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Wang S.,Shanghai University | Fu P.,Shanghai University | Liu L.,Shanghai University | Wang L.,National Engineering Research Center | And 4 more authors.
RSC Advances | Year: 2016

An integrative strategy using LC-Q/TOF-MS and LC-QqQ-MS/MS coupled with multi-variate statistical analysis of principal component analysis (PCA) and orthogonal partial least squares discriminant analysis (OPLS-DA) was developed to screen and identify the constituents transported into the rat cerebrospinal fluid (CSF) after oral administration of Jitai tablets (JTTs). CSF samples were pretreated with cold methanol prior to liquid chromatography, and the separation was carried out on a HSS T3 column with a linear gradient elution. Mass spectra were acquired in positive ion mode for analyte identification and targeted MS/MS mode for quantification. In the S-plot of OPLS-DA, twenty-six interested ions were extracted, among which, sixteen absorbed prototype components of JTT and seven metabolites were identified in vivo. Cysteine conjugation, demethylation and glucuronidation were the major metabolic reaction types of the identified constituents. An LC-MS/MS method with targeted multiple-reaction monitoring of scopolamine, tetrahydrocoptisine, tetrahydroberineper, protopine, tetrahydropulmatine and corydaline in rat CSF was developed to validate the identification results. The concentration of the six compounds in rat CSF was in the range of 0.014-1.678 ng mL-1. In conclusion, a LC-MS based metabolomics approach can provide a rapid and sensitive method for characterizing bioactive components of JTT at micro concentration on pathological biopsy, which benefits further pharmacology and mechanism research of JTT. © The Royal Society of Chemistry 2016. Source

Mao Y.,Chongqing Medical University | Fang L.,Chongqing Medical University | Ai L.,Chongqing Medical University | Li C.,National Engineering Research Center | And 4 more authors.
PLoS ONE | Year: 2014

Pancreatic cancer is one of the most malignant neoplasms originating in the digestive system. Focused ultrasound (FUS) treatment instead of the surgery operation has been used to treat Pancreatic cancer noninvasively in clinical trials. The endocrine and exocrine glands in pancreas provide the two unique functions for a person to be healthy. It is critically important to find out if the FUS treatment can still keep the normal functions of the two glands. The goal of this study is to examine and analyze changes in histopathology and serum glucose and amylase levels of the targeted in-vivo felines after the FUS treatment. Various percentage volumes of pancreas of felines were insonified. The FUS treatment (7.5 MHz of central frequency; 5 W of acoustical power; transducer f-number = 0.33; 6 s insonification time per point) effectively generated coagulative necrosis at the insonified site while leaving tissue outside the insonified site intact. It was also observed that all felines endured well with the FUS treatment; changes introduced to pancreatic tissue after up to 50% of a pancreas by volume was insonified by the FUS procedure did not affect its normal endocrine and exocrine functions. © 2014 Mao et al. Source

Su H.,Hohai University | Zhang N.,National Engineering Research Center | Wen Z.,Nanjing Institute of Technology | Li H.,Hohai University
Journal of Intelligent Material Systems and Structures | Year: 2016

The concrete strength has the strong influence on service safety of mass hydraulic concrete structures. The real-time identification of concrete strength is very important to ensure the pouring quality during the construction and find timely the hidden troubles in service. Based on the analysis for the mapping relationship between concrete strength and stress wave amplitude, the method is proposed to obtain indirectly the concrete strength with self-made concrete piezoelectric ceramic smart module pairs. First, according to the service condition of hydraulic concrete structure, the concrete piezoelectric ceramic smart module is designed and the process manufacturing concrete piezoelectric ceramic smart module is presented. The protecting measures of piezoelectric ceramic piece, the peripheral material constituent, and the pouring links are introduced. Second, an integrated system, which is composed of self-made concrete piezoelectric ceramic smart modules in pair as sensor and actuator, fuzzy inference system, and other auxiliary equipments, is developed to monitor indirectly concrete strength. Its working principle is studied. Finally, an experiment of hydraulic concrete strength is implemented to demonstrate the feasibility and validity of the proposed method and developed system. The concrete piezoelectric ceramic smart modules in pair are taken as sensor and actuator embedded in hydraulic concrete specimens. The wave-based analysis method is adopted to collect the stress wave amplitude data during the pouring process of concrete specimens. The fuzzy inference approach is utilized to build the mathematical model describing the relationship between concrete strength and stress wave amplitude. Based on the above mathematical model, the concrete strength can be identified indirectly. © SAGE Publications. Source

Wu J.,Nanjing University | Xu Z.,Nanjing University | Zhang W.,Nanjing University | Zhang W.,National Engineering Research Center | And 6 more authors.
AIChE Journal | Year: 2010

Aminated resin (NDA-101) and oxidized resin (NDA-702) were synthesized to remove Dimethyl phthalate (DMP) from the contaminated water. The equilibrium and heat properties in the course of adsorption process were examined and compared with two commercial heterogeneous adsorbents, namely an acrylic ester resin (Amberlite XAD-7) and a coal-based granular activated carbon (AC-750). The associated equilibrium isotherms can be well fitted by Freundlich equation and the adsorption capacities for DMP followed the order: NDA-702 > NDA-101 > AC-750 > XAD-7. The surface of XAD-7 was demonstrated to be relatively homogeneous through surface energy heterogeneity analysis, offering the sole hydrogen bonding interaction. Contrarily, heterogeneous surface of oxidized resins NDA-702 and the aminated resins NDA-101 exhibited a promising adsorption capacity and affinity toward DMP probably derived by multiple hydrogen bonding, Π-Π stacking, and micropore filling interactions. © 2010 American Institute of Chemical Engineers (AIChE). Source

Liu Y.-F.,Beihang University | Guo W.,Beihang University | Guo W.,National Engineering Research Center | Zhang J.,Hefei University | Xu X.-Y.,Beihang University
Journal of Donghua University (English Edition) | Year: 2015

Wet clutch is an important shifting component in automatic transmission, and its properties will affect the gear shift performance. By comparing the calculated and test results, the static friction torque model was proved to be capable of describing the real pressure and torque only in the situation of high-energy engagement. Therefore, a dynamic torque model was proposed on basis of hydrodynamic properties between friction surfaces, in which the clutch engagement was divided into three phases for hydrodynamic lubrication, mixed lubrication, and mechanical contact. The proposed dynamic torque model was validated by comparing the calculated and test results. The effects of temperature, pressure, and pressure changing rate of automatic transmission fluid(ATF) on the clutch torque were analyzed. Based on these results, the clutch-to-clutch torque control during shifting in automatic transmission was optimized, and as a result, the shifting comfort was significantly improved since the problems such as the fluctuation and sudden drop of the engine rotating speed during shifting were eliminated. Copyright © 2015 by Editorial Board of Journal of Donghua University, Shanghai China. Source

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