Determination of Sex Hormones in Antler Velvet by High Performance Liquid Chromatography Tandem Mass Spectrometry

Eighteen sex hormones in antler velvet were determined by high performance liquid chromatography tandem mass spectrometry.The solid phase extraction was applied to eliminating the matrix effect.The exp...     

Synthesis,Structure and Characterization of Three Metal Molybdate Hydrates: Fe(H2O)2(MoO4)2·H3O,NaCo2(MoO4)2(H3O2)and Mn2(MoO4)3·2H3O

Three metal molybdate hydrates,Fe(H2O)2(MoO4)2·H3O(FeMo),NaCo2(MoO4)2(H3O2)(CoMo)and Mn2(MoO4)3·2H3O(MnMo),were synthesized by the mixed-solvent-thermal methods and characterized by singlecrystal X-ray...     

Analysis of Peanut Oil Adulterated with Other Edible Oils by Spectrophotometry

Since peanut oil(PO) is more expensive than other seed oils, some PO is adulterated with other cheap seed oils, such as soybean oil, palm olein, cottonseed oil, corn oil and rapeseed oil. The conventional method for determining whether PO was adulterated is to detect the freezing point of oils. The proposed method for the determination of adulterants in PO was based on monitoring the change of absorbance when the sample was refrigerated. A special spectrophotometer was developed. A total of 10 kinds of POs from different suppliers were chosen and adulterated with other seed oils at the volume fraction levels ranging from 5% to 30%. A total of 150 samples were analyzed by the proposed method and the results were satisfactory.     

Antitumor Active Protein-containing Glycans from the Body of Ganoderma tsugae

To explore the effects of traditional herbal medicine Ganoderma tsugae(G. tsugae) on immunomodulatory and antitumor activities, the crude polysaccharides of G. tsugae were purified by filtration, diethylaminoethyl(DEAE) sepharose-fast flow chromatography and sephadex G-100 size-exclusion chromatography. Two main fractions, protein- containing glycans CSSLP-1 and CSSLP-2, were obtained via the gradient elution. The protein content, molecular weight, and monosaccharide composition of the two fractions were analyzed. Furthermore, the influence of the protein-containing glycans from G. tsugae on the activation of human acute monocytic leukemia cell line(THP-1) and their antitumor activities to the human hepatocellular liver carcinoma cell(HepG-2) in vitro were evaluated. The results indicate that CSSLP-1 and CSSLP-2 could increase the pinocytic activity of THP-1 cells and induce THP-1 cells to produce the cytokines of TNFα and IL-2, significantly. CSSLP-1 and CSSLP-2 also played an inhibiting effect on the cancer cell(HepG-2). Moreover, the anti-proliferation activity of CSSLP-1 and CSSLP-2 increased with the participation of TNFα and IL-2 or other antitumor factors induced from THP-1 cells by G. tsugae protein-containing glycan fractions.     

Synthesis of Pt/C Electrocatalysts Under Protection of Glucose and Their Improved Methanol Electrooxidation Activity

Carbon supported Pt(Pt/C) electrocatalysts were prepared with glucose as protection agent and NaBH₄ as reductant. The Pt nanoparticles deposited on carbon support presented reduced size and well dispersity attributed to the protection effect of glucose. Glucose absorbed on the particle surface was readily removed by water washing without leading to agglomeration of the Pt nanoparticles. The as-prepared Pt/C electrocatalysts showed improved mass activity for methanol electrooxidation compared to the catalyst prepared without glucose protection. The improved performance is attributed to the larger electrochemical active surface area thus increased active sites on the Pt/C elctrocatalysts prepared under the protection of glucose.     

Properties of DR1/PMMA-co-GMA for High Speed Electro-optical Switch

A non-linear optical(NLO) material was synthesized by means of a simple method. This material can be applied in electro-optical(EO) devices, such as EO switches and modulators. The Disperse Red 1(DR1) was doped in polymethyl-methacrylate-co-glycidyl methacrylate(PMMA-co-GMA) as the NLO active chromophore. The synthesis process and material structure were expressed. The thermal properties, surface morphology and optical characteristics of the material were investigated by means of differential scanning calorimetry(DSC), thermogravimetric analysis (TGA), atomic force microscopy(AFM), and m-lines technique. Using the reflection technique, the value of the electro-optical coefficient γ₃₃ was measured as 11 pm/V at a wavelength of 1310 nm. An EO switch with nanosecond response based on this material has been fabricated.     

Characterization of Nanostructures in Acellular Cementum of Human Tooth Roots

Determining the microstructure in human cementum might help us design new kinds of replacement materials for the treatment of teeth injury and disease. The authors characterized the nanostructures in the cementum of health human teeth via scanning electronic microscopy(SEM). It was found that the acellular cementum is mainly composed of two kinds of nanostructures―inorganic nanoparticles and organic nanofibers. And the inorganic nanoparticles show a tendency to arrange along the organic nanofibers. Based on the micro-molding in capillary strategy, the distribution of organic component in acellular cementum was copied with UV curable resin. After removing the inorganic nanoparticles by acid etching, many isolated spindle shape nanopores were left in polymer, which su- ggested that the inorganic nanoparticles should have been isolated by the organic component in cementum, and should be oval or nanosheet in shape. We hope the present work could provide reference for the biomimetic preparation of tissue engineering materials, and help us design new types of tooth implant.     

Evaluation of Stabilization Performances of Antioxidants in Poly(ether ether ketone)

Two types of antioxidants(a primary antioxidant and a secondary antioxidant) were used to improve the stability of poly(ether ether ketone)(PEEK). The effects of the antioxidants on the properties of PEEK and the stabilization mechanism were investigated by some characterization methods, such as rheometer, thermogravimetric ana- lysis(TGA), universal tester and electron spin resonance(ESR). The results indicate that the efficiency of the phosphorous antioxidant(DS) in improving the stability of PEEK was better than that of the phenolic antioxidant(DN) in both melting stability and thermal stability, and the thermal stability of PEEK sample containing 0.07%(mass fraction) DS was the best among all the samples due to the decrease of the free radicals density, as proven by ESR measurement. Additionally, no obvious changes could be observed in mechanical properties of PEEK containing antioxidants compared to those of virgin PEEK.     

Biostimulation-enhanced Biodegradation of Nitrobenzene in Contaminated Groundwater

In this study, biostimulation technology was used for bioremediation of nitrobenzene-contaminated groundwater by adding a mixture of lactose and phosphate, peptone, and beef extract. During the process of biostimulation, the remediation effectiveness, microbial dehydrogenase activities and microbial densities were investigated; the varieties of microbial community structure and composition were analyzed by polymerase chain reaction-denaturing gradient gel electrophoresis(PCR-DGGE) technique and the relative abundances of nitrobenzene-degrading gene(nbzA) were determined by fluorescence quantitative real-time PCR(RT-PCR). Findings show that the removal rate of nitrobenzene in groundwater could reach about 60% by biostimulation with lactose and phosphate, 70% with peptone and 68% with beef extract. The microbial dehydrogenase activities and microbial densities were all improved obviously via biostimulation. The results of PCR-DGGE show that the microbial diversities were improved, and more than ten kinds of dominant microorganisms were detected after biostimulation. RT-PCR results show that the relative abundances of nbzA gene of microbes in groundwater were increased significantly, which indicated that biostimulation actually enhanced the growth of nitrobenzene-degrading bacteria. Therefore, biostimulation is a cost-effective and feasible bioremediation technique for nitrobenzene-contaminated groundwater.     

Simultaneous Forecast for Three Speciations of Heavy Metal Elements Using Fuzzy Cluster-Artificial Neural Network

The three speciations(water extract, adsorption and organic speciations) of Cu, Zn, Fe and Mn in geo-chemical samples were determined by fuzzy cluster-artificial neural network(FC-ANN) method coupled with atomic absorption spectrometry. A back-propagation artificial neural network with one input node and three export nodes was constructed, which could forecaste three speciations of heavy metals simultaneously. In the learning sample set, the three speciations of each element were allowed to change in a wide concentration range and the accuracy of the analysis was apparently increased via the learning sample set optimized with the help of the fuzzy cluster analysis. The average relative errors of the three speciations of Cu, Zn, Fe or Mn from 100 geo-chemical samples were less than 5%. The relative standard deviations of the three speciations of each of four heavy metals were 0.008%―4.43%.