Showing papers by "Henan University of Technology published in 2010"

Recycling utilization patterns of coal mining waste in China

Abstract: With the fast development of Chinese economy in recent years, China has become the largest coal production and consumption country in the world. Correspondingly, it has produced large quantities of mining waste including coal gangue, coal sludge, fly-ash, coal mine drainage and coal-bed methane (CBM) that are hazardous to the soil, air, and water. Based on the theory and practice of sustainable development and recycling economy, the paper will discuss and analyze the mining waste management in Jincheng Anthracite Mining Group, Shanxi Province, where they have found the paths to realize the mining waste reusing and recycling in colliery. They had established many green industrial chains in the mining waste treatment: the gangue piles turned into man-made eco-park, gangue used for power generation, fly-ash used in the building material, the coal mining water reused and recycled in closed pipelines, the CBM extracted for home-burning and electricity generation, etc. The coal mining waste has been converted into wealth and played more and more important roles in many fields. The practice indicated that these patterns can be applied in other coal mines.

Computational approaches for microRNA studies: a review.

Abstract: MicroRNAs (miRNAs) are one class of tiny, endogenous RNAs that can regulate messenger RNA (mRNA) expression by targeting homologous sequences in mRNAs. Their aberrant expressions have been observed in many cancers and several miRNAs have been convincingly shown to play important roles in carcinogenesis. Since the discovery of this small regulator, computational methods have been indispensable tools in miRNA gene finding and functional studies. In this review we first briefly outline the biological findings of miRNA genes, such as genomic feature, biogenesis, gene structure, and functional mechanism. We then discuss in detail the three main aspects of miRNA computational studies: miRNA gene finding, miRNA target prediction, and regulation of miRNA genes. Finally, we provide perspectives on some emerging issues, including combinatorial regulation by miRNAs and functional binding sites beyond the 3′-untranslated region (3′UTR) of target mRNAs. Available online resources for miRNA computational studies are also provided.

Enzymatic transesterification of soybean oil by using immobilized lipase on magnetic nano-particles

Abstract: Lipase was covalently immobilized onto magnetic Fe3O4 nano-particles by using 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide (EDAC) as an activating agent, and the bound lipase was used to catalyze the transesterification of vegetable oils with methanol to produce fatty acid methyl esters. The binding of lipase to magnetic particles was confirmed by enzyme assays, transmission electron microscopy (TEM) and Fourier transform infrared (FT-IR) spectra. It was determined that the immobilized lipase exhibited better resistance to temperature and pH inactivation in comparison to free lipase. Using the immobilized lipase, the major parameters affecting the transesterification reaction, such as the alcohol/oil molar ratio, enzyme loading and free fatty acid present in reactants were investigated to obtain the optimum reaction condition. The conversion of soybean oil to methyl esters reached over 90% in the three-step transesterification when 40% immobilized lipase was used. Moreover, the lipase catalyst could be used for 3 times without significant decrease of the activity.

Effects of fermentation by lactic acid bacteria on the antigenicity of bovine whey proteins

Abstract: BACKGROUND: The main whey proteins α-lactalbumin (α-LA) and β-lactoglobulin (β-LG) are considered as the major allergens in cow's milk. Microbial fermentation can produce some proteolytic enzymes, which can induce the degradation of milk protein allergens. In this study, the effects of fermentation by lactic acid bacteria on the antigenicity of α-LA and β-LG were investigated using indirect competitive ELISA. Meanwhile, the proteolysis of milk proteins was detected by TNBS assay and SDS-PAGE electrophoresis. RESULTS: Fermentation by lactic acid bacteria could significantly reduce the antigenicity of α-LA and β-LG in skim milk. Combined strains of Lactobacillus helveticus and Streptococcus thermophilus were the most effective in reducing the antigenicity of both whey proteins. In addition, α-LA and β-LG antigenicity decreased to a lower value at 6 h of fermentation and at 0.5 d of cold storage by fermentation with the combined strains. The results of TNBS assay and SDS-PAGE electrophoresis showed that lactic acid bacteria strains used in this study hydrolysed whey proteins only to a limited extent. CONCLUSION: The fermentation with lactic acid bacteria is an effective way to reduce whey proteins antigenicity. Copyright © 2010 Society of Chemical Industry

Changes in firmness, pectin content and nanostructure of two crisp peach cultivars after storage

Abstract: To investigate the fundamental of firmness changes of crisp peaches, firmness and pectin contents of two peach (Prunus persica L. Batsch) cultivars (‘Cangfangzaosheng’ and ‘Songsenzaosheng’) stored at 2 °C, 8 °C and 15 °C were investigated. Sodium carbonate-soluble pectin (SSP) extracted showed the highest correlation (positive) with firmness among the three kinds of pectins (water-soluble pectin, chelate-soluble pectin and SSP). The qualitative and quantitative information about SSP nanostructures were determined by atomic force microscopy (AFM). The widths of the peach SSPs were very consistent. The SSP chain widths of both peach cultivars were similar and were composed of several basic units. Schematic models of the changes of the chain widths were proposed. The results indicate that the firmness of peach was closely related with the contents and nanostructural characteristics of SSP, which might be hydrolyzed by enzymes in fruit flesh.

Chemical Characteristics and Fatty Acid Profile of Foxtail Millet Bran Oil

Abstract: Chemical characteristics of a sample of foxtail millet bran and its oil, focusing on the approximate composition of foxtail millet bran and the fatty acid profile, physicochemical properties and tocopherol composition of foxtail millet bran oil, are presented in this work. The results indicate that the millet bran constituted 9.39 ± 0.17% crude oil, 12.48 ± 0.41% crude protein, and 51.69 ± 2.14% crude fiber. The specific gravity, refractive index, saponification value, and unsaponifiable matter content of millet bran oil were 0.9185 ± 0.0003 g/cm3\( \left( {d_{20}^{20} } \right) \), 1.4676 ± 0.0002 \( \left( {n_{D}^{40} } \right) \), 186.29 ± 0.51 mg KOH/g, and 3.62 ± 0.19 g/100 g, respectively. The tocopherol content was 64.83 ± 0.83 mg/100 g oil, which consisted mainly of γ-tocopherol (48.79 ± 0.46 mg/100 g oil) and α-tocopherol (15.53 ± 0.31 mg/100 g oil). The millet bran oil was rich in linoleic acid (66.5%) and oleic acid (13.0%). The saturated fatty acids included palmitic acid (6.4%) and stearic acid (6.3%). The major fatty acid in the sn-2 position of the millet oil was linoleic acid (71.2%). The dominant triacylglycerols, calculated according to the 1,3-random-2-random hypothesis, were trilinoleate (LLL, 29.3%) and dilinoleoyl-monoolein (LLO, 17.2%). This work might be useful for developing applications for millet bran and its oil.

Fundamental-solution-based finite element model for plane orthotropic elastic bodies

Abstract: A new hybrid finite element formulation is presented for solving two-dimensional orthotropic elasticity problems. A linear combination of fundamental solutions is used to approximate the intra-element displacement fields and conventional shape functions are employed to construct elementary boundary fields, which are independent of the intra-element fields. To establish a linkage between the two independent fields and produce the final displacement-force equations, a hybrid variational functional containing integrals along the elemental boundary only is developed. Results are presented for four numerical examples including a cantilever plate, a square plate under uniform tension, a plate with a circular hole, and a plate with a central crack, respectively, and are assessed by comparing them with solutions from ABAQUS and other available results.

Preparation and physicochemical properties of the complex of naringenin with hydroxypropyl-beta-cyclodextrin.

Abstract: In this study a complex of naringenin with hydroxypropyl-beta-cyclodextrin (HP-beta-CD) was prepared to improve the hydrophilicity of naringenin. The physicochemical properties of the complex were analyzed by ultraviolet-visible spectrometry (UV), infrared spectrometry (IR), X-ray diffractometry (XRD), differential scanning calorimetry (DSC). The result showed that naringenin had been molecularly dispersed in the HP-beta-CD matrix, not forming a new compound and HPLC analysis showed that the solubility of naringenin in water was enhanced from 4.38 microg/mL to 1,272.31 microg/mL.

Synthesis of starch esters in ionic liquids

Abstract: Chemical modification of corn starches with succinic anhydride or acetic anhydride was carried out using 1-butyl-3-methylimidazolium chloride (BMIMCl) as a reaction medium. The reaction progress was followed in terms of the degree of substitution (DS) for the starch derivatives. The results showed that the homogeneous esterification of starch at 5 : 1 molar ratio of anhydride/anhydroglucose units at 100°C led to formation of acetates with DS ranging from 0.37 to 2.35 and succinates with DS ranging from 0.03 to 0.93. Moreover, the reaction media applied could be easily recycled and reused. Further, the formation of starch esters was confirmed by the presence of the carbonyl signal in the FTIR and NMR spectra. It was shown that the starch granules were mostly converted from their crystalline structure into amorphous state in the ionic liquid system under the given reaction conditions. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010

Enzymatic epoxidation of soybean oil methyl esters in the presence of free fatty acids

Abstract: Epoxides of soybean oil methyl esters (SMEs) are biodegradable, non-toxic, and renewable epoxy plasticizers. The objective of the present work was to investigate the effects of free fatty acids on the enzymatic epoxidation of SMEs. The results showed that the epoxidation of SMEs depended on the type of the added free fatty acid. For saturated (

Fast repair of DNA radicals

Abstract: This tutorial review highlights the mechanism of a novel non-enzymatic fast repair of DNA damage, which refers exclusively to repair DNA radicals including DNA-OH* adducts, DNA radical cations and anions by various endogenous, natural and synthetic compounds. The repair rate constants are as high as 10(9) M(-1) s(-1). In cells, when the enzymatic repair system was inhibited or before the enzymatic repair mechanism was initiated, DNA oxidative damage was significantly reduced by natural polyphenols. This decrease of DNA damage is assigned to the fast repair. Fast repair takes place through an electron transfer process, and docking of polyphenol into the DNA minor groove could be the essential step.

Mutagenesis induced by high hydrostatic pressure treatment: a useful method to improve the bacterial cellulose yield of a Gluconoacetobacter xylinus strain

Abstract: Bacterial cellulose (BC) is a new biomaterial which has wide application potential in various industries. BC industrialization requires bacterial strains with high BC productivity. The objective of this study is to increase the BC yield of a Gluconoacetobacter xylinus strain through mutagenesis induced by high hydrostatic pressure (HHP) treatment. In this study, the parental strain in its exponential phase was treated at 250 MPa and 25 °C for 15 min to induce mutagenesis using a HHP machine. The HHP-treated strains were incubated in glucose agar plate at 30 °C for 4 days. After the incubation, 50 larger colonies in these plates were randomly selected and cultivated to produce BC membrane in a tailor-made glass vessel, and wet weights of the BC membranes were tested. Compared with the parental strain, 29 mutants showed higher BC yields, of which eight mutants with BC yield >130.00 g/L were initially screened and were then cultivated for five generations to test their genetic stabilities for BC production. Among the eight mutants, M438, a mutant which showed the highest average BC yield (158.56 g/L) and lowest coefficient of variation (2.4%) for five generations, was finally screened as objective mutant. HHP treatment can serve as an effective method to cause mutagenesis in BC-producing bacteria. The HHP-treated strains with significantly higher BC yield than parental strain can be screened from the HHP-induced mutants.

Source term identification for an axisymmetric inverse heat conduction problem

Abstract: We consider an inverse heat source problem of determining the heat source term from the final temperature history of a cylinder. This problem is ill-posed. A simplified Tikhonov regularization method is applied to formulate regularized solution, which is stably convergent to the exact one with a logarithmic type error estimate.