3,134 publications from this institution
Caught in a trap: Colloids of gold nanoparticles coated with a thermally responsive poly-(N-isopropylacrylamide) (pNIPAM) microgel can trap molecules in different ways as a function of temperature (see scheme). The porous pNIPAM shells prevent electromagnetic coupling between metal particles, thus providing highly reproducible surface-enhanced Raman scattering (SERS) signals and intensity. Detailed facts of importance to specialist readers are published as "Supporting Information". Such documents are peer-reviewed, but not copy-edited or typeset. They are made available as submitted by the authors. Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article.
This paper proposed a novel HIL simulation platform which can supply a reliable locomotive model for adhesion control. Motor torque and currents can be shown in the model of traction motor. And writing the adhesion control algorithm to DSP makes it easier to test the algorithm in real locomotive.
Honeybee products have positive effects on the reproductive performance of mammals. Many honeybee product constituents are biologically active, with antioxidant, antimicrobial, antiviral, anti-inflammatory, immunomodulatory, antifungal, wound-healing, and cardio-protective properties. Honeybee products also improve male and female fertility rates by enhancing gamete cryopreservation, in vitro maturation and fertilization, and embryo development. Previously published studies confirmed their efficacy for alleviating reproductive toxicity caused by contaminants and lifestyle habits that impair overall health and well-being. However, high-dose oral administration of honeybee products may adversely affect the reproductive system, and unfavorable effects were alleviated by treatment cessation. For this reason, this review proposes that bioactive components from bee products can be used as a strategy for improving the reproductive performance and health of mammals.
Abstract The chemical structure of an aliphatic epoxy resin was studied by using gel permeation chromatography (GPC), Fourier transform infrared (FTIR), FTIR‐TGA (thermogravimetric analysis), mass spectrometry in fast atom bombardment (FAB) mode, and wet analysis. We found that when trimethylolpropane is used as starting monomer, only two OH groups are epoxidized. The resin and its different fractions have a functionality of two. Under the conditions of synthesis used by the supplier, three main products were found with masses of 246,339, and 430. No trifunctional product was detected. © 1995 John Wiley & Sons, Inc.
Abstract Ultrasound energy by means of a probe sonicator was used for leaching metal ions from plant tissue as a possible alternative to conventional digestion methods. The extraction conditions (composition of the extractant agent, sonication power and time and extraction steps) were optimised for copper, lead, manganese and zinc in an aquatic plant with certified metal contents (BCR N° 60 Lagarosiphon major). Metal determination in the extracts was carried out by Flame Atomic Absorption Spectrometry. Quantitative recoveries performing two extractions (ranging from 97.6% to 100%) were obtained for all the studied elements except for copper (74.18%). A good precision was also obtained, given that RSD were always lower than 2.5%. Key Words: Metal leachingaquatic plantflame atomic absorption spectrometrycopperleadmanganesezinc
Abstract A rapid and accurate HPLC‐DAD method was developed and validated to simultaneously determine eight B‐vitamins (VBs, namely thiamine, riboflavin, niacinamide, calcium pantothenic, pyridoxine, biotin, folic acid and cyanocobalamin) and phenolsulfonphthalein in rat intestinal perfusate. Chromatographic separation was achieved using an Inertsil ODS‐3 column (250 × 4.6 mm i.d., 5 μm) at a temperature of 40°C. Gradient elution mode was applied at the flow rate of 1.0 mL/min with the mobile phase of acetonitrile–30 m m K 2 HPO 4 (pH 5.80). The method was successfully applied to identify the effects of osmotic pressures on the absorption of the VBs. The absorption profiles of single and mixed VBs were also compared. Histological section technology was applied to observe the microstructure of small bowel mucosa after perfusion. The results indicated that each compound possessed a better absorption profile under isotonic conditions than under hypotonic or hypertonic conditions for single or mixed solutions. Compared with single VBs, better absorptions in mixed VBs were observed. Pathological tissue slice test suggested that hypotonic and hypertonic solutions changed or damaged the microstructure of mucosa to varying degrees. Taken together, the investigations indicated that multi‐VBs administered orally under isotonic condition could generate fast and complete absorption profiles for VBs.
Natural pyrazines, mainly methyl- or ethyl-substituted forms, are commonly applied as flavor ingredients in raw and roasted food. Meanwhile alkylpyrazines are used as food preservatives due to their effective antimicrobial action. These natural pyrazines are widely distributed in several biological systems such as plants, animals, and insects; each with respective physiological role. Besides, pyrazines are formed in food via thermal treatment and fermentation. This review presents the most comprehensive overview of pyrazines with correlation to their chemical structures and different applications with emphasis on their food applications. The major part deals with pyrazines generated in thermally treated food, reaction mechanisms highlighting factors and optimum conditions affecting their production. Additionally, the several metabolic reactions mediating for pyrazines metabolism in humans and excretion via the kidney are discussed and on context to their effects. Lastly, a review of the different techniques applied for pyrazines isolation, detection and quantitation is presented. The study provides future considerations and direction of research on this important dietary component and their applications. Pyrazines multifunctional chemistry is of value to the food sector, by presenting the best practices for their production whilst the detrimental effects are minimized.
