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The development of volatile compounds and their precursors during the dehydration process of membrane-clarified sugarcane juice to non-centrifugal sugar (NCS) was investigated. Head-space solid phase microextraction/gas chromatography–mass spectrometry (HS-SPME/GC–MS) coupled with chemometrics was employed to assess the differences at the various stages of the dehydration process. A total of 111 volatile compounds were identified, among which 57 were endogenous compounds from sugarcane juice and displayed an attenuated abundance in the first 30 min. Typical oxygen and nitrogen heterocyclic compounds, including furans and pyrazines, and aldehydes derived were found to be the main volatiles contributing to the formation of NCS characteristic aroma, with phenols, alcohols, esters, acids, and sulfur compounds as supplementary odor. Free amino acids and reducing sugars were identified as important precursors for the aroma development process. The low temperature (90–108 °C) and micro vacuum condition (−0.03 MPa) approach used in this study could be an alternative option for the manufacture of NCS.

BackgroundThe patterns of blood pressure trajectory (i.e., change over time) over life-course remain to be explored. In this study, we aim to determine the trajectories of systolic blood pressure (SBP) from adulthood to late life and to assess its impact on the risk of cardiovascular diseases (CVDs).MethodsBased on the China Health and Nutrition Survey, a total of 3566 participants aged 20-50 years at baseline (1989) with at least three SBP measurements during 1989-2011 were included. SBP was measured through physical examination, and socio-demographic factors, lifestyles, medications, and CVDs were based on self-reported questionnaire. Latent class growth modeling was performed to examine SBP trajectory. Odds ratio (OR) and 95% confidence interval (CI) from logistic regression was used to determine the association between SBP trajectory and CVDs.ResultsFive trajectory groups of SBP were identified: Class 1: rapid increase (n = 113, 3.2%); Class 2: slight increase (n = 1958, 54.9%); Class 3: stable (n = 614, 17.2%); Class 4: increase (n = 800, 22.4%); Class 5: fluctuant (n = 81, 2.3%). After adjustment of demographic factors, baseline SBP, and lifestyles, compared with the "slight increase" group, the OR (95% CI) of CVDs was 0.65 (0.32, 1.28) for "stable" group, 2.24 (1.40, 3.58) for "increase" group, 3.95 (1.81, 8.62) for "rapid increase" group, and 4.32 (1.76, 10.57) for "fluctuant" group. After stratified by use of antihypertensive drugs, the association was only significant for "rapid increase" group among those using antihypertensive drugs with OR (95% CI) of 2.81 (1.01, 7.77).ConclusionsHaving a rapidly increasing SBP over life-course is associated with a higher risk of CVDs. This implies the importance of monitoring lifetime change of blood pressure for the prevention of CVDs.

In this study, the effects of ultrasonic parameters on the synthesis of sucrose laurate were investigated under four frequencies (20, 33, 53, and 80 kHz). Results indicated that low ultrasonic frequency increases sucrose monolaurate yield, whereas high ultrasonic frequency increases sucrose dilaurate yield. As the sound intensity increases from 0.55 to 1.04 W cm−2, the yield of sucrose laurate also increases, whereas the reaction time decreases. The yield of sucrose laurate decreased, and the reaction time prolonged with the decreasing pulse width. Both the initial production rate of sucrose monolaurate and the yield of sucrose dilaurate increased with the increasing temperature from 60 to 90 °C. However, further increase in the reaction temperature did not increase the yield of sucrose monolaurate but significantly reduced the reaction time. Sucrose laurate synthesized under ultrasonic frequency consisted of sucrose monolaurate, dilaurate, and polylaurate.

To research on the equivalent of perforating through LY12CZ aluminum alloy plates and 2π armor steel, based on the rule that the ultimate velocity, the penetration process of tungsten sphere into LY12CZ aluminum alloy plate and 2π armor steel plate was simulated with LS-DYNA finite element code, the numerical results corresponded well to previous experimental observation. The expression between LY12CZ aluminum alloy plate and 2π armor steel plate impacted by a tungsten sphere was presented through analyzing the numerical results. Introduction A lot of experiments often were required to target vulnerability research, and a lot of time and cost to adopt the whole true experiment, if the various armor protection level could be substituted by equivalent target, a lot of the experimental expenses and costs will be saved. In view of the two common armor materials, the protection level of aluminum alloy was equivalent by standard homogeneous steel. Numerical simulation is one of the main means of this kind of problem, It can greatly save the cost and shorten the research period by means of numerical simulation and the experimental correction[1]. Based on the principle of the equal ultimate velocity, the numerical simulation was used to the aluminum alloy target and the homogeneous target penetrated by the fragment through the finite element software LS-DYNA, and the equivalent relations of the aluminum alloy target and the homogeneous steel target was preliminary study. Equivalence Principle The two kinds of principle can be chosen for the equivalent of the plate impacted by fragment: the ultimate velocity method and the residual penetration method. From the evaluation of the power of ammunition, the ultimate velocity method was chosen, from the evaluation of the ability of target anti-damage, the residual penetration method was generally chosen. The ultimate velocity method was selected in this paper. The H1 thickness of aluminum alloy target and the H2 thickness of homogeneous steel target was penetrated by spherical fragment, and the same V50 of ultimate velocity was obtained on two kinds of target, so the H1 thickness of aluminum alloy target and the H2 thickness of homogeneous target was equivalent. The equivalent diagram of aluminum alloy target and homogeneous target as shown in Fig.1. International Conference on Materials, Environmental and Biological Engineering (MEBE 2015) © 2015. The authors Published by Atlantis Press 404 Spherical fragment H1 Homogeneous steel H2 Aluminum alloy Fig. 1 Equivalent diagram of aluminum alloy target and homogeneous target Numerical simulation Geometric modeling Experiment for reference to construct equivalent target model, material and size of fragment based on the literature[2], and combining the model shown in Fig. 1: (a)Target model: the materials of spherical fragment was tungsten alloy, the diameter was 10mm; The materials of plate was LY12CZ aluminum, the size was 100mm×100mm×10mm; (b)Equivalent target model: the size and material of fragment was the same as the target model, the materials of the plate was 2π armor steel, the size was 100mm×100mm×6mm. The constitutive model of fragment was Plastic_Kinematic[3], and the LY12CZ aluminum alloy and 2π armor steel was Johnson_Cook[3]. The symmetric plane was applied by boundary conditions, and a quarter of the overall model was used calculated based on the symmetry of the model. The nonreflect boundary condition was applied on the border around based on ignored the influence of boundary of stress wave. The meshing model was adopted by the 3d Solid164, and the target contact part of the unit was fine in order to reduce the computing time. The finite element calculation model was shown in Fig. 2. (a) Target model (b) Equivalent target model Fig. 2 Finite element model of calculation Results and analysis of simulation The 10mm diameter spherical tungsten alloy fragment with 440 m/s and the 450 m/s vertically impacted on 6mm thickness armor steel plates, the curve and the impact process of the fragment velocity as shown in Fig. 3 and Fig. 4. Fig. 3 State and velocity curve of spherical tungsten alloy fragment vertically impacted on 6mm thickness armor steel at 440m/s