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In order to improve the economic utilization of quinoa bran and develop a safe and highly available zinc ion biological supplement. In this study, a four-factor, three-level response surface optimization of quinoa bran soluble dietary fiber (SDF) complexation of zinc was studied. The effect used four factors on the chelation rate was investigated: (A) mass ratio of SDF to ZnSO4.7H2O, (B) chelation temperature, (C) chelation time, and (D) pH. Based on the results of the single-factor test, the four-factor three-level response surface method was used to optimize the reaction conditions. The optimal reaction conditions were observed as mentioned here: the mass ratio of quinoa bran SDF to ZnSO4.7H2O was 1, the reaction temperature was 65°C, the reaction time was 120 min, and the pH of the reaction system was 8.0. The average chelation rate was 25.18%, and zinc content is 465.2 μg/g under optimal conditions. The hydration method rendered a fluffy quinoa bran SDF structure. The intramolecular functional groups were less stable which made the formation of the lone pairs of electrons feasible to complex with the added divalent zinc ions to form a quinoa bran soluble dietary fiber-zinc complex [SDF-Zn(II)]. The SDF-Zn(II) chelate had higher 2,2-diphenylpicrylhydrazyl (DPPH), ABTS+, hydroxyl radical scavenging ability, and total antioxidant capacity. Therefore, metal ion chelation in dietary fiber is of biological importance.

[Objectives] In order to solve the wear problem of ship decks caused by major equipment, a new highly wear-resistant anti-skid deck coating is developed.[Methods] The coating is mainly composed of a primer,non-skid layer and topcoat. The non-skid wear performance of the coating was tested by sliding a wear tester. The friction and wear behavior of the coating under different working conditions(dry,wet and oily)was studied.[Results] The results show that the friction coefficient of the coating under different working conditions decreases with the increase of the wear number,and the friction coefficient is lowest under oily conditions,which is mainly related to the lubrication of aviation kerosene; the wear loss rate of the coating increases with the increase of the wear number,and the wear mechanism is mainly abrasive wear in the initial wear stage and adhesive wear in the stable wear stage.[Conclusions] The research results can not only guarantee service safety of the marine structure,but also provide theoretical basis for the development and application of new non-skid deck coatings.

To explore the influence the rail pad structure of the DT-III fastener system on the clip modal analysis, the finite element model of the DT-III fastener system was established. By adjusting the width and depth of the rail pad groove, the clip assembly modal responses with different rail pad structures are obtained. The results show that the groove depth and width of the rail pad have great influence on the fastener system stiffness. In the assembly state of the clip, with the increase of the groove depth and width of the rail pad, the first-order mode frequency of the clip decreases gradually, and the frequency range is 850Hz-930Hz. Therefore, the rail pad structure can be reasonably designed based on the rail corrugation and train speed.

Although earthquake prediction is a big challenge in the world, some simple observational tools can capture many physical signals and demonstrate that an earthquake (EQ) may be forthcoming in short period. Many researchers have studied the significant variation of atmospheric electrostatic field related to the forthcoming earthquake. However, until now, there is not a compelling physical mechanism which can explain why atmospheric electrostatic abnormal signal could appear just before an earthquake. Here we present a precursor signal and propose a brief physical interpretation. Under fair air conditions, if the near-surface atmospheric electrostatic field Ez (oriented down when it is positive) presents a very stable negative anomaly (from -100 V/m to -5000 V/m), it will forebode that an earthquake (seismicity from 3-8) would take place in the next several to tens of hours within a distance less than 100 km. We name this prediction technique as "DC Ez Determination"(DED). In addition, the mechanism of such abnormal quasi-static electric field before a forthcoming earthquake has been proposed here: (1) Radon gas releases from the rock clefts near the epicenter during seismogenic process. (2) {\alpha} particles are produced due to the radioactive decay of Radon gas in the air. (3) {\alpha} particle ionizing radiation creates more positive particles in the air, which is much more effective than that {\beta} and {\gamma} particles produced during Radon radioactive decay. (4) The new positive particles change formal positive atmospheric electric field (Ez) into stably negative near the earth-surface. (5) The closer the instrument is to the epicenter, the more likely it is to observe the negative Ez signal related to the earthquake. It is recommended to establish an instrument network to capture the reliable precursor and make some warnings before the earthquake disaster., Comment: 18 pages, 3 figures, 2 supplementary figures

The Reed-Solomon (RS) (255,223) code is a powerful burst error correcting code, and it can correct any combination of 16 or fewer RS symbols in error per codeword. Based on the Berlekamp's bit-serial multiplication algorithm, we design and implement a sounding rocket-borne RS (255, 223) encoder with 2-depth symbol interleaving capability. The implementation result of the encoder on single-chip Xilinx FPGA XC3S400 is presented. The encoder is tested by three classes of RS symbols, and the test results indicate that the designed RS (255, 223) encoder is highly efficient and suitable for applying on sounding rocket missions.

Enzymes, as biological catalysts, have been used extensively as processing aids in the food industry for the past several decades. They help to achieve desired attributes such as texture, color, flavor, and other important qualities of food materials, thus enabling raw materials and ingredients to be transformed into finished products. Compared with most traditional methods, utilization of enzymes in food processing provides a greener food chemistry approach as enzymes are natural proteins and have very high selectivity and specificity. The chapter provides detailed information on enzymatic modifications of foodstuffs and is structured in four main parts to answer the following questions (1) What are the major sources of enzymes? (2) What are their key properties? (3) How are they used in food processing? and (4) How can they be controlled when used in the development of food products and ingredients? The mode of action of the major enzyme groups (i.e., oxidoreductases, transferases, proteases, carbohydrases, lipases, and isomerases) is discussed in detail. In addition, for each group, examples are given of particular uses of the enzymes in the food and feed industries. The impact of different conditions, that is, temperature, pH, and inhibitors, as well as water activity on enzymatic activity of the different enzymes, is further provided.