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Considering the low conversion and long reaction time in scaling up reaction in batch reactor, the organocatalyzed epoxidation reaction of styrene was intensified under continuous flow conditions using a commercial fluidic reactor (Corning Advanced Flow G1 Reactor). After investigating the effect of reaction temperature, catalyst amount, MeCN/t-BuOH ratio, FO/FAB (buffer solution amount), total feed flow rate and operating mode on the epoxidation reaction, the optimal reaction conditions were identified under continuous flow conditions. Upon optimization, high conversion and excellent selectivity with short reaction time (3.17 min) can be obtained. We successfully developed a process for the rapid and continuous epoxidation of styrene using an organocatalyst with hydrogen peroxide as the oxidant. Compared with the batch conditions, the continuous flow reactor can exhibit unique advantages including high-speed, safety, continuousness and absence of amplifying effect, which will be significant for the industrial production of epoxides.

Writing a Tang-Dynasty poetry in Chinese is very popular and useful in the tradition Chinese culture education field, In this paper we use GitHub open sources “jieba” Algorithm for text segmentation of Chinese Tang Dynasty poetry and database methods to auto-generate Chinese old Tang-Dynasty poetry, focus on AI for education field and poetry making project, through Chinese word semantic matching, short sentence combination and verse rhyme pattern rules.

This paper presents the use of vibration analysis based on autoregressive (AR) trispectrum in milling process to indicate the relationship between machined surface quality of workpiece and spectrum character under a variety of different cutting parameter settings, such as the depth of cut, the feed rate and the spindle speed. The metal cutting experiments were performed on steel A3 material without using any cutting fluid. The experimental results for slices analysis of trispectra indicated that the spectral peaks were abundant as the milling process went smoothly. The roughness value measured reflects the machined surface quality of workpice. According to the changes for spectral peak and roughness value, a conclusion was made that the proposed trispectrum slices method for choosing cutting parameters and monitoring the machined surface quality in milling process was practicable.

The operating principle of measuring rheological properties of magnetorheological(MR) fluid was expounded by means of a new rheometer with double driving discs rotating at the same speed in the opposite directions. The constitutive equation of MR fluid was established with theoretical analysis from experimental data. The conventional power spectrum approach was unable to detect the existence of quadratic phase coupling for dynamic rheological measurement. Bispectrum analysis is emerging as a new powerful technique in signal processing, which can describe nonlinear coupling, restrain Gaussian noise and reserve phase component. An autoregressive(AR) model of the third order cumulant, the bispectra and bispectral contours were utilized for analyzing the dynamic characteristics of the MR rheometer by merely using the sampled output torque signals when a zero mean non-Gaussian white noise interferes with the rotary disc system. The measurement and analysis process based on virtual instruments were automatically controlled by computer in this paper. The experimental and theoretical results show that rheological properties and dynamic characteristics of MR fluid can be measured with this double disc rheometer.

Phytochemical investigation of the aerial parts of Chimonanthus salicifolius resulted in the isolation of two sesquiterpenoids, 8α-hydroxy-T-muurolol and (1α,6β,7β)-cadinane-4-en-8α,10α-diol, together with 13 known compounds. The 15 structures were established by means of 1D and 2D NMR spectroscopy. The relative and absolute configurations of 8α-hydroxy-T-muurolol and 8α,11-elemodiol were achieved by NOESY experiments and X-ray crystallography using CuKα radiation. 8α-hydroxy-T-muurolol and (1α,6β,7β)-cadinane-4-en-8α,10α-diol showed immunosuppressive activities in a dose-dependent manner.

The evaporation and heat transfer of thin liquid film are crucial factors affecting on the heat transfer performance of boiling bubbles or slugs. For boiling in micro-channels, the flash evaporation of the liquid film may give rise to boiling instability, and the dry-out of the film leads to serious deterioration of the heat transport. The thin liquid film has multi-scale transitions, and hence the phase change and fluid dynamics need to be solved by special governing equations and numerical algorithm. The numerical studies to date have solved the steady state distribution of the film, but the difficulty consists in the transient simulation of time-variant liquid films. In the present study, unsteady form governing equations are developed. With inclusion of the temporal terms, we conducted transient simulations for flat liquid films formed during the flow boiling in micro-channels. The model predicts the developing of drying spot during growth of elongated bubbles. The results show that the film thickness and distribution change quickly in a growth period, which are functions of the heat flux, mass flow rate and the other parameters. The quantitative assessment of these effects helps to clarify the mechanism of boiling instability and the conditions for the occurrence of critical heat flux (CHF). The simulation needs special numerical scheme for time marching and stabilization treatment for the nonlinear terms, where the numerical accuracy and the significance of the temporal effects are also discussed.Copyright © 2013 by ASME

Figures 3 and 4 were incorrectly switched. The image currently appearing as Figure 3 belongs with the title and legend for Figure 4, and the image currently appearing as Figure 4 belongs with the title and legend for Figure 3. The titles and legends are in correct order.

To find out HepB vaccine timely delivery factors influencing in newborns within 24 hours, provide a basic evidences for increasing the coverage of timely HepB vaccine.We established multinomial Logistic regression equation to analysis the factors with the investigation landform, delivery rate at hospital, occupation and education of child caretakers, ethnic,whether the child caretakers know children need vaccination and if the child caretakers bring children for vaccination.234 children received timely birth dose HepB among 852 children, timely coverage rate was 27.46%. Compare with 6.71% of children delivery at home, timely coverage of children delivery at township clinic and county clinic hospitals are 46.86% and 54.05% respectively. Multinomial logistic regression analysis showed that delivery hospitals (X1), education of child caretakers (X2) were the main influencing factors to the timely birth dose HepB vaccination, the investigation landform, occupation of child caretakers, ethnic, whether the child caretakers know children need vaccination and if the child caretakers bring children for vaccination on their own have relevancy with the timely to the timely birth dose HepB vaccination.The strategies such as increasing the rate of delivery at hospitals and putting more funding into publicity will facilitate increasing the coverage of timely birth dose HepB vaccination.

Type selection and operational suitability test of model are two basic aspects of time series modeling. Ascertaining the order of time series model is the key problem of suitability test. Some traditional order selection criteria haven’t yet been adapted for ascertaining an optimal model order. In this paper, a new Singular Value Decomposition (SVD) method for determining the order of an autoregressive (AR) model was presented and compared with traditional order selection methods, i.e. Final Prediction Error(FPE), Akaike Information Criterion(AIC), Bayesian Information Criterion(BIC) and SVD Slicing, according to AR bispectrum analysis of vibration signals derived from the faults of the hydraulic valves. With simulation experiments, the order determined by traditional order selection methods was too low and the fault information could not be discriminated clearly in comparison with Frobenius normalized norm method of SVD. Considering the above situation, it has been drawn as a conclusion that the proposed new method outperforms the traditional order selection methods.

A worm-like specimen recovered from a patient previously identified as Armillifer sp. in the city of Yulin, Guangxi Autonomous Region. After comparative analysis of habitat (serpents as final hosts and human being as accidental intermediate host) and body size of the 4 known pathogenic pentastomid species of Armillifer (A. agkcistrodontis, A. armillatus, A. grandis and A. moniliformis) with the recovered specimen, the present authors consider that the recovered specimen has been misidentified as Armillifer sp. The recovered specimen probably belongs to a nasal leech.

The mechanism of inhibiting telomerase activity by telomerase inhibitors is very complex, and involves common actions of many proteins. This study was to investigate the effects of 3'-azido-deoxythymidine (AZT) on telomerase activity and protein expression of hepatocarcinoma cell line SMMC-7721, and explore possible mechanism of inhibiting telomerase activity in SMMC-7721 cells by AZT.Optimized concentration and treatment time of AZT were detected by MTT assay. After treatment with AZT, the telomerase activity in SMMC-7721 cells was detected by real-time fluorescent quantitative TRAP (FQ-TRAP) assay; the apoptosis of SMMC-7721 cells was detected by TUNEL assay and flow cytometry (FCM); the changes of specific proteins were monitored by raman spectra assay and surface-enhanced laser desorption time of flight-mass spectrum (SELDI-TOF-MS) with protein chip assay.The optimized treatment time of AZT was 48 h, and the optimized concentration of AZT was 20 mmol/L. When treated with 20 mmol/L AZT for 48 h, the telomerase activity in SMMC-7721 cells was inhibited by 53.85% of control (P0.001); apoptotic morphologic changes of SMMC-7721 cells were observed; the apoptosis rate of SMMC-7721 cells was 13.5%; 7 spectral peak of proteins were changed; 24 proteins were up-regulated and 8 were down-regulated in SMMC-7721 cells. All of the 32 distinct proteins were small molecular proteins.AZT can inhibit the telomerase activity and induce apoptosis of SMMC-7721 cells, which is related to specific small molecular proteins.