal gene expression profiles of hepatocellular carcinoma (HCC) by cDNA microarray. We tried to merge cDNA microarray data from different studies to search for stably changed genes, and to find out better diagnostic and prognostic markers for HCC.Methods: A systematic review was performed by searching publications indexed in Pubmed from March 1, 2001 to July 1, 2016. Studies that reporting cDNA microarray profiles in HCC, containing both tumor and nontumor data and published in English-language were retrieved. The differentially expressed genes from eligible studies were summarized and ranked according to the frequency. High frequency genes were subjected to survival analyses. The expression and prognostic value of alanine-glyoxylate and serine-pyruvate aminotransferase (AGXT) was further evaluated in HCC datasets in Oncomine and an independent HCC tissue array cohort. The role of AGXT in HCC progression was evaluated by proliferation and migration assays in a human HCC cell line.Results: A total of 43 eligible studies that containing 1917 HCC patients were included, a list of 2022 non redundant abnormally expressed genes in HCC were extracted. The frequencies of reported genes were ranked. We finally obtained a list of only five genes (AGXT; ALDOB; CYP2E1; IGFBP3; TOP2A) that were differentially expressed in tumor and nontumor tissues across studies and were significantly correlated to HCC prognosis. Only AGXT had not been reported in HCC. Reduced expression of AGXT reflected poor differentiation of HCC and predicts poor survival. Knocking down of AGXT enhanced cell proliferation and migration of HCC cell line.Conclusions: The present study supported the feasibility and necessity of systematic review on discovering new and reliable biomarkers for HCC. We also identified a list of high frequency prognostic genes and emphasized a critical role of AGXT deletion during HCC progression. [ABSTRACT FROM AUTHOR]

High strength steel (HSS) with excellent strength, superior toughness, and good weldability is widely utilized in engineering. However, the corresponding design provisions for HSS columns (i.e. 960 MPa and 800 MPa) have not been provided in existing specifications. Mode interaction, sensitive to imperfections, has profound effect on the buckling behavior of columns. To investigate the interactive buckling behavior of 800 MPa HSS welded T-section members, the experiment of 13 welded T-section columns under axial compression is conducted. Parametric analysis is performed to study the influence of the width-to-thickness ratio of plates and the slenderness ratio of column on the buckling behavior of HSS member under axial compression using finite element (FE) analysis. It is found that the torsional angle increases as the height-to-thickness ratio of web increases and the local out-of-plane deformation is more serious for the specimen with large width-to-thickness ratio of plates. Various design formulae for the ultimate load of 800 MPa HSS welded T-section column are evaluated by experimental results in this study. GB50017-2017 and Eurocode 3 slightly underestimates the ultimate load and AISC 360-16 is a little overestimated in predicting the ultimate load. More accurate empirical formulae modified from Eurocode 3 are developed. Reliability analysis is performed to evaluate various models of the ultimate load. • Torsion appears earlier than out-of-plane bending in columns with thick plates. • Out-of-plane bending develops earlier than torsion in columns with thin plates. • GB50017-2017 and Eurocode 3 are slightly conservative for the ultimate load. • ANSI/AISC 360-16 is a little overestimated for the ultimate load. • More accurate model for the ultimate load of columns is developed. [ABSTRACT FROM AUTHOR]

The precise estimation of position is an essential concern for the control of a switched reluctance motor (SRM). Given the prominent role of position, the promising sensorless control approach for an SRM drive should be capable of providing accurate position. An inductance-based approach has been widely applied in the position estimation. However, the estimated accuracy suffers from the magnetic saturation effect, resulting in the poor performance of sensorless operation. This paper presents a reversible synchronization of commutation with the corresponding rotor position for SRM. With the consideration of magnetic saturation, the proposed approach is taken as a suitable candidate and plays an essential role in accommodating the requirement of optimal control. The relationship between a typical inductance position and magnetic circuit saturation is investigated. The instant of the intersections is sensed by comparing the instantaneous inductance of adjacent phases. Thus, the predicted position is obtained with the information of the special point and the calculated average speed. Compared with other existing methods, the proposed approach has the certain advantages, such as the ability to update the estimated speed and position six times per electrical period, which guarantees the estimated accuracy. The proposed approach is also valid even when the motor is operated at an acceleration state and heavy load operation. In addition, the requirement of the educated inductance structure is not unnecessary, less memory space is needed in the chip, and the accumulated error is eliminated. The simulation and experimental findings demonstrate the feasibility and practicality of the proposed position estimation approach with carrying out the inertial operation, load mutation, and high-speed test. [ABSTRACT FROM AUTHOR]

The high current ripple and torque ripple are the main drawbacks of the switched reluctance motor (SRM) since the nonlinearity and double saliency, which limits its applications. In order to eliminate the current variation and torque ripple, an optimized pulse width modulation (PWM) control is presented in this paper. The voltage ratio duty is able to be predicted precisely according to the information of the motor running parameter. Based on torque sharing functions (TSFs), the current profile is pre-computed and four regions are defined according to the reference current profiles. The three modes, excitation, demagnetization and freewheeling, are flexibly chosen according to the characteristic of the current profile. It is indicated that it is better than that of conventional PWM modulation in terms of current ripple and the current tracing performance is improved without increasing the switching frequency or changing the hysteresis band. The current ripple is defined as the peak-to-peak value dividing the average value and it is reduced by 40%. A comparison in terms of the torque ripple and copper loss is also carried out: the torque ripple is significantly reduced via the proposed scheme under both magnetic linear and saturation conditions. The torque ripple and copper loss are reduced by about 70% and 12%, respectively. The validity and effectiveness of the proposed control strategy is verified by simulation and experimental results. [ABSTRACT FROM AUTHOR]