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This paper delineates a case study analyzing and forecasting of the outpatient visits frequency of a hospital in Zhengzhou, China. By evaluating the annual out-patient data throughout the year of 2015, this paper applies the “Day” as timescale and carries out the experiment so as to forecast the number of visiting patients with the impact of the “Week” taken into consideration. Two models are used separately: the Autoregressive Integrated Moving Average (ARIMA) with seasonal index and the Seasonal Autoregressive Integrated Moving Average (SARIMA). Based on the empirical findings from the comparison of the fitting effect and forecasting effect of the above two models, it is clear that SARIMA reaches a satisfactory outcome: it displays optimum indexes. Therefore it is preferable to deploy the SARIMA model to proceed a forecasting of outpatient visits for medical institutions. Meanwhile the paper also aims to provide management of medical institution with theory grounds of working and personnel arrangement and insight so as to make a prompt and reasonable contingency plan when it comes to sudden disease.

Fatty acids (FAs) are associated with a series of diseases including tumors, diabetes, and heart diseases. As potential biomarkers, FAs have attracted increasing attention from both biological researchers and the pharmaceutical industry. However, poor ionization efficiency, extreme diversity, strict dependence on internal standards and complicated multiple reaction monitoring (MRM) optimization protocols have challenged efforts to quantify FAs. In this work, a novel derivatization strategy based on 2,4-bis(diethylamino)-6-hydrazino-1,3,5-triazine was developed to enable quantification of FAs. The sensitivity of FA detection was significantly enhanced as a result of the derivatization procedure. FA quantities as low as 10 fg could be detected by high-performance liquid chromatography coupled with triple-quadrupole mass spectrometry. General MRM conditions were developed for any FA, which facilitated the quantification and extended the application of the method. The FA quantification strategy based on HPLC-MRM was carried out using deuterated derivatization reagents. "Heavy" derivatization reagents were used as internal standards (ISs) to minimize matrix effects. Prior to statistical analysis, amounts of each FA species were normalized by their corresponding IS, which guaranteed the accuracy and reliability of the method. FA changes in plasma induced by ageing were studied using this strategy. Several FA species were identified as potential ageing biomarkers. The sensitivity, accuracy, reliability, and full coverage of the method ensure that this strategy has strong potential for both biomarker discovery and lipidomic research.

通过膜层设计理论设计出以K9玻璃为基底的兼具高透过率和高耐摩擦性的三层宽带增透膜, 并通过溶胶-凝胶技术成功制备了所设计的增透膜. 以正硅酸乙酯(TEOS)和钛酸丁酯(TTIP)为前驱体、以盐酸为催化剂制得SiO 2 和TiO 2 溶胶. 将两种溶胶按一定比例混合得到SiO 2 -TiO 2 复合溶胶. 实验结果表明: 三层增透膜在可见光区的平均透过率达到98.7%, 与未镀膜的K9玻璃基片相比提高了7.1%. 增透膜经较强机械摩擦后透过率基本保持不变, 表明该增透膜具有优良的耐摩擦性. 采用六甲基二硅氮烷(HMDS)对增透膜表面进行进一步的修饰, 修饰后增透膜与水的接触角提高至94.3°, 增透膜的疏水性及环境稳定性得到较大的提高.

Mg and Ti ions co-doped (Li0.98Mg0.01)(Fe0.98Ti0.01)PO4/C cathode material for lithium-ion batteries was prepared by a solid-state method under N2 atmosphere. The samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and galvanostatic charge-discharge test. Results indicated that Mg and Ti ions co-doping remarkably improved the electrochemical performance of LiFePO4, including rate capacity, temperature behavior, and cycling stability. Discharge capacities of 154.7 and 146.9 mAh·g - 1 were obtained at the rates of 0.2C and 1C for half-cell tests, respectively. For 60 Ah full-cell tests, 100% of 1C capacity was maintained even at 3C rate, 89.7% and 63.1% of initial capacity at room temperature were retained at 0 and-20 °C, respectively. 89%

LiCo0.2Ni0.4Mn0.4O2, as the cathode material for lithium ion batteries, was modified by TiO2-coating. The effect of TiO2-coating on the structure and electrochemical performance of LiCo0.2Ni0.4Mn0.4O2 was characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and galvanostatic charge-discharge tests. The results suggest that a small amount of TiO2-coating does not change the crystalline structure, but considerably improves the electrochemical performance of LiCo0.2Ni0.4Mn0.4O2 in terms of capacity delivery and cyclability. XPS measurements confirm that the improved electrochemical performance is most possibly attributed to a decrease in interaction between the layered material and non-aqueous electrolyte during the charge-discharge processes.

For a successful company, which is facing fiercely competitive environment with limited customer resource, achieving efficiently customer segmentation so as to apply high quality recommendation strategies is a key task. Ant colony clustering based on customer value is a novel method for efficiently approaching customer segmentation. Additionally, experience shows that customer behavior patterns will change over time, accordingly, customer segments must change also, however, until now, much research on customer has resumed that customer segments are stable, in order to track of customer shifts among segments, this study proposes incremental clustering method. Empirical study demonstrates that this approach can supplies scientific ground for enterprises to check their service strategies and discoveries customer missing in time.

The retention behaviour of the complexes of rare earth elements, thorium and chromium with 2-(2- arsenophenylazo)-1,8-dihydroxy-7-(2,6-dibromo-4-fluorophenylazo)naphthalene-3,6-disulphonic acid was studied. Precolumn derivatization was used. The stationary phase was ODS-bonded silica and the mobile phase was methanol-water-tetrabutylammonium bromide. The detection limits are 2 ng ml−1 for total rare earths, 2.5 ng ml−1 for thorium and 10 ng ml−1 for chromium. The tolerance of foreign ions is very high. The method can be applied satisfactorily to ore samples and rocks.