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关键词： Drinking water   Natural radioactivity   Annual effective dose   Gamma-ray spectrometry  

摘要： In this study, the average activity concentrations of Ra-226, Ra-228 and K-40 in drinking waters (tap and bottled) consumed in Kastamonu province of Turkey were found as 0.7, 0.5 and 1.3 Bq L-1, respectively. The average value of pH, conductivity, total dissolved solids and total hardness of waters were found as 7.5, 217 mu S cm(-1), 142 mg L-1 and 154 mg L-1 for tap waters and 7.4, 94 mu S cm(-1), 61 mg L-1 and 58 mg L-1 for bottled waters. The average activity concentration of Ra-228 in drinking waters was higher than the WHO recommended concentration of 0.1 Bq L-1.

关键词： Purple turnip dietary fiber   Modification   Structural analysis   Microrheological properties   Physicochemical properties  

摘要： Insoluble dietary fiber (IDF) and soluble dietary fiber (SDF) were extracted from purple turnip (Brassica rapa L.). IDF was modified with alkaline hydrogen peroxide (AHP) or enzymatic hydrolysis (EH) to obtain modified IDF (A-IDF and E-IDF) and modified SDF (A-SDF and E-SDF). The composition and physicochemical properties of the samples were investigated using FT-IR, XRD, SEM, and DSC. Both modification methods improved the hydration properties, microrheological properties, and in vitro cholesterol adsorption capacities (CACs) of the samples. Specifically, AHP greatly improved the water retention capacity (WRC), water swelling property (WSC) and oil holding capacity (OHC) of the IDF. The effects of EH on the yield, WRC, OHC and CAC of the SDF were more significant than those of EH on IDF properties. Principal component analysis (PCA), clustering heatmap and correlation heatmap revealed that a significant negative correlation was found between OHC, CAC and particle size, and pectin content presented a positive correlation with crystallinity. In summary, EH was considered to be the ideal modification method to enhance the functional characteristics of dietary fiber from purple turnip, and E-SDF showed better application potential than A-SDF.

关键词： Optical and Electronic Materials   Characterization and Evaluation of Materials  

摘要： Optical high-quality semi-organic piperazinium tetrachlorozincate monohydrate, [C4H12N2] ZnCl4 center dot H2O (PTCZ), single crystals were grown by conventional solution method. The structure of grown crystal was confirmed by the single-crystal X-ray diffraction (SXRD) analysis. The material phase purities and its various (hkl) planes have been confirmed by the powder X-ray diffraction (PXRD) analysis at room temperature. The different functional groups were confirmed by the Fourier transform infrared (FTIR) spectroscopy. The optical quality of the PTCZ single crystal and band gap energy have been identified by the UV-Vis-NIR spectral analysis and also calculated refractive index of the material. The thermal stability of the PTCZ single crystal was investigated by TG-DTA. The hardness-related properties were analyzed by microhardness tester. The dielectric properties have been measured on the grown single crystal and the electronic polarizability value has been calculated with various theoretical approaches. The etching was carried out on the grown crystal to find the dislocation density. The crystal atomic perfection has been investigated by the high-resolution X-ray diffraction (HRXRD) or Rocking curve (RC) analysis. The Z-scan measurement has been carried out to find third-order optical susceptibility (chi((3))) of the grown single crystal using solid-state laser (640 nm).

关键词： High hydrostatic pressure   Leaf mustard kimchi   Refrigerated storage   Supercooling  

摘要： Kimchi products have a short shelf life due to continuous bacterial growth and fermentation. Herein, the microbiological and physicochemical properties of leaf mustard (Brassica juncea L.) kimchi were evaluated after high hydrostatic pressure (HHP) treatment (400 and 600 MPa for 5 min) and storage under supercooling ( 4.5 degrees C) or refrigeration (4 and 8 degrees C) conditions. Moreover, predictive models describing the growth kinetics of total lactic acid bacteria (TLAB) in leaf mustard kimchi were constructed. Treatment with 600 MPa reduced the total LAB and coliform counts in the samples before storage to 1.30 and > 1 log CFU/g, respectively. Supercooling storage prevented microbial growth for 30 days and allowed the maintenance of the titratable acidity, reducing sugar content, instrumental colour, total phenolic content, and antioxidant capacity of the samples. The Logistic and Gompertz models were relatively more acceptable to predict the growth behaviour of TLAB in leaf mustard kimchi treated/non-treated with 400 MPa during supercooled or refrigerated storage. Altogether, these findings suggest that HHP treatment combined with supercooling storage conditions that delay O-2 and CO2 concentration changes in packaged kimchi's headspace could help maintain the initial microbiological and physicochemical qualities of leaf mustard kimchi.

关键词： 物理化学  

ISBN: (纸本)9787305245657

摘要： 本书主要内容为化学热力学、电化学、化学反应动力学、表面现象与胶体化学、结构化学等五个方面的各种实验项目，以及实验仪器及技术，包括实验技术，由实验基础知识、实验仪器使用方法、实验技能等组成，如热学与温度测试技术、压力测试技术、电化学测试技术、光学测试技术、结构化学测试与分子模拟技术等。此外，本书还配二维码数字化资源。

关键词： Germination   Quinoa starch   Structure   Physicochemical properties  

摘要： Changes in the structural and physicochemical properties of quinoa starch during germination were investigated. The amylose content of Zhongli No.1 quinoa (ZQ) was 17.37%, which was almost 4-5 times greater than the other two genotypes. The surface of germinated quinoa starch granules showed more pinholes and obvious crimples than native starch. The germinated Mengli No. 1 quinoa starch (MQS) and Yunnan red quinoa starch (YQS) had a higher ratio of short chains than native starch, while the opposite result was observed in Zhongli No.1 quinoa starch (ZQS). Germination decreased the relative crystallinity of starch, but it did not change its crystalline structure type. Peak viscosity, trough viscosity, retrogradation enthalpy and the percentage of retrogradation significantly decreased during germination. In conclusion, germination significantly impacted on the structural and physicochemical properties of quinoa starch, which provides a basis for the utilization of germinated quinoa products in the food industry.

关键词： Biolubricants   Cloud point   Pour point depressant   Kinematic viscosity   Pour point   Viscosity index improver  

摘要： Previously synthesized C36-dimer acids (DA) have been esterified (97 +/- 0.2% conversion at 120 degrees C for 72 hours) with 2-ethylhexanol (2-EH) to produce a new class of C52-DA 2-EH esters that have potential application in biolubricant formulations such as base oils and additives. Investigation of physicochemical and lubricant properties showed the bio-based esters have good solubility in commercial base stocks such as polyalpha olefin (PAO-6) (>20 w/w) and high-oleic sunflower oil (HOSuO) (>20 w/w). The neat C52-DA 2-EH esters displayed a three- to eightfold higher kinematic viscosity and comparable viscosity index (VI = 134) as a commercial base stock, PAO-6 (VI =137). Both C52-DA 2-EH esters, whose parent C36-DA were synthesized with two different zeolite catalysts, were oxidatively stable above 176 degrees C. Blending C52-DA 2-EH esters in HOSuO improved the pour point (PP) of HOSuO from -18.8 to -21.0 degrees C at 1% w/w and the cloud point (CP) from -6.3 to -10.6 degrees C at 8% w/w of C52-DA 2-EH ester 1. A similar trend was observed for C52-DA 2-EH ester 2, indicating that the esters possess PP depressant (PPD) characteristics in HOSuO blends. Blending C52-DA 2-EH esters in PAO-6 increased the VI of PAO-6, which is an indication that the bio-based esters were acting as VI improvers (VII). It was concluded that C52-DA 2-EH esters can be employed commercially as bio-based base oils and as PPD and VII additives in lubricant formulations.

关键词： Antioxidant activity   Barberry   Compressed tablet   Flowability   Powder  

摘要： Barberry fruit is a good source of natural antioxidants and various functional compounds. The barberry pulps throw away during producing barberry juice. The aim of the study was to develop the barberry pulp powder as an additive with nutritional value (antioxidant activity, total phenols, and flavonoids content) and quality properties (color properties, sensory properties, flowability). The heating drying was conducted at different conditions (50, 60, and 70 degrees C for 10, 13, and 16 h). In the second step, the best powder was used to develop compressed tablets of barberry powder with different concentrations (30-50%). The amount of antioxidant activity and flavonoid compounds of powders were in the range of 63.32-80.23% and 164.42-232.91 ppm, respectively. Drying increased the values of DPPH scavenging activity, total phenol and flavonoid content (p < 0.05). The Carr index (0.15-0.19), and Hausner ratio (1.22-1.25) determined the good flowability. According to the results, the optimal temperature and time for drying was 60 degrees C for 13 h. This sample was applied for tablet preparation. The tablets had a diameter of 5 mm and thickness of 3 mm and included 14.40-17.35%, 48.77-65.13%, and 70.09-98.33 mg GAE/100 g of fiber, antioxidant activity and, total phenol content, respectively.

关键词： Barnyard   Flour   Irradiation   Pasting   Antioxidant  

摘要： Wild barnyard grass grains were ground to flour and subjected to irradiation doses of 0, 2.5 and 5 kGy. The flour was studied for physicochemical, functional and antioxidant properties. Moisture, protein, fat and ash in untreated sample were 10.0 g/100 g, 11.09 g/100 g, 1.96 g/100 g and 0.75 g/100 g. Physicochemical properties of samples varied significantly (p < 0.05) upon irradiation as compared to unirradiated flour. Results revealed increase in solubility index (0.04?0.09 g/g) and light transmittance (1.79?2.92%) with decrease in swelling index (3.23?2.72 g/g) and syneresis (57.10?56.09 g/100 g) of flours upon irradiation. Pasting properties were found to decrease with irradiation. Functional properties like oil absorption capacity (4.90?5.15 g/g) and emulsion capacity (1.31?4.66%) increased significantly (p < 0.05) with irradiation. DPPH inhibition of treated flour increased from 1.68% to 14.67% at 5 kGy dose. Similarly, TPC and inhibition of lipid peroxidation of treated samples increased from 0.41 to 0.85 mg GAE/g and 32.9?43.81%, respectively.

关键词： Nanostructured lipid carriers   Magnetic nanoparticles   Chitosan   1   8-cineole   Cytotoxicity   Cancer cells  

摘要： The development of versatile carriers to deliver chemotherapeutic agents to specific targets with establishing drug release kinetics and minimum undesirable side effects is becoming a promising relevant tool in the medical field. Magnetic hybrid nanostructured lipid carriers (NLC) were prepared by incorporation of 1,8-cineole (CN, a monoterpene with antiproliferative properties) and maghemite nanoparticles (MNPs) into a hybrid matrix composed of myristyl myristate coated with chitosan. Hybrid NLC characterized by DLS and TEM confirmed the presence of positively charged spherical nanoparticles of around 250 nm diameter and +10.2 mV of Z-potential. CN encapsulation into the lipid core was greater than 75 % and effectively released in 24 h. Modification of the crystalline structure of nanoparticles after incorporation of CN and MNPs was observed by XRD, DSC, and TGA analyses. Superparamagnetic NLC behavior was verified by recording the magnetization using a vibrating scanning magnetometer. NLC resulted in more cytotoxic than free CN in HepG2 and A549 cell lines. Particularly, viability inhibition of HepG2 and A549 cells was increased from 35 % to 55 % and from 38 % to 61 %, respectively, when 8 mM CN was incorporated into the lipid NPs at 24 h. Green fluorescent-labeled NLC with DIOC18 showed an enhanced cellular uptake with chitosan-coated NLC. Besides, no cytotoxicity of the formulations in normal WI-38 cells was observed, suggesting that the developed hybrid NLC system is a safe and good potential candidate for the selective delivery and potentiation of anticancer drugs.