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81.
82.
Quantitative phase imaging(QPI)with its high-contrast images of optical phase delay(OPD)maps is often used for label-free single-cell analysis.Contrary to other imaging methods,sensitivity improvement has not been intensively explored because conventional QPI is sensitive enough to observe the surface roughness of a substrate that restricts the minimum measurable OPD.However,emerging QPI techniques that utilize,for example,differential image analysis of consecutive temporal frames,such as mid-infrared photothermal QPI,mitigate the minimum OPD limit by decoupling the static OPD contribution and allow measurement of much smaller OPDs.Here,we propose and demonstrate supersensitive QPI with an expanded dynamic range.It is enabled by adaptive dynamic range shift through a combination of wavefront shaping and dark-field QPI techniques.As a proof-of-concept demonstration,we show dynamic range expansion(sensitivity improvement)of QPI by a factor of 6.6 and its utility in improving the sensitivity of mid-infrared photothermal QPI.This technique can also be applied for wide-field scattering imaging of dynamically changing nanoscale objects inside and outside a biological cell without losing global cellular morphological image information.  相似文献   
83.
Bacterial alkaline phosphatase (BAP) was site-specifically and covalently immobilized on magnetic particles (MPs) using the enzymatic reaction of microbial transglutaminase (MTG). Immobilization efficiency was affected by the chemical surface treatment of MPs and immobilized BAP exhibited more than 90% of the initial activity after 10 rounds of recycling.  相似文献   
84.
To simplify the labor-intensive conventional routine testing of samples to detect Leuconostoc at a meat processing plant, we developed polymerase chain reaction (PCR) primers specific for Leuconostoc from 16S rRNA gene sequences. These primers did not detect other common lactic acid bacteria such as Lactobacillus plantarum, Lact. sake, Lact. fermentum, Lact. acidophilus and Weissella viridescens. PCR with this primer detected all Leuconostoc species tested (Leu. mesenteroides subsp. mesenteroides, Leu. pseudomesenteroides, Leu. carnosum, Leu. lactic, Leu. citreum, Leu. amelibiosum, Leu. gelidum), except for Leu. fallax, and no other lactic acid bacteria on agarose gel electrophoresis. The method could identify areas contaminated with Leuconostoc in a large-scale industrial meat processing plant. Of 69 samples analyzed, 34 were positive for Leuconostoc according to the conventional culture method (isolation of LAB producing dextran) and PCR, whereas 29 were negative according to both. Six samples were culture-negative but positive by PCR. No false negative results were generated by PCR. The method is rapid and simple, is useful for routinely monitoring areas contaminated with Leuconostoc in meat processing plants, and could help to prevent the spoilage of meat products.  相似文献   
85.
An analytical method for the determination of ethyl carbamate in alcoholic beverages has been developed and optimized. A combination of headspace solid phase microextraction (HS‐SPME), as the extraction technique, and GC/MS, as the determination technique, was utilized. Analytical grade ethyl carbamate dissolved in ethanol solution was analyzed to determine the optimum analytical conditions. Ethyl carbamate‐d5 was added as an internal standard. The following HS‐SPME conditions were investigated: type of stationary phase of the fibre, ethanol content, sample volume and extraction time. The optimized procedure showed that the detection limit, relative standard deviation, and recovery were 6.7 μg/L, 0.4–2.0%, and 103.6–107.6%, respectively. The precision of this new method was equivalent to previous analyses. Finally, the developed method was applied to the analysis of ethyl carbamate in sake.  相似文献   
86.
Water-repellent particles were prepared by spraying polytetrafluoroethylene (PTFE) on activated carbon. Gas-liquid volumetric mass transfer coefficient and holdup were determined in gas-liquid cocurrent upflow and downflow packed beds from the measurements of gas desorption and volume, respectively. As the PTFE loading increased, the gas-liquid volumetric mass transfer coefficients in both upflow and downflow modes were enhanced. Gas holdup in the upflow mode increased with the PTFE loading, while the dynamic liquid holdup in the downflow mode decreased. The enhancement of the mass transfer rate from gas to liquid can be explained by the effect of water-repellency on the surface of activated carbon.  相似文献   
87.
Active oxidation behavior of CVD-SiC in CO─CO2 atmospheres was investigated using a thermogravimetric technique in the temperature range between 1823 and 1923 K. The gas pressure ratio, P CO2/ P CO, was controlled between 10−4 and 10−1 at 0.1 MPa. Active oxidation rates (mass loss rates) showed maxima at a certain value of P CO2/ P CO, ( P CO2/ P CO )*, In a P CO2/ P CO region lower than the ( P CO2/ P CO)* a carbon layer was formed on the SiC surface. In a P CO2/ P CO region higher than the ( P CO2/ P CO)*, silica particles or a porous silica layer was observed on the SiC surface.  相似文献   
88.
Z‐isomers of lycopene exhibit higher bioavailability and antioxidant capacity than those of the all‐E‐isomer. Therefore, it is important to develop an efficient and environmentally friendly procedure for Z‐isomerization. The current methods for Z‐isomerization of (all‐E)‐lycopene use toxic chemicals such as organic solvents and catalysts. This study is aimed to develop a chemical‐free method for Z‐isomerization of (all‐E)‐lycopene in tomato powder by hot air and superheated steam heating. The Z‐isomerization reaction is promoted by heating above the melting point of lycopene. When heated with superheated steam, the thermal decomposition of lycopene is suppressed compared to that when heated with hot air. When tomato powder is heated at 240 °C for 5 min by superheated steam, the total Z‐isomer content and remaining lycopene are 69.0% and 90.7%, respectively, while with hot air heating, the total Z‐isomer content and remaining lycopene are 69.9% and 68.0%, respectively. These results indicate that the thermal Z‐isomerization of lycopene occurs in the molten state and heating in a low oxygen atmosphere suppresses the thermal decomposition of lycopene. Practical Applications: Tomato powder rich in lycopene Z‐isomers is an important ingredient for the food and animal feed industries. Since Z‐isomers of lycopene are more soluble in solvents including ethanol which is a low‐toxicity and environmentally friendly solvent, the efficiency of lycopene extraction with ethanol can be improved by using the Z‐isomer‐rich tomato powder as a raw material. The obtained Z‐isomer‐rich extract has a high added value because the Z‐isomers have higher bioavailability and antioxidant capacity than those of the all‐E‐isomer. In addition, since lycopene Z‐isomers exhibit higher accumulation efficiency and better color improvement in hen egg yolks than those of the all‐E‐isomer, Z‐isomer‐rich tomato powder is an effective animal feed.  相似文献   
89.
This paper describes the successful test operation of a 50 t/h concentrate feed rate (or on the anode copper basis 9000 tlm) with the Mitsubishi Process. Particular emphasis is given to the analyses of the furnace capacity by the measurement of flow pattern and oxygen potential. Smelting rate on the unit hearth area of the smelting furnace is now one-ton of concentrate/m2·h. The results of the analyses show the further potential of the furnace capacity of the process.  相似文献   
90.
The aroma characteristics and volatile profiles of 14 carrot varieties were investigated by sensory evaluations and gas chromatography–mass spectrometry volatile analyses. The sensory map obtained by principal components analysis showed that the sensory attributes comprised 3 categories: sour/green, overall carrot/harsh/ink‐like, and fruity/fresh/sweet. The Kuroda type is characterized by lower intensities of overall carrot/harsh/ink‐like and fruity/fresh/sweet notes. Furthermore, volatile profiling indicated that this type did not have significantly higher amounts of volatiles. Partial least squares regression analysis determined the quantitative contributions to ink‐like, harsh, and fruity carrot aromas; monoterpenes had significant positive correlations with these attributes, while bisabolene isomers had negative correlations. The aroma attribute intensity and contents of volatiles and nutritional compounds are relatively low in the Kuroda type than in other carrot types. This type may be useful for reducing carrot harshness during the development of new carrots with good eating qualities.  相似文献   
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