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International Journal of Thermophysics - The addition of nanoparticles to base fuel may bring about remarkable changes in a thermodynamic process such as evaporation, due to the intensified...  相似文献   
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首先研究不同红外辐射温度(100,110,120℃)及辐射时间(2.5,5,10 min)对胡萝卜粉微生物及品质的影响,然后根据栅栏效应原理研究红外辐射-回火、红外辐射-冷激联合杀菌对胡萝卜粉微生物、色调值、类胡萝卜素含量等品质的影响。结果表明:100℃、10 min的红外辐射处理使细菌和真菌分别降低了1.9 lg(CFU/g)和2.32 lg(CFU/g),110℃、5 min的红外辐射处使细菌和真菌分别降低了1.58 lg(CFU/g)和2.57 lg(CFU/g)。在上述两种处理条件下胡萝卜粉的水分活度从0.238分别降至0.123和0.147,胡萝卜粉中总类胡萝卜素含量从308.8μg/g降至227.8μg/g和238.8μg/g,色差值(ΔE)为9.11和7.89。与红外辐射单独作用相比,联合回火后的处理没有显著影响细菌数目,处理后保持在5.40~5.80 CFU/g,霉菌、酵母数却在处理过程中显著减少,然而减少量较低,总数仍不低于4.5 lg(CFU/g)。红外辐射-冷激联合处理相比红外辐射单独处理,100℃、10 min联合冷激7 d处理可将细菌数量降低0.25 lg(CFU/g),可将霉菌与酵母数量降低0.28 lg(CFU/g),110℃、5 min联合冷激7 d处可将细菌数量降低0.26 lg(CFU/g),可将霉菌、酵母数量降低0.40 lg(CFU/g),且这些处理下胡萝卜粉的色调值、水分活度、类胡萝卜素含量变化不显著。本试验结果表明,红外辐射-冷激处理具有协同效应,且处理过程中胡萝卜粉的色调值及总类胡萝卜素含量不受影响,这为低水分粉体食品红外辐射联合杀菌提供了参考。  相似文献   
4.
The muon radiography imaging technique for high-atomic-number objects(Z) and large-volume objects via muon transmission imaging and muon multiple scattering imaging remains a popular topic in the field of radiation detection imaging. However, few imaging studies have been reported on low and medium Z objects at the centimeter scale. This paper presents an imaging system that consists of three layers of a position-sensitive detector and four plastic scintillation detectors. It acquires data by co...  相似文献   
5.
A strategy for creating potent and pan-genotypic stimulator of interferon genes (STING) agonists is described. Locking a bioactive U-shaped conformation of cyclic dinucleotides by introducing a transannular macrocyclic bridge between the nucleic acid bases leads to a topologically novel macrocycle-bridged STING agonist (MBSA). In addition to substantially enhanced potency, the newly designed MBSAs, exemplified by clinical candidate E7766 , exhibit broad pan-genotypic activity in all major human STING variants. E7766 is shown to have potent antitumor activity with long lasting immune memory response in a mouse liver metastatic tumor model. Two complementary stereoselective synthetic routes to E7766 are also described.  相似文献   
6.
Laser aided additive manufacturing(LAAM)was used to fabricate bulk Fe49.5Mn30Co10Cr10C0.5 interstitial multicomponent alloy using pre-alloyed powder.The room temperature yield strength(σy),ultimate tensile strength(σUTS)and elongation(εUST)were 645 MPa,917 MPa and 27.0%respectively.The as-built sample consisted of equiaxed and dendritic cellular structures formed by elemental segregation.These cellular structures together with oxide particle inclusions were deemed to strengthen the material.The other contributing components include dislocation strengthening,friction stress and grain bound-ary strengthening.The high εUTS was attributed to dislocation motion and activation of both twinning and transformation-induced plasticity(TWIP and TRIP).Tensile tests performed at-40℃and-130℃demonstrated superior tensile strength of 1041 MPa and 1267 MPa respectively.However,almost no twinning was observed in the fractured sample tested at-40℃and-130℃.Instead,higher fraction of strain-induced hexagonal close-packed(HCP)ε phase transformation of 21.2%were observed for fractured sample tested at-40℃,compared with 6.3%in fractured room temperature sample.  相似文献   
7.
为推进病历数字化发展,并确保其信息的安全性,将以HIS电子病历系统为基础,采用安信数字签名技术和PKI或PMI系统搭建相信并加以任用的授权服务,经过针对实际的PKC和CA的确认、委托与管控构建整体的数字签名平台,完成电子病历数字签名功能设计,以加强电子文件的完整性、真实性和不可抵赖性。最后以某医院的XML结构化的电子病历系统为基础进行项目实施,完成了医护人员通过HIS的快速身份认证,和准确地数字签名。  相似文献   
8.
Due to the demand of miniaturization and integration for ceramic capacitors in electronic components market, TiO2-based ceramics with colossal permittivity has become a research hotspot in recent years. In this work, we report that Ag+/Nb5+ co-doped (Ag1/4Nb3/4)xTi1−xO2 (ANTOx) ceramics with colossal permittivity over a wide frequency and temperature range were successfully prepared by a traditional solid–state method. Notably, compositions of ANTO0.005 and ANTO0.01 respectively exhibit both low dielectric loss (0.040 and 0.050 at 1 kHz), high dielectric permittivity (9.2 × 103 and 1.6 × 104 at 1 kHz), and good thermal stability, which satisfy the requirements for the temperature range of application of X9R and X8R ceramic capacitors, respectively. The origin of the dielectric behavior was attributed to five dielectric relaxation phenomena, i.e., localized carriers' hopping, electron–pinned defect–dipoles, interfacial polarization, and oxygen vacancies ionization and diffusion, as suggested by dielectric temperature spectra and valence state analysis via XPS; wherein, electron-pinned defect–dipoles and internal barrier layer capacitance are believed to be the main causes for the giant dielectric permittivity in ANTOx ceramics.  相似文献   
9.
Hydrothermal reaction in Cerium and Gadolinium solution as an optimization method is developed and first reported for the densification of gadolinia doped ceria, the barrier layer between Zirconia electrolyte and (La,Sr)(Co,Fe)O3-δ cathode. This method is based on the hydrothermal reaction for nano particles in-situly grown on porous surface, to improve barrier layer density, alongside the sintering of cathode at 1075 °C. As a result, the ohmic resistance is prominently decreased by ~16.4 % at 750 °C for electrolyte supported symmetrical cell. Whereas, the cathode polarization resistance is decreased by as much as a factor of ~3 from 0.3702 Ω·cm2 to 0.1325 Ω·cm2 at 750 °C and pO2=0.21atm. Furthermore, the anode supported cell exhibits higher open circuit voltage, smaller area specific resistance, elevated performance output and less degradation. And this modified barrier layer shows reduced Sr migration in 300 h operation at 750 °C. The hydrothermal reaction is demonstrated to prepare denser and sintering-active barrier layer with faster oxygen ion transfer and better interface connection, with large-scale application prospects and cost-competitiveness.  相似文献   
10.
An easy albeit quite effective deionization suspension treatment was adopted to alleviate the detrimental effects related to the hydrolysis of Y2O3 in an aqueous medium. Fabrication of highly transparent Y2O3 ceramics with a fine grain size via air pre-sintering and post–hot isostatic pressing (HIP) treatment without using any sintering additive was achieved using the treated suspensions. The hydrolysis issue of Y2O3 powder in an aqueous medium was effectively alleviated by using deionization treatment, and a well-dispersed suspension with a low concentration of dissolved Y3+ species was obtained. The dispersed suspensions were consolidated by the centrifugal casting method, and the green bodies derived from the suspension of 35.0 vol% solid loading showed an improved homogeneity with a relative density of 52.1%. Fully dense Y2O3 transparent ceramic with high transparency was obtained by pre-sintering consolidated green compacts at a low temperature of 1400°C for 16 h in air followed by a post-HIP treatment at 1550°C for 2 h under 200 MPa pressure. The sample had a fine average grain size of 690 nm. The in-line transmittance of the sample reached 83.3% and 81.8% at 1100 nm and 800 nm, respectively, very close to the theoretical values of Y2O3.  相似文献   
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