Advanced Materials Research Vols. 343-344

Abstract: .Aiming at the high salinity at low-permeability reservoirs, a strain named S-4 that can yield a kind of bio-surfactants was screened from the produced water of oil wells in use of the Hemolysis of the bio-surfactants and its characteristics of making the color of blue gel plate change in its formation process. The laboratory results show that the surface tension of the strains fermentation liquor becomes less than 30mN/m after cultured by crude oil as the carbon source, and it would remain at the value of 31mN/m even if the concentration becomes a half; this bio-surfactant keeps stable when the salinity is in the range of 4000mg/L～50000mg/L; In physical experiments the strains can improve crude oil recovery ratio by 4% which shows a good oil displacement effect.

Abstract: High performance liquid chromatography was employed to determine the contents of eight marker bioactive components such as rhein, aloe-emodin, nobiletin, emodin, honokiol, magnolol, chrysophanol, and physcion in the traditional Chinese medicinal preparation, Xiaochengqi decoction. The separation was performed on a C₁₈ column by stepwise gradient elution with water (1.1% v/v acetic acid)–acetonitrile (0.01min, 75:25; 15 min, 60:40; 30 min, 50:50; 40 min, 45:55; 55min, 30:70) as the mobile phase at a flow-rate of 1.0ml·min^-1, with UV detection at 254nm. Eight regression equations showed good linear relationships between the peak area and the amount of each marker. The recoveries of the markers were 99.6, 99.5, 97.4, 97.7, 98.9, 97.9, 99.0 and 98.5%, respectively. The repeatability and reproducibility (relative standard deviation) of the method were less than 2.1% and 2.5%, respectively.

Abstract: A simple method for the determination of imidaclothiz residue in soil and citrus samples was established by ultra-performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS) under the multiple reaction monitoring (MRM) mode. Imidaclothiz was extracted from soil and citrus samples using a procedure known as the quick, easy, cheap, effective, rugged, and safe (QuEChERS) method. Experiments on 3 fortification concentrations were carried out, and the limit of determination is 1.0×10^-10 g. The recoveries ranging from 80.7% to 118.9% with high correlation coefficient (r>0.99) were obtained within the linear range (0.01-1.0mg/kg). Based on the above method, we also carried out field trials. Results showed that the degradation of imidaclothiz coincided with the fitted equations Ct=0.1028e^-0.0266t, Ct=0.1778e^-0.0311t in soil and Ct=1.3612e^-0.0632t, Ct=0.7162e^-0.0968t in citrus, respectively, with the average half-lives of 24.2 d in soil and 9.1 d in citrus, respectively. The results indicate that the developed method is fast, accurate, and easy to operate. It also demonstrates that the method can meet the requirements of determination of imidaclothiz in soil and citrus.

Abstract: The L-ascorbic acid can reduce the nitrite to nitric oxide, but the elevated nitrite-to-L-ascorbic acid ratio predisposes to the formation of potentially carcinogenic N-nitroso compound. We study the chemicals which nitrite reacted to L-ascorbic acid with an elevated L-ascorbic acid-to- nitrite ratio in the solution. The products, when the nitrite reacted with L-ascorbic in the solution, were nitric oxide (NO), dinitrogen monoxide (N₂O) and nitrogen gas (N₂). We give advice that it maybe useful to understand the products which nitrite reacts with L-ascorbic acid in the human beings and other organisms.

Abstract: A pseudorabies virus (PRV) mutant with deletions in genes for glycoprotein I (gI) and glycoprotein E (gE) was constructed and evaluated as a candidate vaccine strain for its protective by virulent wildtype (wt) PRV Ea strain challenge in pigs. Transfer plasmid pIESE was constructed and co-transfected with PRV genome into IBRS-2 cells to generate a recombinant mutant PRV Ea gI^-/gE^- virus. The recombinant virus was confirmed by Southern blotting and indirect immunofluorescence assay (IFA). In animal experiments, the immunogenicity was tested by PRV-enzyme-linked immunosorbent assay (ELISA) and PRV neutralizing assay. PRV Ea gI^-/gE^- elicited significant humoral immune responses to wt PRV Ea, and PRV gI^-/gE^- immunization protected pigs against a lethal challenge by virulent PRV Ea strain. These results suggested that the recombinant PRV Ea gI^-/gE^- might be considered as a potential candidate vaccine against PRV.

Abstract: This work is to examine ways to chemically modify soy proteins flours and analyze the results and determine the adhesive performance. Reaction with acetic anhydride converts amine and hydroxyl groups to amides and esters, respectively that are less polar and can make the adhesive more water resistant.The succinic anhydride reacts with these same groups but the products have terminal carboxylic acid groups that can react with the polyamidoamine-epichlorohydrin (PAE) resin that is used to cross-link the soy adhesives for improving bond strength. The attenuated total reflectance infrared spectroscopy (ATR-IR) is used to examine changes in the soy flour in going from unmodified to acetylated and succinylated state.

Abstract: Silk fibroin (SF) and β-tricalcium phosphate (β-TCP) had been used in biomedical applications for these years. The potential of silk and β-TCP for application in tissue engineering is currently being explored. The purpose of this study was to prepare and characterize a 3D scaffold consisting of nano-β-TCP/SF composite. XRD and FT-IR analysis showed that predominant crystalline phase of calcium phosphate was β-TCP; a chelate effect between SF and Ca²⁺ was happened at complexing period of SF and β-TCP. The compressive strength of nano-β-TCP/SF composite was 42 MPa ± 0.12 MPa. In vitro cell cultivation experiment showed that the composite was a good matrix for the growth of osteoblasts. Conclusion: the incorporation of SF into nano-β-TCP can enhance both mechanical strength and bioactivity of the scaffold, which suggests that the β-TCP/SF composite may be a potential biomaterial for tissue engineering.

Abstract: The bio-toxicity of Fe⁰ nanoparticles on the denitrifying bacterial- Alcaligenes eutrophus was detected by the two methods of detecting inhibition of the growth of microorganisms and nitrification inhibition rate. The results showed that Fe⁰ nanoparticles had obvious toxicity on the growth and nitrification inhibition rate. Besides, there had distinct relationship between dose and toxicity of Fe⁰ nanoparticles. Meanwhile, we also studied effects of different kinds of Fe⁰ nanoparticles on microorganism, including bimetallic nanoparticles(nano Fe–Ni) and coated iron nanoparticles (sodium oleate–Fe⁰nanoparticles). We detected that the bio-toxicity of these three Fe⁰ nanoparticles followed the sequence of Ni-containing nanoparticles>unmodified NZVI>the sodium oleate–Fe⁰ nanoparticles. In conclusion, Fe⁰ nanoparticles had visible toxicity on the denitrifying bacterial, but we can decrease the toxicity of Fe nanoparticles by surface coating and decoration of nano-metal materials.

Abstract: How to choose instrument appropriately, especially in the process of fracture internal fixation healing, is always a Gordian knot. Although the resistive action between the bone tissue and SMA (shape memory alloy) internal fixation material is not totally visible, the resistance has a very important influence on the healing of the bone tissue. Based on the phenomena above and the consequences arise from the treatment in the use of the clutching internal fixator, an experiment platform is designed in this article which can make an intensive study of the mechanics properties of the clutching internal fixator, in order to find out the embracing force of clutching internal fixator in the clinical cure. This platform can accurately grasp the distribution of the embracing force when the clutching is under the working condition, and it provides more scientific evidence for the clutching internal fixator which uses in clinical application.

Abstract: The pollution level of trace elements from nine types of fishes was study by ICP-AES techniques, and compare the pollution level differences of trace elements between fishes of fresh and marine waters. Assess the pollution risk of trace elements accumulated in fish tissues with the aquatic eco- environment from fresh and marine waters. The concentration changes of trace elements in fish tissues have some differences from freshwater fish tissues and marine water fish tissues, but the concentration distribution tendency of trace elements was similar. Mg elements had high concentration, Fe elements were rich in fish tissues, and Zn elements were in a relatively lower level in fish tissues. Their bioaccumulation levels with other trace elements, such as Mn, Cu, Ni, Co, Se, Cr, Mo, Sn and Al, were not considered as main contaminate elements in fish tissues, the pollution level of toxic elements like Cd, Pb and Hg in most fish tissues from this study demonstrated that the cultivation aquatic eco- environments of fresh water and marine water were relatively safe. But the potential pollutions of toxic elements in fish tissues, such as Cd, Pb, As and Hg should pay main attention.