Formation of heterocyclic amines in fried fish fiber during processing and storage

The formation of heterocyclic amines (HAs) in fried fish fiber during processing and storage was studied. Fried fish fiber was prepared by boiling of raw fish, followed by eviscerating, pressing, chopping, and then the fish meat was subjected to frying, during which the various additives such as sugar, soybean sauce, and edible oil were added. The various HAs in fried fish fiber were analyzed by high-performance liquid chromatography with photodiode-array detection. Only four HAs, Norharman, Harman, 2-amino-9H-pyrido[2,3-b]indole, and 2-amino-3-methyl-9H-pyrido[2,3-b]indole were detected in fried fish fiber. The amount of HAs increased with increasing frying temperature. Amino acids might play a more important role for HA formation than reducing sugar during processing of fried fish fiber. During storage, the HAs increased with increasing storage temperature when the fried fish fiber was packed in an aluminum foil bag. However, the relationship between storage temperature and HAs formation was not consistent when the fried fish fiber was packed in a plastic bag.     

A micromachined chip-based electrospray source for mass spectrometry

A micromachining process is described for fabricating a mass spectrometry electrospray source on a silicon chip. The process utilizes polymer (parylene) layers to form a system of chambers, filters, channels, and hollow needle structures (electrospray emitters) that extend more than a millimeter beyond the edge of the silicon substrate. The use of photoresist as the sacrificial layer facilitates the creation of long channels. Access to the channel structures on the chip is through a port etched through the silicon substrate that also serves as a sample reservoir. A reusable chip holder consisting of two plastic plates and an elastomer gasket provides the means to mount the chip in front of the mass spectrometer inlet and make electrical and gas connections. The electrospray emitters have tapered tips with 5 microns x 10 microns rectangular openings. The shape of the tip can be varied depending on the shape of the mask used to protect the parylene structures during the final plasma etch. The parylene emitters are physically robust and require only a high electric field to achieve stable electrospray operation over a period of a few hours. Direct comparisons with conventional glass or fused silica emitters indicated very similar performance with respect to signal strength and stability, spectral quality, and endurance. The automated MS/MS analysis of a mixture of tryptic peptides was no more difficult and yielded nearly identical results as the analysis of the same sample using a conventional nanospray device. This work demonstrates that an efficient electrospray interface to mass spectrometry can be integrated with other on-chip structures and mass-produced using a batch process.     

层次分析法在风电场运行经济性评价中的应用

由于风电场运行管理的特殊性,任何单一的评价指标都难以对风电场运行经济性进行全面、完整、综合且客观的反映。提出运用层次分析法评价风电场运行的经济性,对风电场的发电情况、无功耗用、运行费用及人员效率等几个风电场运行经济性评价应考查的主要方面进行综合评价,以期对风电场运行经济性量化分析与评价有所启示。     

Diluted magnetic semiconductor properties of Zn1 − x Cox O: 1 at% Al thin films prepared by pulsed DC magnetron sputtering

Zn_{1 − x} Co_xO: 1 at% Al(x = 0−0.3) films were grown on corning 7059 glass by asymmetrical bipolar pulsed dc magnetron sputtering. The c-axis orientation along the (002) plane was enhanced with increasing Co concentration. The ZnCoO thin films are grown to the fibrous grains of tight dome shape. The transmittance spectra showed that sp-d exchange interactions and typical d-d transitions become activated with increasing Co concentration. The electrical resistivity of ZnCoO films increased ranging from ∼10^{− 3} to ∼10⁻² Ω ⋅ cm with increasing Co concentration, especially it increased greatly at 30 at% Co. X-ray photoelectron spectroscopy and alternating gradient magnetometer analyses indicated that no Co metal cluster in the ZnCoO films is formed and room temperature ferromagnetism is exhibited. These electrical and magnetic properties of ZnCoO films suggest a potential application of dilute magnetic semiconductor devices.     

Magnetic properties of nanostructural γ-Ni-28Fe alloy

Nanostructural γ-Ni-28Fe alloy (nano γ-Ni-28Fe) was successfully prepared by mechanochemical alloying(MCA). The relationship between the microstructure and the synthesis conditions was investigated by using XRD, TEM, SEM as well as BET analyzer. The results show that nano γ-Ni-28Fe alloy is composed of a gamma phase (FCC structure). Its grain size is about 20 nm at reduction temperature below 600 °C. The magnetic measurements indicate that the saturation magnetization of nano γ-Ni-28Fe alloy is 102.4 A·m²/kg, and the coercivity is much higher than that of conventional coarse-grained counterpart. The result may be attributed to its decrease of the grain size and chemical composition in nano γ-Ni-28Fe alloy.     

Analysis of multi‐year drought and high inflow events into the eildon storage

This article presents information from an analysis of the multi‐year drought and high flow durations obtained from a historical time series (1891–1989) of annual inflows aggregated from all streams and rivers flowing into the Eildon Storage, a major storage for irrigation water in Northern Victoria, South‐East Australia. The drought and high inflow duration sequences are found to be affected by the fluctuating climatic cycle, called the Southern Oscillation. The multi‐year drought and high inflow duration sequences are analysed first through a model with IID observations in the annual runoff and second, through a first order auto‐regressive Markov model with a two‐state Markov chain with time homogeneous transition assumption. An alternative approach is taken to estimate the termination rate of multi‐year drought and high inflow duration sequences, based on frequency analysis and the basic concepts of reliability theory. This approach confirms the initial findings.     

Variable sensitivity photodetector for optical neural networks

A novel type of photodetector called a variable sensitivity photodetector (VSPD) has been developed for an optical implementation of a neural network. The function of the VSPD is a photodetector with functions of both a spatial light modulator and a photodetector. The VSPD with a metal-semiconductor-metal structure is shown to be suitable for the implementation of the analog synaptic weight with a bipolar value. A two-dimensional 8×8 array of VSPDs was fabricated on a GaAs substrate and integrated with a light-emitting-diode array with eight lines in hybrid form. This chip can simulate an eight-neuron system with 64 variable synaptic connections. The application to pattern classification was demonstrated by using the chip. The chip was used to classify 12 patterns into three categories by the backpropagation learning algorithm in a three-layered network. The authors studied how the nonlinear and nonuniform characteristics of the VSPD array device affect the learning performance     

From the Historian-another matter of history [scalar product]

The basic incorrectness of the scalar product approach to deriving the differential expression for the divergence of a vector function in the Cartesian system is demonstrated. The origin of the approach is traced, and its ubiquity in the literature is documented     

Einfluß mechanischer Belastungen auf das Kavitationsverhalten metallischer Werkstoffe

Kritische Literaturauswertung. Kavitationsanlage für überlagerte mechanische Spannungen. Ergebnisse für die Werkstoffe technisch reines Eisen, St42-2 und G-X6 CrNiMo 1810 (1.4408). Einführung einer neuen Meßgröße zur Beschreibung des Kavitationsverhaltens sowie des additiven Spannungseinflusses. Beschreibung der ?Kavitations“-Fließgrenze. Diskussion und mathematische Formulierung der Ergebnisse.     

Algorithms for the Determination of Cutsets in a Hypergraph

Given a hypergraph,this paper provides three algorithms for finding all its minimal cutsets,minimal link cutsets and the least cutsets.The result not only set up a new studying field on cutsets of hypergraph,but also lay a foundation of analyzing the performance of multibus systems.The algorithm for determining all the least cutsets in a hypergaph is polynomial complex and more efficient than that in [2].