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An integrated process of supercritical methanol (SCM) and sodium methoxide catalyst was developed to produce fatty acid methyl esters (FAMEs) via continuous esterification from crude biodiesel. The crude biodiesel with high free fatty acid (FFA) content must be refined to reduce the acid value (AV) for meeting the quality standards. The process parameters were studied by Box-Behnken design (BBD) of response surface methodology (RSM). The experimental results revealed that the AV of crude biodiesel decreased from 18.66 to 0.55 mg KOH g(-1) at the reaction conditions of 350 °C, 0.5 % amount of sodium methoxide catalyst, and 10 MPa. Temperature shows the most significant effect on the esterification, followed by pressure and amount of sodium methoxide catalyst. This integrated process proved to be a potential route to refine the crude biodiesel because of its continuity, high efficiency, and less energy consumption with relatively moderate reaction conditions compared with conventional methods.

Background. Recent studies suggest that mutation of the slow delayed rectifier potassium channel (IKs) contributes to familial atrial fibrillation (FAF). In the current study, we identified common genetic variants ofKCNQ1and explored the potential association betweenKCNQ1polymorphism with lone AF (LAF).Methods. Clinical data and blood samples were collected from 190 Han Chinese patients with sporadic AF and matched healthy controls. Variants of theKCNQ1gene were identified using single-strand conformational polymorphism (SSCP) analysis. A case-control association study inKCNQ1identified six known single-nucleotide polymorphisms (SNPs) during SSCP screening of the 190 LAF patients and 190 healthy controls.Results. One of the SNPs inKCNQ1was strongly associated with LAF; significant allelic association was detected rs59233444 (P=0.013,OR=1.469, 95% confidence interval (CI): 1.083–1.993). A multiple regression analysis indicated that rs59233444 is an independent risk factor for LAF. Twelve new variants were identified inKCNQ1, including one in the 5′-UTR, two in the 3′-UTR, six in introns, two synonymous substitutions, and one missense substitution. Variants c.1009C>T, c.1860C>T, and c.+2285C>T were not present in the 190 controls, and the others were identified in controls at various frequencies.Conclusions. rs59233444, a common SNP but not mutation in the coding regions of theKCNQ1gene, is a risk factor for LAF in Chinese Han population.

We have measured the AC impedances of blood samples from 30 healthy adults with the Agilent 4294A impedance analyzer at frequency ranging 0.01-100MHz. At the same time, we measured the erythrocyte sedimentation rate (ESR), hematocrit (HCT), plasma fibrinogen (FIB), blood glucose (BG) and D-dimer. Then we analyzed the correlation between ESR and dielectric parameters of blood by linear correlation analysis, and used multiple regression analysis to reveal the influence of these hematological data on dielectric spectral characteristics of whole blood cell when these data were available. Statistical analysis showed that ESR had a linear correlation with the part of dielectric parameters in whole blood cell. The Multiple linear regression analysis indicated that HCT and BG had an influence on dielectric spectral characteristics of human whole blood cell, and HCT was the major factor in haematological parameters that influenced dielectric spectral characteristics of whole blood cell.

Because of query's semantic ambiguity, search process of general SE can not meet the personalized demand of users concerning personal interests and professional backgrounds. To resolve this problem, a new personalized user-query semantic clustering approach is proposed in this paper. The search engine user logs are valuable resources which obtain the rich history information of user access records which reflect the user's interests and domain knowledge. For every specific user, we get three semantic relationships between user-query and their search click information, such as query contents, Click sequence and selected documents. In this way, user-query semantic similarity can be calculated using search click information, then user- query can be clustered and disambiguated based on user's interests. Through the personalized query clustering to guide topic crawling, you can concentrate on more in-depth in the user's interesting field.

For improving previous compressor impeller's machining efficiency, the new process routine and tool parameters were adjusted by using high speed machining(HSM), which can decrease machining time and the types of tools. The high efficient machining process was proved by tests, and it had been shown that the time of machining was shorter. Improvement measures were taken to deal with the problems of vibration ripples which occurs in the improvement process.