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阐述了冰淇淋混合料液老化过程的条件控制及混合料在老化过程中发生的主要变化。经过老化过程,混合料液的黏度显著增加,有助于凝冻过程中的搅打起泡,使冰淇淋产品的质构更加细腻,抗融性和贮藏稳定性更好。  相似文献   

3.
采用胶体磨对香蕉皮中的膳食纤维进行处理,研究料液比、 pH值、温度、胶体磨齿间隙对膳食纤维水合性质的影响。通过单因素试验和正交试验,确定胶体磨最佳处理条件是料液比1∶2, pH值10,温度40℃,齿间隙10μm;测得的膳食纤维水合性质为水溶性12%,持水力9.78 g/g,膨胀力17.73 mL/g。  相似文献   

4.
The changes of electrical resistivity with time of cement pastes with water to cement ratio of 0.23, 0.35 and 0.53 were in situ continuously monitored by using electrodeless resistivity apparatus. Isothermal conduction calorimeter was also used to measure the hydration degree. The quantitative relationship between electrical resistivity evolution of paste and development of pore structure was proposed during hydration process. The results show that four stages (dissolution, induction, acceleration and deceleration) are identified according to the characteristics of electrical resistivity and its differential resistivity curves. In addition, a lower water to cement ratio shows a smaller capillary porosity and constriction factor as well as a higher tortuosity factor, resulting in a higher electrical resistivity of bulk paste, and the reverse phenomenon is observed with the electrical resistivity of pore solution.  相似文献   

5.
The hydration and hardening of the gypsum fluidized furnace slag cement is analysed by XRD and mercury pressure porosous meter combining with macroscopic experimental results. The additive, curing system affect material properties and why the water-tolerance is improved.  相似文献   

6.
早龄期约束水泥砂浆环开裂预测模型分析   总被引:2,自引:0,他引:2  
采用约束圆环试验研究了早龄期水泥砂浆的应力变化规律与开裂趋势。应用早龄期砂浆水化热模型、收缩与徐变等预测分析模型,建立了考虑温度、干缩与自收缩、徐变及硬化等多种效应综合作用下的约束水泥砂浆环早龄期时变应力分析模型,讨论了约束钢环与砂浆环的相对约束刚度对钢环约束效应的影响,提出了圆环开裂预测因子以分析约束水泥砂浆环的开裂趋势,与实际观察结果和数值分析结果的对比表明,上述理论分析与预测模型是合理并适用的。  相似文献   

7.
8.
The hydration process, activity and microstructure of composite cement-based materials containing fly ash(FA)and flue gas desulphurization gypsum(FGD)were investigated by using DTA-TG, XRD, SEM, hydration shrinkage and compressive strength tests. And then the hydration kinetics of composite cement-based materials was discussed and summarized. It is shown that the ettringite(AFt)DTA endothermic peak of the harden cement paste containing FA and FGD is stronger than that of the reference specimen. The secondary hydration effect of hardened FA-FGD cement paste is more obvious under the effects of mutually active excitation and the added activators. The results of SEM and XRD indicate that the AFt in harden cement paste is significantly found and the surface of FA particle is eroded, further illustrating that the early activity of composite cement-based materials is effectively motivated, and ensuring the comprehensive properties of hardened composite cement-based materials. On the other hand, the test results of microscopic test were confirmed by the hydration shrinkage and compressive strength tests. Therefore, this research and application of FA-FGD composite cement-based materials can consume a lot of industrial wastes discharged from the power plant. It is a kind of “green” building material.  相似文献   

9.
The influence of calcined alum on the hydration process, the structure and intensity of hardened anhydrite, the degree of solution supersaturation, and other properties are investigated by determining setting time, hydration rate and hydration temperature increases in combination with analyzing the microstructure and intensity of hardened paste. The alum action mechanism also is revealed. The results indicate that calcined alum is a highly active excitant for anhydrite. Calcined alum can reduce setting time, increase the hydration process and intensity of anhydrite, and refine crystals. Calcined alum improves the hydration and solution performance of anhydrite and sulfate radical concentration. This subsequently raises the degree of dihydrate gypsum supersaturation. Anhydrite hydration and solution, and the spontaneous homogeneous nucleation and growth of dihydrate gypsum crystals are all accelerated.  相似文献   

10.
Isothermal calorimeter, thermal analysis and scanning electron microscope were employed to investigate the impact of 3 polycarboxylate based superplasticizers (PCs) on the hydration behavior of tricalcium silicate (C3S). In addition, adsorption isotherm was measured by total organic carbon. The results indicate that PCs extends the induction period of C3S. Initial hydration process of C3S is markedly retarded, whereas acceleration is observed in the period of 28 d. And it is found that PC1, with maleic anhydride for its main chain, has the strongest retardation effect. The majority of the copolymer dispersants is remained in the pore solution. Moreover, linear relationship between the content of COO- and its retardation effect is established. Accordingly it is presumed that the critical supersaturation with respect to portlandite can be expected to have a profound impact because of the addition of PCs.  相似文献   

11.
The effect of dosage and modulus of water glass on the early hydration and setting performances of alkali-slag cement is very important. The variation of hydration heat and setting time and compressive strength of the alkali-slag cement with its modulus and alkali content are studied. It is found that with the increase of modulus, the hydration heat decreases and the setting time prolongs gradually, and the compressive strength increases first, then decreases. When the dosage of Na2O increases, the hydration heat increases. And the setting time increases slightly and the compressive strength shows the trend of increasing. The reasonable modulus of water glass Ms is about 1.0~2.0, and the dosage is about 3%~6% of the mass of slag.  相似文献   

12.
Hydration of the endosperm is a critical part of the malting process that ensures proper modification of the grain. However, little is known about the genetic controls of endosperm hydration and its relationship to agronomic and malt quality traits. The extent of endosperm hydration is estimated through hydration index (HYI). We measured HYI, agronomic, and malt quality traits on a 169-line subset of the NSGC Barley Core Panel, which includes global malt lines, some dating from the inception of European breeding programmes. Utilizing GWAS, 61 QTLs were identified for HYI, dormancy, agronomic, and malt quality traits. Of these, six were found to be related to HYI and were located on 1H, 2H, 3H, 6H, and 7H. We found HYI QTLs cosegregating with kernel size and hardness (1H and 3H), malting quality (2H and 6H), and dormancy (2H and 6H). These results indicate that endosperm hydration after steeping can be improved by selecting high HYI alleles on 2H, 6H, and 7H, positively impacting malting quality without negatively impacting kernel size or dormancy.  相似文献   

13.
According to an analysis of three-dimensional convection diffusion problems and object-oriented programming method,the classes of finite element models for convection diffusion problems are designed in C++.There are vector classes,matrix classes,element classes,material classes and method classes of finite element among these classes.On the basis of these classes,an object-oriented finite element program for three-dimensional convection diffusion problems is accomplished,which is able to simulate similar problems.The program's reuse,maintenance expansion and integration with other ones are easier than traditional ones which are designed with structural language,it can be applied to a large universal computational software for science and engineering.  相似文献   

14.
Both at 5°C and 20°C the sucrose concentrations between 8–14 % appear to be optimal from the point of view of dry mass accumulation by the seedling. The metabolic efficiency was also the highest for these concentrations of sucrose.
At both temperatures the hydration of the seedlings was strongly dependent on sucrose concentration in the nutrient, diminishing, respectively, from about 6 to about 2 and from about 10 to about 2 mg H2O × mg DW−1 Such low values of the seedling hydration, however, caused only a 10–20 % decrease of their dry weight. Within the range of the applied sucrose concentration (2–20 %) its beneficial – trophic interaction prevails over the negative – osmotic interaction.
At 5°C, as compared with 20°C, a drop in the seedlings hydration was observed, which appears to be the general response of plants to low temperature of growth.
An analysis of the 24-hour respiration rate of the seedlings when grown at 5°C seems to reveal the occurrence of a process requiring additional metabolic energy and, probably, associated with the vernalization process.
A method of leveling the temperature dependent hydration of the seedling is proposed to enable the selection of high-temperature control in the investigations of the biochemical mechanism of frost hardening and vernalization.  相似文献   

15.
The effect of compound retardant powder P on the hydration process,ion concentration in liuquid and supersaturation degree,and crystal morphology of dehydrate of FGD building gypsum is investigated.Furthormore,by using the SEM,its retarding mechanism is also studied.The results indicate that the addition of powder P retardant the early hydration of FGD building gypsum,which leads to delay of hydration heat evolution.It can also decrease the hydration ratio at early stage and prolong induction period of FGD building gypsum.Powder P has a major effect on the crystal morphology of dehydrate,moreover it enlarges crystal sizes.Retardation effect of powder P is worked by a variety of ways. The ionization of calcium ion from the hydroxyl carboxylic acid calcium salt definitely impedes the early dissolution of hemihydrate FGD building gypsum, delay the formation of nucleus.Also the selective absorption of groups composed of carboxyl and hydroxyl inhibits the growth of nucleus.Moreover the protein also plays a colloid coated role for gypsum,inhibiting the growth of nucleus.  相似文献   

16.
In this paper, by means of X-ray analysis and scanning electron microscope technology, the hydration and strength development of spontaneous gangue cement under the condition of normal atmospheric temperature and steam curing are analysed. This work provides experimental and theoretical basis for the usage of spontaneous combusted gangue cement.  相似文献   

17.
By adding small amount of dihydrate gypsum (CaSO4·2H2O) and silica fume in steel slag-cement system, steel slag-cement binding materials were prepared. And the dosage of CaSO4·2H2O and silica fume on the properties of steel slag-cement binding materials was studied. Hydration properties and paste structure were investigated by SEM and XRD. The results show that both CaSO4·2H2O and silica fume can improve the strength of steel slag-cement binding materials. Compared with single-doped, compound of CaSO4·2H2O and silica fume has much better effect on strength of steel slag-cement binding materials. The optimum proportion of CaSO4·2H2O and silica fume are 1% and 4%, respectively. The 3 d compressive strength is increased by 59.0%, and the 28 d compressive strength is increased by 36.5%. No matter adding CaSO4·2H2O and silica fume or not, the steel slag-cement binding materials have the same hydration products. However, the content of C-S-H gel and AFt crystals is higher, and the content of Ca(OH)2 crystals is lower in steel slag-cement binding materials containing CaSO4·2H2O and silica fume than those in steel slag-cement binding materials without CaSO4·2H2O and silica fume.  相似文献   

18.
The influences of the monocyclic aromatic high range water reducers on cement hydration were evaluated from four factors, such as hydration heat, hydration products, pore structure, microstructures of cement pastes. With measurement of hydration heat by the TAM Ai, it was found that monocyclic aromatic high range water reducer may delay early hydration and significantly decreased early hydration heat. And the monocyclic aromatic high range water reducers tended to increase porosity and pore volume of cement pastes with MRI analysis, while pore size distribution did not change remarkably. With analysis of XRD、TG DTA and SEM, it was shown that the monocyclic aromatic high range water reducers could restrain the production of Ca(OH)2 and Hydrated Calcium Silicates in the hydration process without affecting the end products, and refine the hydration products, such as Ca(OH)2, C S H gel and ettringite crystals.  相似文献   

19.
Manganese alloy slag is an industrial waste produced from manufacture of manganese alloy. Recent years environment pollution of manganese slag has been becoming heavier and heavier with the development of manganese industry. Aiming to sort out this problem, combination of manganese slag and ground granulated blastfurnace slag (GGBS) were applied to prepare alkali activated cementitious material. Compressive strength and flexural strength of cementitious material prepared with combination of alkali slag manganese slag were measured. And micro structure of hydration production was investigated by scanning electro microscope (SEM). It was shown that the flexural and compressive strength of cementitious material with alkali GGBS manganese slag system were decreased with the increase of replacement of GGBS by manganese slag. The increase of the fineness of manganese slag was favorable for strength improvement of the alkali GGBS manganese slag material. It was concluded that ground manganese slag had hydraulic activity in alkali activated cementitious material and the activity was lower than that of GGBS.  相似文献   

20.
非破坏性方法测定小麦种子活力研究   总被引:9,自引:0,他引:9  
低温10℃贮存6个月后,重复吸水-回干处理有提高小麦种子活力的作用,但高温35℃贮存6个月后,除1次浸泡2h或4h的处理处,其他处理随浸泡时间的延长和浸泡次数的增加种子活力明显下降。两种温度贮藏后,整粒种子的过氧化物酶和酯酶同工酶谱带变化处理与对照间无明显差异,电导率,可溶糖糖,氨基酸和紫外光密度4项种子渗漏物测定指标中,可溶性糖含量与种子活力密切相关。最终筛选出一个非破坏小麦种子活力的监测方法,即:小麦种子浸光2h或4h后,种子在室温下经适当干燥至原含水量后可继续保存,浸泡液被用于测定可溶性糖含量。  相似文献   

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