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11.
ABSTRACT

The retention of ethanol as a simulated flavour was determined by drying single droplets in a horizontal wind tunnel, with fructose, reconstituted skim milk or coffee as the flavour encapaulant. Droplet temperature histories, ethanol content, and crust structure were evaluated for each encapsulant. No enhancement of volatile retention was obtained with the fructose eolutions irrespective of initial concentration, air velocity, or air temperature. Enhancement of the volatiles retention with the coffee and skim milk solutions correlated with an increase in initial solide concentration. resulting from selective diffusion phenomena and the formation of a resistant skin. In both cases air velocity had no significant effect upon volatiles retention. Skin forming materials with similar characteristics would be advantageous for flavour retention.  相似文献   
12.
A series of random polyesteramides (PEAs) with a range of molar composition from 90/10 to 50/50 were synthesized by direct melt polycondensation of ε‐caprolactone and l ‐alanine. Their structure was fully characterized by Fourier transform IR and NMR spectroscopy. The resulting copolymers are completely amorphous with the exception of PEA‐90/10 which possesses a semicrystalline structure. These PEAs present increasing glass transition temperatures at increasing l ‐alanine contents and exhibit fairly good thermal stability with 10% mass loss temperatures reaching 315 °C. © 2020 Society of Industrial Chemistry  相似文献   
13.
The polydichlorophosphazenes were synthesized from hexachlorocyclotriphosphazenes by ring opening polymerization in the presence of AlCl3 as a catalyst. Poly[bis(ethyl salicylate)phosphazenes] (PESP) and poly[bis(ethyl salicylate diethylamino)phosphazenes] (PESDEAP) were synthesized via macromolecular substitution reactions using ethyl salicylate and (or) diethylamine as side groups. The synthesis results were proved by nuclear magnetic resonance (1H NMR, and 31P NMR) and gel permeation chromatography. In addition, the hydrolytic degradation of PESP and PESDEAP was investigated at constant temperature in neutral medium.  相似文献   
14.
In this paper, conditions for vertical weld defectless formation at horizontal electron-beam welding (EBW) are shown and power-complex selection methods to weld thick-walled constructions by electron beam are developed. Dependences to estimate EBW optimal conditions are obtained.  相似文献   
15.
New equipment and technologies for low-frequency vibrational treatment of components in engineering are examined. The design of new equipment and its technological characteristics are described, the technology of stress relieving after welding, casting, machining, etc. is discussed, and equipment for inspecting the stresses prior to and after treatment is analysed.  相似文献   
16.
Dehydrins (DHNs) play an important role in abiotic stress tolerance in a large number of plants, but very little is known about the function of DHNs in pepper plants. Here, we isolated a Y1SK2-type DHN gene “CaDHN3” from pepper. To authenticate the function of CaDHN3 in salt and drought stresses, it was overexpressed in Arabidopsis and silenced in pepper through virus-induced gene silencing (VIGS). Sub-cellular localization showed that CaDHN3 was located in the nucleus and cell membrane. It was found that CaDHN3-overexpressed (OE) in Arabidopsis plants showed salt and drought tolerance phenotypic characteristics, i.e., increased the initial rooting length and germination rate, enhanced chlorophyll content, lowered the relative electrolyte leakage (REL) and malondialdehyde (MDA) content than the wild-type (WT) plants. Moreover, a substantial increase in the activities of antioxidant enzymes; including the superoxide dismutase (SOD), peroxidase (POD), catalase (CAT), ascorbate peroxidase (APX), and lower hydrogen peroxide (H2O2) contents and higher O2•− contents in the transgenic Arabidopsis plants. Silencing of CaDHN3 in pepper decreased the salt- and drought-stress tolerance, through a higher REL and MDA content, and there was more accumulation of reactive oxygen species (ROS) in the CaDHN3-silenced pepper plants than the control plants. Based on the yeast two-hybrid (Y2H) screening and Bimolecular Fluorescence Complementation (BiFC) results, we found that CaDHN3 interacts with CaHIRD11 protein in the plasma membrane. Correspondingly, the expressions of four osmotic-related genes were significantly up-regulated in the CaDHN3-overexpressed lines. In brief, our results manifested that CaDHN3 may play an important role in regulating the relative osmotic stress responses in plants through the ROS signaling pathway. The results of this study will provide a basis for further analyses of the function of DHN genes in pepper.  相似文献   
17.
In this work,a degradable polyurethane composed of caprolactone(CL)and L-Lactide(LLA)as soft seg-ments,and 4,4'-methylenebis(cyclohexyl isocyanate)(H12MDI)and polytetramethylene ether glycol(PTMEG)as hard segments,was prepared.Hydrolytic degradation experiment revealed that the degrad-able polyurethane(PU)could be degraded in artificial seawater.It also showed that caprolactone-co-polyurethane(CL-PU)copolymer with higher crystallinity degraded much slower in artificial seawater.However,the introduction of LLA resulted in an increase in the hydrophilicity and reduction in the crys-tallinity of degradable PU,as demonstrated by the contact angle analysis.The result of the scanning elec-tron microscope showed that the surface of degradable PU renewed under static condition.Moreover,degradable PU was able to be used as a carrier,and it controlled the release rate of 4,5-dichloro-2-octyl-isothiazolone(DCOIT).The anti-diatom(Navicula incerta)test demonstrated that the(caprolactone-co-L-lactide)-co-polyurethane 4(CL/LAx-PU4)with DCOIT contents prevented the adhe-sion of diatom Navicula incerta(88.37%reduction)due to their self-polishing and the release of antifou-lants.Therefore,the degradable PU consisted of CL,LLA,and DCOIT could be a durable resin with good antifouling activity for the application in the marine anti-biofouling field.  相似文献   
18.
Cold uniaxial pressing of powder into a green body is a common forming process used in ceramic and pharmaceutical industries. Argillaceous particles are used as a model system to investigate granule failure during compaction. Indeed, the volume enclosed between the die and punches is reduced and the powder consolidates until a final height is obtained or a prescribed compacting pressure is reached. Desired properties of the green body are high strength, uniform density, no defects and fracture. In this work an experimental investigation has been focused on the ‘cracking cone’ fracture in powder compacts. This includes studies of crack propagation and determination of operating conditions to avoid the green body fracture. The numerical modelling is implemented using a finite element method based on the Von Mises criterion. A case of simulation is presented to demonstrate the ability of the model to compute the distribution of the relative stresses.  相似文献   
19.
The authors compared in a controlled clinical study two groups of patients after a first renal transplantation treated by triple drug immunosuppressive therapy. In a group of 31 patients the triple combination comprised Sandimmune Neoral. In the control group there were 30 patients who received Sandimmune. No differences were found between the two groups as regards the effectiveness of this treatment and the authors did not confirm a lower incidence of rejections described in patients treated with Sandimmune Neoral. They confirmed, however, a lower interindividual variability of Cy-A levels assessed specifically in patients treated with Sandimmune Neoral.  相似文献   
20.
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