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ABS T R A C T We evaluated the effects of different oxidation levels of lipids on protein degradation and biogenic amines (BAs) formation during Sichuan-style sausages processing. Lipids with varying degrees of oxidation were obtained through storage at different temperatures and added as raw materials of Sichuan-style sausages, followed by the analyses of lipid oxidation, protein degradation, biogenic amine content, and other indicators. During the pro-cessing, with increasing degree of lipid oxidation, the contents of peroxide value (POV), thiobarbituric acid reactive substances (TBARs), protein degradation index (PI), amino acid nitrogen (AAN), free amino acids (FAAs), and BAs increased. Based on the protein electrophoresis results, the higher the oxidation degree of pig backfat, the higher degree of sarcoplasmic protein oxidation, and the greater myofibril protein degradation. Pearson correlation revealed that lipid oxidation, protein degradation, and BAs content correlated significantly (P < 0.05).

Aim: To evaluate intravenously injected bovine serum albumin-templated gold nanoparticles (BSA-GNPs) for radiosensitization effects on H22 hepatoma-bearing mice. Materials & methods: BSA-GNPs in different size were injected intravenously with a dose of 4 mg Au/kg. After 30 min injection, the tumor-bearing mice were irradiated with 5 Gy x-ray. Results: BSA-GNPs in 8, 50 and 187 nm were synthesized and have no obvious cytotoxicity to HeLa, HepG2 and HeCat cells when the concentration was up to 32 μM. And no obvious physiological injury of mice occurred when the intravenous injection dose was 4 mg Au/kg. In vivo study indicates 8 and 50 nm BSA-GNPs can inhibit tumor growth through inducing apoptosis in radiotherapy, with enhancement factors 1.93 and 2.02, respectively. Conclusion: BSA-GNPs in 8 and 50 nm are promising radiosensitizers in radiotherapy of subcutaneously transplanted hepatocarcinoma.

To make up the gap of wasted phosphonates being too much as pollutants and phosphorus being too little as a natural resource, electrochemical “oxidation-precipitation” system was rationally developed to recover phosphorus with simultaneous mineralization of ethylenediamine tetra(methylene phosphonic acid) (EDTMP), a typical phosphonate. In this process, BDD( OH) was the primary oxidative species for EDTMP degradation, which led to the bond cleavage in the sequence of C-N, C-P and C-C. Increasing current density from 3 to 30 mA cm−2 improved the mineralization efficiency of EDTMP from 14% to 72% within 120 min, accompanying 65–95% of EDTMP conversion to orth-P. With the presence of 50 mg L−1 Ca2+, 21–83% of phosphorus was recovered as insoluble calcium phosphate at the cathode surface. High initial Ca2+ concentration favored the phosphorus recovery, whereas it was negatively influenced with the presence of Mg2+ and HCO3–. In addition, phosphorus recovery was negligibly affected by solution pH in the range of 3.0 to 12.0 because the locally alkaline condition was well maintained at the cathode surface. Phosphorus was electrochemically recovered mainly in the form of thermodynamically most stable hydroxyapatite, which proceeded via the formation of brushite, octacalcium phosphate, and amorphous calcium phosphate with Δ[Ca]/Δ[P] molar ratio increasing from 1.0 to 1.67. Based on the results of phosphorus recovery from the real wastewater, we envision that this synchronous anodic oxidation-cathodic precipitation process can be applied as an environmentally compatible and feasible strategy for phosphorus recovery from the phosphonate wastewaters.

Despite the fact that electron-trapped oxygen vacancy and [0 0 1] facets fundamentally affect the reactivity of TiO2, their synergistic role in the electrochemical activity of TiO2 toward p-nitrophenol (p-NP) reduction is still unknown. In this study, defective and [0 0 1] facets engineered TiO2 cathode, i.e. Ti/TiO2−x-0 0 1, was prepared for p-NP reduction. In comparison to defective Ti/TiO2 cathode with [1 0 1] facets (Ti/TiO2−x-1 0 1), the combination of the electron-trapped oxygen vacancy and [0 0 1] facets exhibited a synergistic effect to improve the electrochemical reduction efficiency of TiO2. Density functional theory calculations verified that the introduction of [0 0 1] facets and electron-trapped oxygen vacancy on TiO2 was beneficial to facilitate electron transfer and improve the indirect reduction efficiency for p-NP electrochemical reduction. Moreover, the electron-trapped oxygen vacancy extent of Ti/TiO2−x-0 0 1 was modulated by adjusting reduction temperature (250–650 °C). The maximum electron-trapped oxygen vacancy amount of Ti/TiO2−x-0 0 1 was attained at the reduction temperature of 350 °C, which resulted in the highest p-NP reduction efficiency of 99.3%, accompanying the p-AP selectivity of 89.5%. In this case, the abundant active and adsorption sites were provided on the surface of Ti/TiO2−x-0 0 1 prepared at 350 °C, in which p-NP adsorption coefficient and electrochemical surface area increased to 1.01 L mg−1 and 25 cm2, respectively. Generally, this work provides a paradigm for the design of efficient non-metallic catalyst for nitroaromatic chemicals reduction.

Velocity of Debris flow in drainage canal is an important parameter in designing. In order to explore the flow law of Debris flow, Real debris flow model experiments were carried out indoors to explore the energy flow velocity and dissipation of different Debris flow density, threshold of spacing, drainage canal slope Debris flow. Then get the following conclusions: Under the experimental conditions, the debris flow velocity showed a gradual decreasing trend; Debris flow average flow velocity decreases with increasing density of Debris flow; Debris flow average flow velocity increases with slope; Debris flow velocity increases with the increases of the rib spacing. Tank energy dissipation rate showed the following rules: Average energy dissipation of single rib rate increase with the density of Debris flow and increase with the drainage canal slope increases. Under different the rib spacing, overall energy dissipation rate increases with the the rib spacing is reduced, but average energy dissipation of single rib rate increases with increases the distance between two ribs.

Drainage canals are engineering structures widely used for debris flow mitigation. When passing through a drainage canal, debris flow usually scours the gully bed at the back of the rib sill of the drainage canal, which leads to failure of the rib sill. Therefore, the scour depth at the back of the rib sill is an important design problem and it is related to the economic benefits of engineering and service years. To explore the law of the depth of the scour pit after debris flow through drainage canal ribs, we first proposed a formula for the calculation of the maximum scour depth at the back of a rib sill based on energy conservation. We then conducted a series of simulation experiments to test the proposed formula. The experimental results show that the scour depth, trench slope and the distance between ribs all increase with a decrease in debris flow density. We then compared the results of experiments and formula calculations. Through the testing analysis, we found that the calculation results of the conducted formula correspond with the experimental results better. Finally, taking Qipan Gully as an example, we designed the ultimate depth of a drainage canal for debris flow using the calculation formula.

Due to a variety of outstanding properties, such as large surface area, high length-to-diameter ratio, flexible surface functionality, tunable surface morphologies and superior mechanical performance, electrospun ultrathin fibers are suitable for flexible and stretchable devices, which have aroused much attention nowadays. In this review, we aim to summarize recent developments in the fabrication of flexible/stretchable electronic devices via electrospinning, including strain and pressure sensors, supercapacitors, organic field-effect transistors, and transparent electrodes, which are the key components of flexible/stretchable devices. Moreover, in order to further improve the performance of these devices, some challenges facing electrospun fibers (e.g. production on large scale, precise deposition and flexibility improvement of electrospun inorganic fibers) and subsequent integration for flexible/stretchable electronic devices have also been discussed.

Uniaxially aligned and cross-aligned arrays of ultrafine polymer fibers have been fabricated by a novel and effective centrifugal electrospinning setup with rotating polymer solution jets. Comparing with conventional electrospinning (10–30 kV) and centrifugal spinning (4,000–12,000 rpm), this technique only requires a lower working voltage (2.8–6.0 kV), a slower rotational speed (360–540 rpm), and a shorter spinning distance (2.0–4.0 cm). In addition, the influences of experimental parameters such as working voltage, rotational speed, collecting distance, and solution concentration on the alignment of the as-spun fibers are investigated using image analysis techniques. It is found that the working voltage and rotational speed mainly influence the perpendicular and linear velocities of the fibers, respectively. The polymer fibers tend to show higher alignment degree when these two velocities are very close. Optimum conditions (working voltage 3.0 kV, rotational speed 420 rpm, collecting distance 2.5 cm, and solution concentration 18 wt%) to maximize alignment degree (~97%) of polystyrene fibers are also obtained.

The collagenase, produced extracellular by Bacillus pumilus Col-J, was purified by ammonium sulfate precipitation followed by two gel filtrations, involving Sephadex G-100 column and Sepharose Fast Flow column. Purified collagenase has a 31.53-fold increase in specific activity of 87.33 U/mg and 7.00% recovery. The collagenase has a relative molecular weight of 58.64 kDa by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The optimal temperature for the enzyme reaction was 45 °C. More than 50% of the original activity still remained after 5 min of incubation at 70 °C or 10 min at 60 °C. The maximal enzyme activity of collagenase was obtained at pH 7.5, and it was stable over a pH range of 6.5–8.0. The collagenase activity was strongly inhibited by Mn2+, Pb2+, ethylenediamine tetraacetic acid, ethylene glycol tetraacetic acid, and β-mercaptoethanol. However, Ca2+ and Mg2+ greatly increased its activity. The collagenase from B. pumilus Col-J showed highly specific activity towards the native collagen from calf skin. The K m and V max of the enzyme for collagen were 0.79 mg/mL and 129.5 U, respectively.

Rapid hemostasis of solitary organs is still a big challenge in surgical procedures or after major trauma in both civilians and on the battlefield. Here, we report the first use of an airflow-directed in situ electrospinning method to precisely and homogeneously deposit a medical glue of n-octyl-2-cyanoacrylate (OCA) ultrathin fibers onto a wound surface to realize rapid hemostasis in dozens of seconds. In vivo and in vitro experiments on pig liver resection demonstrate that the self-assembled electrospun OCA membrane with high strength, good flexibility and integrity is very compact and no fluid seeping is observed even under a pressure of 147 mm Hg. A similar effect has been achieved in an in vivo experiment on pig lung resection. The results provide a very promising alternative for rapid hemostasis of solitary organs as well as other traumas, providing evidence that the postoperative drainage tube may not be always necessary for surgery in the near future.

Stretchable strain sensors based on aligned microfibrous arrays of poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate)-poly(vinyl pyrrolidone) (PEDOT:PSS-PVP) with curled architectures have been fabricated by a novel reciprocating-type electrospinning setup with a spinneret in straightforward simple harmonic motion. The incorporation of PEDOT:PSS into PVP is confirmed by Raman spectra, which improves the room-temperature conductivity of the composite fibers (1.6 × 10(-5) S cm(-1)). Owing to the curled architectures of the as-spun fibrous polymer arrays, the sensors can be stretched reversibly with a linear elastic response to strain up to 4%, which is three times higher than that from electrospun nonwoven mats. In addition, the stretchable strain sensor with a high repeatability and durability has a gauge factor of about 360. These results may be helpful for the fabrication of stretchable devices which have potential applications in some fields such as soft robotics, elastic semiconductors, and elastic solar cells.

The pumped-storage station advances efficiently the safety and reliability of power grid. But the traditional management mode is not suitable for the requirement of the pumped-storage station because of the lack of mature power market, lower peak-valley price variance and the difficulty of aux service entering the market. By analysis on the management characters of the pumped-storage station, a mode of capacity distribution based on quota system is put forward. The mode has been tested by the Shandong pumped storage station and the reasonability and feasibility have also been proved.

Ultrathin indium oxide (In2O3) hollow fibers were successfully fabricated by electrospinning poly(vinylidene fluoride) (PVDF) nanofibers, magnetron sputtering of In2O3 on PVDF fibers followed by calcination of In2O3/PVDF composite fibers. The hollow In2O3 fibers were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), x-ray diffraction (XRD) and UV-Visible spectroscopy. The outer diameter of the hollow fibers was in the range of 700–900 nm, and the inner diameter was about 400–600 nm. The optoelectronic properties of the In2O3 fibers were investigated by the irradiation of UV light with different wavelengths (254, 308 and 365 nm). It was found that the In2O3 hollow nanofibers had a fast and strong response to UV irradiation. The response time was less than 10 s, and the sensitivity (~102) decreased with the UV light wavelength increasing or the light intensity decreasing.

Background: The purpose of this study was to compare the diagnostic accuracy of small nodules in the chest by using different compression methods. Method: Two radiologists with 5 years experience twice interpreted 39 chest images by using lossless and lossy compression methods. The time interval was 3 weeks. Each time the radiologists interpreted one kind of compressed images. The image browser used the Unisight software provided by Atlastiger Company in Shanghai. The interpreting results were analyzed by the ROCKIT software and the ROC curves were painted by Excel 2002. Results: In studies of receiver operating characteristics for scoring the presence or absence of nodules, the images with lossy compression method showed no statistical difference as compared with the images with lossless compression method. Conclusion: The diagnostic accuracy of chest nodules by using the lossless and lossy compression methods had no significant difference, we could use the lossy compression method to transmit and archive the chest images with nodules.

In this paper we introduce wall-climbing robots of two different absorption schemes: one with single suction cup and the other with permanent magnetic crawlers. The former adopts an omnidirectional vehicle and can perform remote-control inspection of nuclear storage tanks. Moreover, it is further developed for cleaning both the ceramic tile and glass surfaces of high-rise buildings. The latter consists of two types of robots: one is for maintenance automation of storage tanks in petrochemical enterprises, which can perform operations of sand-blasting, spray-painting and inspection; and the other is for monitoring the boiler wall water tubing.

Ce-doped p-type ZnO nanofibers were synthesized by electrospinning and followed calcinations. The surface morphology, elementary composition, and crystal structure of the nanofibers were investigated. The field effect curve confirms that the resultant Ce-doped ZnO nanofibers are p-type semiconductor. A p-n heterojunction device consisting of Ce-doped p-type ZnO nanofibers and n-type indium tin oxide (ITO) thin film was fabricated on a piece of quartz substrate. The current-voltage (I-V) characteristic of the p-n heterojunction device shows typical rectifying diode behavior. The turn-on voltage appears at about 7 V under the forward bias and the reverse current is impassable.

Solvent recovery is a big challenge for industrial-level production of ultrathin fibers by solution electrospinning because more than 70 wt% of the precursor solution is volatilizable organic solvent. In this paper, we report an interesting solventless electrospinning technique for the fabrication of poly(ethyl-2-cyanoacrylate)/polymethylmethacrylate (PECA/PMMA) fibers. The spinning solution only contains two components: ethyl-2-cyanoacrylate (ECA) monomer and PMMA, which are nearly all (>90%) electrospun into fibers at room temperature. The fiber solidification mechanism during the electrospinning process could be ascribed to the rapid polymerization of the ECA monomer in the presence of water vapour (specifically hydroxide ions) in the atmosphere, which is quite different from the conventional solvent evaporation in solution electrospinning or the fiber cooling mechanism in melt electrospinning. In addition, the morphology, structure, and influence of temperature and PMMA concentration have also been studied. The results may give some stimulation for developing new ecofriendly electrospinning methods.