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1.
Abstract: We have previously reported that bilberry anthocyanins exhibit an anti‐pruritic effect in a mouse model of allergic contact dermatitis. It has been reported that anthocyanins are particularly sensitive to thermal treatment and are easily hydrolyzed to anthocyanidins when exposed to high temperatures. The objective of this study was to compare the anti‐pruritic effect of anthocyanin‐rich quality‐controlled bilberry extract and anthocyanidin‐rich degraded extract using a mouse model of allergic contact dermatitis. BALB/c mice with allergic contact dermatitis induced by 4 weeks of repeated application of 2,4,6‐trinitro‐1‐chlorobenzene (TNCB) were administered Bilberon‐25 orally for 4 weeks after sensitization with TNCB. The effect of Bilberon‐25 on pruritus was evaluated by measurement of scratching behavior. RBL‐2H3 mast cells were used to investigate the effect of Bilberon‐25 on degranulation in 48/80‐stimulated mast cells. Compared with nonheated Bilberon‐25, the proportion of anthocyanins in heated Bilberon‐25 decreased, and the proportion of anthocyanidins was increased in heated‐time dependent manner. Treatment with non‐heated Bilberon‐25 significantly attenuated the TNCB‐induced increase in scratching behavior, whereas treatment with 2 h‐heated Bilberon‐25 did not. Moreover, 300 μg/mL nonheated Bilberon‐25 showed significant inhibition of degranulation in RBL‐2H3 mast cells, whereas 2 h‐heated Bilberon‐25 had no effect at any concentration studied. It is assumed that the inhibitory effect of bilberry anthocyanins on pruritus might be mediated, at least in part, by its inhibitory effect on mast cell degranulation. In conclusion, the anthocyanin‐rich but not anthocyanidin‐rich bilberry extract may be a useful dietary supplement for skin diseases involving pruritic symptoms, such as chronic allergic contact dermatitis, atopic dermatitis, and rhinitis.  相似文献   
2.
In present study, the collapse of void bubble in liquid has been simulated using moving particle semi-implicit (MPS) code. The liquid is described using moving particles and the bubble–liquid interface was set to be vacuum pressure boundary without interfacial heat mass transfer. The topological shape of bubble can be traced according to the motion and location of interfacial particles. The time dependent bubble diameter, interfacial velocity and bubble collapse time were obtained under wide parametric range. The comparison with Rayleigh and Zababakhin's prediction showed a good agreement which validates the applicability and accuracy on MPS method in solving present momentum problems. The potential void induced water hammer pressure pulse was also evaluated which is instructive for further material erosion study. The bubble collapse with non-condensable gas has been further simulated and the rebound phenomenon was successfully captured which is similar with vapor-filled cavitation phenomenon. The present study exhibits some fundamental characteristics of void bubble hydrodynamics and it is also expected to be instructive for further applications of MPS method to complicated bubble dynamics problems.  相似文献   
3.
The performance of the super-critical water-cooled fast reactor (Super FR) for the transmutation treatment of long-lived fission products (LLFPs) was evaluated. Two regions with the soft neutron spectrum, which is of great benefit to the LLFPs transmutation, can be utilized in the Super FR. First region is in the blanket assembly due to the ZrH1.7 layer which was utilized to slow down the fast neutrons to achieve a negative void reactivity. Second region is in the reflector region of core like other metal-cooled fast reactors. The LLFPs selected in the transmutation analysis include 99Tc, 129I and 135Cs discharged from LWR or fast reactor. Their isotopes, such as 127I, 133Cs, 134Cs and 137Cs were also considered to avoid the separation. By loading the isotopes (99Tc or 127I and 129I) in the blanket assembly and the reflector region simultaneously, the transmutation rates of 5.36%/GWe year and 2.79%/GWe year can be obtained for 99Tc and 129I, respectively. The transmuted amounts of 99Tc and 129I are equal to the yields from 11.8 and 6.2 1000 MWe-class PWRs. Because of the very low capture cross section of 135Cs and the effect of other cesium isotopes, 135Cs was loaded with three rings of assemblies in the reflector region to make the transmuted amount be larger than the yields of two 1000 MWe-class PWRs.Based on these results, 99Tc and 129I can be transmuted conveniently and higher transmutation performance can be obtained in the Super FR. However, the transmutation of 135Cs is very difficult and the transmuted amount is less than that produced by the Super FR. It turns out that the transmutation of 135Cs is a challenge not only for the Super FR but also for other commercial fast reactors.  相似文献   
4.
The role of manganese ions in neural functions is poorly understood because of the low level of manganese in the brain. An excess of this ion is associated with neurological disorders such as extrapyramidal symptoms. We demonstrated that manganese may be taken up by piriform neurons (tertiary olfactory neurons) after release from the terminals of secondary olfactory neurons, in which 54Mn taken up by the soma may be anterogradely transported [A. Takeda, Y. Kodama, S. Ishiwatari, S. Okada, Manganese transport in the neural circuit of Rat CNS, Brain Res. Bull. (45) (1998) 149-152]. Here we demonstrate for the first time that 54Mn previously taken up into the amygdala is released with neurotransmitters into the extracellular space during stimulation with high K+. The results suggest that the role of manganese ions in the amygdala, and probably in the olfactory system, is dynamically linked to neural signalling processes.  相似文献   
5.
A rat embryo fibroblast (REF) cDNA expression library was transfected into 3Y1 cells transformed by human papillomavirus type 18 E6 and E7 genes and 10 flat revertants were isolated. These revertants expressed the same levels of E6 and E7 mRNA as the parent cells, but had greatly reduced ability to form colonies in soft agar. Suppression of transformation was dominant in cell hybrids generated by fusing each revertant with the parental transformed cells. Furthermore, loss of transfected cDNA was observed in re-transformed cell hybrids derived from one flat revertant. Overexpression of the cDNA suppresses the colony-forming efficiency of the cells transformed by E6 and E7 genes.  相似文献   
6.
In the present study, single steam bubble condensation behaviors in subcooled water have been simulated using Moving Particle Semi-implicit (MPS) method. The liquid phase was modeled using moving particles and the two phase interface was set to be a movable boundary which can be tracked by the topological position of the interfacial particles. The interfacial heat transfer was determined according to the heat conduction through the interfacial liquid layer and the coupling between momentum and energy was specially treated. Computational results showed that the bubble experiences various deformations at lower degrees of liquid subcooling while it remains nearly spherical at higher degrees of liquid subcooling. The bubble lifetime is nearly proportional to bubble size and is prolonged at higher system pressures. Bubble lifetime obtained from the MPS method agrees well with the experiments of 10 and 11, however it is lower than the predictions of Sudhoff et al. (1982). The underestimation is caused by severe bubble deformation at lower degrees of subcooling. The present study exhibits some fundamental characteristics of single steam bubble condensation and is expected to be instructive for further applications of the MPS method to evaluate more complicated bubble dynamics problems.  相似文献   
7.
Traditional (low temperature, long time) and novel (low temperature, short time) sous‐vide cooking of lean tuna were characterized by analyzing the effects of thermal protein denaturation (TPD) on quality attributes, such as color, appearance, shrinkage, drip loss, and texture. TPD was analyzed by differential scanning calorimetry and estimated for several thermal schedules by kinetic analysis, following the dynamic method. When heated at a rate of 10 °C/min, myosin began to denature at around 35 °C. Actin did not denature, even when the temperature rose to approximately 51 °C, until the denaturation of myosin was complete. However, actin began to denature at approximately 58 °C and was completely denatured at 76 °C. Actin denaturation had a stronger effect than myosin denaturation on texture changes, whereas myosin denaturation was responsible for changes in color and appearance. A better preservation of tuna quality was obtained by novel sous‐vide cooking over the traditional sous‐vide method.

Practical applications

The results of this study are useful to both the research community and industry because they provide quantitative characterization of the consequences of sous‐vide cooking method on food quality explained by estimating TPD. Moreover, the kinetic parameters of the denaturation rate collected for kinetic modeling of the TPD of tuna, not only have application to simulate denaturation of actin and myosin under different thermal schedules of sous‐vide cooking, but also they can be used for the analysis of additional thermal treatments.  相似文献   
8.
A procedure for estimating values that are proportional to the mean activity coefficients of sodium 4′-dialkylaminoazobenzene-4-sulphonates in cellophane is presented. These values are derived from the mean activity coefficients of the dye in solution, and the dye concentrations in solution and in cellophane.  相似文献   
9.
Keeping negative void reactivity throughout the cycle life is one of the most important requirements for the design of a supercritical water-cooled fast reactor (super fast reactor). Previous conceptual design has negative overall void reactivity. But the local void reactivity, which is defined as the reactivity change when the coolant of one fuel assembly disappears, also needs to be kept negative throughout the cycle life because the super fast reactor is designed with closed fuel assemblies. The mechanism of the local void reactivity is theoretically analyzed from the neutrons balance point of view. Three-dimensional neutronics/thermal-hydraulic coupling calculation is employed to analyze the characteristics of the super fast reactor including the local void reactivity. Some configurations of the core are optimized to decrease the local void reactivity. A reference core is successfully designed with keeping both overall and local void reactivity negative. The maximum local void reactivity is less than −30 pcm.  相似文献   
10.
Heat transfer coefficient and pressure drop were measured for condensation and evaporation of R410A and HCFC22 inside internally grooved tubes. The experiments were performed for a conventional spiral groove tube of 8.01 mm o.d. and 7.30 mm mean i.d., and a herring-born groove tube of 8.00 mm o.d. and 7.24 mm mean i.d. To measure the local heat transfer coefficients and pressure drop, the test section was subdivided into four small sections having 2 m working length. The ranges of refrigerant mass flow density was from 200 to 340 kg/(m2 s) for both condensation and evaporation of R410A and HCFC22, and the vapour pressure was 2.41 MPa for condensation and 1.09 MPa for the evaporation of R410A. The obtained heat transfer data for R410A and HCFC22 indicate that the values of the local heat transfer coefficients of the herring-bone grooved tube are about twice as large as those of spiral one for condensation and are slightly larger than those of spiral one for the evaporation. The measured local pressure drop in both condensation and evaporation is well correlated with the empirical equation proposed by the authors.  相似文献   
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