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关键词： Yellow mealworm (tenebrio molitor)   House cricket (acheta domesticus)   Insects   high hydrostatic pressure assisted extraction (HHP-e)   Insect oil  

摘要： Oil portion of Tenebrio molitor (yellow mealworm) and Acheta domesticus (house cricket) were examined and it was investigated how the physicochemical properties of the oils changed with High Hydrostatic Pressure Assisted Extraction (HHP-E) and conventional solvent extraction (CE) with hexane. The effect of HHP-E at 500 MPa and 30 and 40 degrees C for 15 min on the properties of oils was compared with the CE. Following the extraction of oil, fatty acid composition, peroxide value, crystallization and melting points, total phenolic content and antioxidant activities were determined. Oil yield was found in the range of 22.75-24.22% for mealworm and 16.17-18.09% for cricket with significant amount of Omega-3 and Omega-6 fatty acids. Fatty acid composition of insect oils was significantly affected from HHP-E and extraction temperature (p < 0.05). The difference between crystallization and melting point of mealworm were found to be higher than cricket (p < 0.05). HHP-E insect oil had desirable characteristics to be used as a food ingredient. [GRAPHICS] .

关键词： Bovine bone   collagen   emulsion‐   type sausage   ossein  

摘要： Ossein (OS) powder was prepared from bovine bone, ground and sieved through mesh screens to obtain two different particle sizes of 50 (OS50) and 200 mesh (OS200). Regarding OS property determination, average particle diameters of the OS50 and the OS200 were 260.08 +/- 6.48 mu m and 51.79 +/- 0.39 mu m, respectively. Based on non-reducing electrophoresis, both OS samples consisted of alpha 1- and alpha 2-chain of type I collagen. Fourier transform infrared spectra revealed the presence of triple helical structure with partial unfolding of which the OS200 showed the greater denaturation extent. The OS200 also showed higher emulsion activity but lower oil absorption than those of the OS50. The emulsion-type sausages containing OS powders (0.5% w/w) exhibited significantly lower total fluid, water, and fat releases than those of the sausages without OS. The OS200-containing sausages exhibited the lowest expressible water and received the highest hedonic scores in texture and overall acceptance from consumer panel.

关键词： Culicoides   African horse sickness   Larval habitat   Physicochemical parameters   Niayes area   Senegal  

摘要： Biting midges of the genus Culicoides (Diptera: Ceratopogonidae) are the biological vectors of arboviruses of global importance in animal health. We characterized the physicochemical parameters that determine the density and composition of the main Culicoides species of veterinary interest in larval habitats of the Niayes region of Senegal. For this purpose, we combined larval and substrate sampling in the field in different habitat types with adult emergence and physicochemical analyses in the laboratory. Three major habitat types were identified, conditioning the predominant species of Culicoides and pH and the amount of organic matter were positively correlated with the abundance of larvae and emerging Culicoides, as opposed to salinity. The diversity of emerging Culicoides was positively correlated with pH while it was negatively correlated with salinity. Culicoides distinctipennis was the predominant species in the larval habitat group of freshwater lake edges. In the larval habitat group of pond and puddle edges, C. oxystoma and C. nivosus were predominant;both species were again most abundant in the larval habitat group of saltwater lake edges. These variabilities in physicochemical parameters support the distribution of different Culicoides species in different habitat groups. These results make it possible to implement effective, selective and environmental-friendly control measures but also to improve current models for estimating the abundance of adult vector populations at a local scale.

关键词： Antioxidants   Bioaccessibility   Cactaceae   Proximate composition   Unconventional food plants  

摘要： Xique-xique (Pilosocereus gounellei) is a cactus found in the Caatinga biome which is used in folk medicine for treating inflammation, and also used in animal food. This study evaluated its proximate composition and bioactive compounds, as well as its bioaccessibility and antioxidant activity. Experiments were performed on different parts of the plant. The central stem of the xique-xique can be considered a source of insoluble dietary fiber (5.18 g/100 g) and soluble fiber (1.37 g/100 g). The vascular cylinder contained the highest mineral content: K (308.4 mg/100 g), Ca (145.57 mg/100 g), Mg (182.40 mg/100 g), and Mn (7.71 mg/100 g). The vascular cylinder group presented the highest activity for capturing DPPH radicals (572.96 mu M of TEAC/100 g) and ferric reducing ability (1912.95 mu M of TEAC/100 g). Catechin and epigallocatechin-gallate were the major phenolic compounds, while catechin, epigallocatechin gallate and procyanidin B and gallic acid were the most bioaccessible compounds after in vitro gastrointestinal digestion. Xique-xique can be considered as a potential food alternative with nutritional value and bioactive compounds, indicating its potential use and enrichment in various food products.

关键词： Gamma irradiation   Metal complexes   Spectral   X-ray diffraction   Molecular modeling   Antimicrobial screening activity  

摘要： A series of Co(II), Ni(II), Cu(II), Th(IV) and UO2(II) complexes have been synthesized from reaction of nitrogen based ligand (L) i.e. N',N'''-((Z)-ethane-1,2-diylidine)bis(2-aminobenzohydrazide)(L)with their salts. Investigation of synthesized metal complexes was achieved by using elemental analyses, magnetic moment, molar conductance, FT-IR, UV/Vis. spectroscopy, thermal techniques and 3D molecular modeling. An octahedral geometry has been suggested for all complexes except for Ni(II) complex (2) which adopted tetrahedral geometry. To through a light on the probability of structure changes with gamma-irradiation, the effect of gamma irradiation on powder samples of the complexes [Co(L)Cl-2]center dot 4H(2)O (1);[Ni-2(L)(OAc)(4)]center dot 5H(2)O (2) and [Cu(L)Br-2]center dot 5H(2)O (3) was investigated after being exposed to high energetic gamma-rays at 100 kGy dose (hereafter referred to as (1A,2A,3A, respectively). Spectral, thermal, magnetic susceptibility, molar conductance and powder X-ray diffraction patterns (XRD) were performed before and after irradiation. In addition, the in vitro antimicrobial activity of the complexes against Staphylococcus aureus as Gram-positive strain, Escherichia coli as Gram-negative strain and antifungal Candida albicans was performed for both unirradiated and irradiated samples. The obtained results showed that the irradiated complexes were affected, but not greatly by the applied gamma-irradiation dose.

关键词： Dental materials   Dental prosthesis   Dental implants  

摘要： Objectives. To characterize the physicochemical and mechanical properties of a milled fiber-reinforced composite (FRC) for implant-supported fixed dental prostheses (FDPs). Methods. For FRC characterization, scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), X-ray diffraction, Fourier-transformed infrared spectrometry, simultaneous thermogravimetric analysis and differential scanning calorimetry were performed. For fatigue testing, 3-unit FRC frameworks were fabricated with conventional (9 mm(2) connector area) and modified designs (12 mm(2) connector area and 2.5 mm-height lingual extension). A hybrid resin composite was veneered onto the frameworks. FDPs were subjected to step -stress accelerated-life fatigue testing until fracture or suspension. Use level probability Weibull curves at 300 N were plotted and the reliability for 100,000 cycles at 300, 600 and 800 N was calculated. Fractographic analysis was performed by stereomicroscope and SEM. Results. The FRC consisted of an epoxy resin (similar to 25%) matrix reinforced with inorganic particles and glass fibers (similar to 75%). Multi-layer continuous regular-geometry fibers were densely arranged in a parallel and bidirectional fashion in the resin matrix. Fatigue analysis demonstrated high probability of survival (99%) for FDPs at 300 N, irrespective of framework design. Conventional FDPs showed a progressive decrease in the reliability at 600 (84%) and 800 N (19%), whereas modified FDPs reliability significantly reduced only at 800 N (75%). The chief failure modes for FRC FDPs were cohesive fracture of the veneering composite on lower loads and adhesive fracture of the veneering composite at higher loads. Significance. Milled epoxy resin matrix reinforced with glass fibers composite resulted in high probability of survival in the implant-supported prosthesis scenario. (C) 2021 Published by Elsevier Inc. on behalf of The Academy of Dental Materials.

关键词： 物理化学   化学实验   高等学校   教材  

ISBN: (纸本)9787564382124

摘要： 本教材主要面向民族院校化学类、生命科学类、环境类专业的本科学生，主要内容分为五大部分，分别是热力学实验（五个）、电化学实验（三个）、动力学实验（两个）、表面物理化学（六个）、综合实验（两个）。实验课程安排与物理化学理论课程安排基本一致，力求帮助学生通过实际操作来加深理解理论知识，锻炼逻辑思维能力、动手能力以及解决简单问题的能力。本教材实用性较强，在实验原理和实验操作的讲解方面相对同类教材更为细致，更注意使用较为详尽的描述以帮助同学更好地完成实验。

关键词： Waxy potato starch   Physical modification   De-structuring   Thermal degradation   Shear-thickening   Anti-thixotropy  

摘要： This study focuses on the physico-chemical properties of a ?clean-label? modified starch (de-structured starch) as a potential food ingredient. The modified starch was obtained by the disassembly of native waxy potato starch granules into its macromolecular chains. Waxy potato starch samples were treated at elevated temperatures of 120, 130, 140, and 150 ?C for 30 min at a stirring speed of 300 rpm in a high pressure reactor. Starch treated at 120 ?C showed similar molar mass as its native form indicating that treatment at 120 ?C had resulted in the disassembly of the starch granules into its macromolecular chains. Reduction in viscosity and particle size was observed with increased temperature from 120 to 150 ?C. The reduction in viscosity and size was not only attributed to the disassembly of starch granules into its macromolecular fractions but also due to a further size reduction of amylopectin chains. De-structured starch treated at 140 and 150 ?C exhibited flow behavior approaching Newtonian fluid. However, de-structured starch treated at 120 and 130 ?C exhibited shearthickening behavior above their critical shear rates at 14 and 27 s-1 respectively. Shear-induced interactions among starch macromolecular fractions appeared to have occurred within a narrow range of heat treatment (120 and 130 ?C) but not in more severely heat-treated starches (140 and 150 ?C).

关键词： Manure application   Aggregate stability   Aggregate-associated carbon   Soil physicochemical characteristics   Alkaline soil  

摘要： The response to climate change through soil organic carbon sequestration has received increased interest. While soil organic carbon sequestration is related to the stability of aggregates and aggregate-associated carbon and varies among fertilization practices, little information is available on how fertilization practices impact the stability of aggregates and aggregate-associated carbon in alkaline soil. Using a 13-year field experiment with three replicate plots of four fertilization practices (only chemical fertilizer application, only manure application, 50% chemical fertilizer and 50% manure application, and 100% chemical fertilizer and 100% manure application) and one control treatment (nonfertilization), we investigated the correlations between 20 soil physicochemical factors and stability indices of aggregates and aggregate-associated carbon under the influence of long-term fertilization. Fertilization with manure not only significantly improved soil physicochemical characteristics, such as increasing conductivity, the cation exchange capacity, organic carbon, and the availability of nutrients and calcium/magnesium, but also enhanced mean weight diameter, geometric mean diameter and large aggregate- and microaggregate-associated carbon. Soil organic carbon was more abundant in large aggregates and microaggregates than in other fractions, and the carbonyl group bands in large aggregates were wider than those in other fractions. Mean weight diameter, geometric mean diameter and large aggregate- and microaggregate-associated carbon were positively correlated with the total amounts and availabilities of soil nutrients and free and exchangeable calcium/magnesium and were negatively correlated with soil pH, likely because fertilization with manure enhanced the stability of aggregates and aggregate-associated carbon by increasing the availability of soil nutrients and calcium/magnesium ions, while high pH limited the stability of aggregates and aggregate-associate

关键词： Coconut water   Microbiological properties   Physicochemical properties   Storage  

摘要： The effect of storage temperature and time on physicochemical (total soluble solids, pH, titratable acidity, and optical density) and microbiological (total plate count and yeast and mould count) properties of green (GC) and mature coconut (MC) water were determined between 4 and 35 degrees C for up to 24 h. When held at temperatures above 25 degrees C, total soluble solids of coconut water reduced slightly, whereas pH decreased concomitantly with the increase in titratable acidity. These changes correlate positively with storage temperature and occurred at a faster rate in MC water than in GC. Both GC and MC could be held at temperatures between 25 and 35 degrees C for up to 12 and 6 h, respectively, after which the samples could become acidified and microbiologically unsafe to be consumed. At 4 degrees C, both GC and MC could be held for 24 h with acceptable microbiological counts.