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The realization method of electron beam surfi-sculpt on Ti-6Al-4V alloy was studied. Surfi-sculpt could be obtained by tailored scanning waveform based on the new scanning control system, and then the protrusions with no less than 2 mm in height were got on the metal surface. By the method, the different profiles of the protrusions were tried from different scanning waveforms and frequencies and the microstructure of protrusions was analyzed. The results show that six lines meeting waveform is the best way to get protrusions, while proper frequency is also a key factor to realize the surfi-sculpt process. The microstructure of the protrusion could be divided into four parts, which are edge zone, central zone, HAZ and base metal. [ABSTRACT FROM AUTHOR]

Species discrimination among three kinds of puffer fish, Takifugu obscurus, Takifugu flavidus and Takifugu rubripes, was conducted using an electronic nose combined with olfactory sensory evaluation. All data were treated by multivariate data processing based on principal component analysis (PCA) and discriminant factor analysis (DFA). The results showed the discriminant model by PCA method and DFA method. Using PCA and DFA, it was shown that the electronic nose was able to reasonably distinguish between each of the eleven puffer fish groups, with a discrimination index of 85. The olfactory sensory evaluation was undertaken in accordance to Sensory analysis-Methodology- Initiation and training of assessors in the detection and recognition of odors (BS ISO 5496- 2006), and the results showed that the evaluation was able to identify puffer fish samples according to their species, geographical origin and age. Results from this analysis demonstrate that the E-nose can be used to complement the discrimination of odors by sensory evaluation from the three species of puffer fish studied here. [ABSTRACT FROM AUTHOR]

Chymotrypsin digestion and Circular dichroism (CD) spectroscopy were used to study the structural stability of myosin rods prepared from silver carp in summer and winter. Differences in the thermal stability were clearly demonstrated by the chymotryptic digestion patterns and CD data obtained at pH 7.5 in 0.5 M KCl for myosin rods in both seasons, indicating the structural properties differed seasonally. In winter, the myosin rods were more susceptible to be cleaved into short (40 kDa) subfragments when digested at high temperature (30 °C). The major peaks in unfolding profiles showed that transition temperatures for the rods were 35 °C in winter, and 36 and 41 °C in summer. Rod subfragments (S-2 and LMM) were isolated and further analyzed by CD. In both winter and summer, the LMM fragments showed an unfolding transition at around 35.5 °C, but the S-2 fragments showed large seasonal difference; in winter, they showed a major unfolding peak around 35 °C and a minor peak at 40.5 °C, while in summer, they unfolded mostly at 44.5 °C, which was 8 °C higher than that for the LMM fragments. Short (40 kDa) S-2 subfragments isolated from winter rods gave a single unfolding transition at 41 °C. These results suggest that differences in the thermal stability of myosin rods between winter and summer were due to differences in the stability of S-2 region. The aim of this study was to detect the differences in the structure thermal stability of myosin rods between summer and winter, which is a very important portion for gel formation. The information will be very useful for producing surimi from freshwater fish species in different seasons. [ABSTRACT FROM AUTHOR]

Abstract??The infrared ray propagation model of finite size flat beam in biological tissue is set up. Gaussian beams and circularly flat beams were compared. The model is simulated with Monte Carlo method, and the influence of parameters of biological tissue and properties is analyzed. The potential application of the model is demonstrate by estimating the absorption and transport-corrected scattering coefficients from reflectance measured from intact tissue. [ABSTRACT FROM AUTHOR]

Abstract: Near-IR radiation is often utilized to detect the properties in tissues, up to now, a semi-infinite medium photon migration model and a two-layered turbid medium model are applied widely. In this paper, we set up the steady-state photon diffusion model of three-layered mismatched medium. We utilize the diffuse equation to solve a three-layered mismatched medium and obtain the accurate solution of a three-layered mismatched medium of the steady state in tissue. We find that the solution of a three-layered mismatched medium diffusion equation not only accord with the Monte-Carlo simulation, but can still solve the problems of a two-layered turbid medium model. [ABSTRACT FROM AUTHOR]

Abstract Near-IR radiation is often utilized to detect the properties in tissues, up to now, a semi-infinite medium photon migration model and a two-layered turbid medium model are applied widely. But the solution is approximate. In this paper, According to the diffusion equation, employing the extrapolated boundary condition, we analyze the diffusion of photons of a three-layered matched medium, set up the accurate solution of the diffuse equation. In order to validate our solution, we apply the Monte-Carlo simulation of the time domain and the steady-state, we find that the solution of a three-layered matched medium diffusion equation not only accord with the Monte-Carlo simulation. The solution can still solve the problems of a two-layered turbid medium model and a semi-infinite medium photon migration model [ABSTRACT FROM AUTHOR]

Flavor, especially odor, is one of the most concerning food qualities for producers and consumers. The odor of E. sinensis is a vital quality indicator and highly variable in species, diets, regions and harvest seasons. These differences could diminish consumer acceptance and reduce the economic returns to the farmer. Until now, 168 volatile compounds have been identified in E. sinensis, of which 42 are shared to five edible parts, and the hepatopancreas has 22 specific compounds. The 30 aroma-active compounds may interact to form odor profiles. Volatile compounds are mainly derived from Phosphatidylethanolamine (PE) and free fatty acids (FFA) by a series of biochemical reactions such as thermal degradation, secondary degradation, molecular rearrangement, and Maillard reaction. The odor of crab has a close relationship with agriculture. Once harvested, the crab also produces odors during processing and storage, which could be controlled by consumers. This work provides information that could support the development of innovative aquaculture strategies to satisfy the needs of the consumer market. [ABSTRACT FROM AUTHOR]

As a new type of thermoelectric (TE) material, full-Heusler compounds have aroused widespread interest, for its ultralow lattice thermal conductivity. The first-principles calculations and Boltzmann transport theory are used to study the TE transport properties of n-type doped full-Heusler compounds X2YAu (X = Sr, Ba; Y = As, Sb). At room-temperature, the calculated lattice thermal conductivities are 1.02, 0.89, 0.79, and 0.53 W/mK for Sr2AsAu, Ba2AsAu, Sr2SbAu, and Ba2SbAu, respectively. The ultralow κL is mainly by the extremely low uq and relatively high 1=q. By combining the calculated TE transport coefficients, we get the excellent dimensionless TE figure of merit zT of X2YAu (X = Sr, Ba; Y = As, Sb). The calculated zT of Sr2AsAu, Ba2AsAu, Sr2SbAu, and Ba2SbAu are 0.89, 0.59, 1.55, 0.87 at 300K and 3.35, 2.15, 4.45, 2.91 at 700 K, which indicate that X2YAu (X = Sr, Ba; Y = As, Sb) are potential and excellent TE materials. [ABSTRACT FROM AUTHOR]

BSTRACT: Chicken bouillon is well accepted all over the world, but dried bonito stock is only preferred by the Japanese, and only the Japanese use dried bonito as material for soup stock. To learn the reason, we compared the sensory responses to the taste of dried bonito stock and the chicken bouillon by employing Japanese and Chinese as panelists for sensory evaluation. The descriptive terms were 1st designed and used for sensory analysis of food action rate scaling and paired comparison. The Japanese panel evaluated dried bonito stock as less greasy, no odd taste, weaker in fishy flavor, more well-balanced taste, and preferable to chicken bouillon. The Chinese panel evaluated dried bonito stock as less greasy, stronger in odd taste, stronger in fishy flavor, less well-balanced taste, and less preferable to chicken bouillon. [ABSTRACT FROM AUTHOR]

In this study, the effects of chemical refining on the physicochemical indices, environmental pollutants, lipid functional groups, relaxation characteristics, fatty acid profiles, and triglyceride (TG) molecular species in crude oil extracted from small fish in Mauritania were evaluated. The acid, peroxide, and iodine values of crude oil were identified as 5.52 mg KOH/g, 1.73 meq/kg, and 200.78 g/100 g oil, respectively. After refining, these values were determined to be 0.29 mg KOH/g, 0.76 meq/kg, and 210.80 g/100 g oil, respectively. The polychlorinated biphenyls and arsenic content of crude oil were identified as 32.30 µg/kg and 1.00 mg/kg, respectively. After refining, these were not detected. The content of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) accounted for as much as 87.55% of the polyunsaturated fatty acids in the refined oil, indicating that high-quality fish oil is suitable as a food supplement. The correlation coefficient of the infrared spectra before and after refining was 0.968, and the relaxation time and peak shape data were almost similar before and after purification. Meanwhile, there were no significant differences (P ≥ 0.05) in fatty acid profiles between the crude and refined oils, except for C16:0 (P < 0.01). Based on UPLC-Q E-MS/MS detection, 137 TG molecules were identified in both crude and refined oils. Among the detected TG molecular species, 64 contained EPA or DHA, which accounted for 46.83% and 46.00% of the total TG content in crude and refined oils, respectively. After refining, the content of the molecular species decreased by 31.95 mg/10 g, among which the three most variable molecular species were TG (16:0/18:1/22:6), (16:1/16:2/18:1), and (18:4/16:0/20:5), accounting for 29.26% of the decline of the molecular species. Overall, the refining process had little effect on the fatty acid profile and distribution of TG molecular species in fish oil. [ABSTRACT FROM AUTHOR]

Freshwater fish are usually unpopular with people, mainly because of their unappealing earthy and fishy smell. Comprehensive two-dimensional gas chromatography is a relatively new analytical technique. Finally, different parts (the dorsal meat, belly meat, dark meat, skin, intestines, and gills) were investigated by comprehensive two-dimensional gas chromatography coupled with time-of-flight mass spectrometry (GC×GC-TOFMS) to explore their characteristic volatile components. In this study, a total of 49, 48, 61, 70, 73, and 65 volatile components were isolated in these six groups of samples, respectively, by GC×GC-TOFMS. Of these, 6, 7, 10, 13, 11, and 11 characteristic (ROAV ≥ 1) volatile compounds were identified in this study, including: Hexanal, Octanal, Nonanal, Heptanal, Decanal, 1-Heptanol, 1-Octen-3-ol, 2,4-Decadienal and (E,E)-2,4-Nonadienal, the majority of which were aldehydes and alcohols. The intensity range of fishy smells were identified, from strongest to weakest, as follows: gills, intestines, skin, dark meat, and belly/dorsal meat. [ABSTRACT FROM AUTHOR]