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排序方式: 共有163条查询结果,搜索用时 31 毫秒
1.
展望21世纪新技术革命中的传感器   总被引:5,自引:2,他引:3  
在回顾了以往产业革命中传感器的作用 ,比较工程传感器与人的感官的异同点之后 ,阐述了预计将于 2 1世纪爆发的新产业革命中传感器的使命及发展趋势  相似文献   
2.
采用双束复合辐照装置,研究了He存在条件下,强辐照对长期时效后的ODS合金中强化相(Y2O3)的稳定性和辐照损伤特征的影响。实验结果表明:双束强辐照下,ODS合金中强化相不稳定,发生聚集长大并造成附近基体中Ti、Y浓度增高,导致空洞尺寸和空洞肿胀增加,并对这一结果从理论上进行解释。  相似文献   
3.
A new method was established to estimate the foaming properties of proteins from the conductivity of foams using a simple apparatus that consisted of a glass column with the conductivity cell. A close correlation was observed between the initial conductivity of foams and the foam volumes of heat-denatured ovalbumins or 11 native proteins, suggesting that the initial conductivity of foams can be used as a measure of foaming power. In addition, a close correlation was obtained between the foam stability determined from changes in the conductivity and foam volume with time of heat-denatured ovalbumins or 11 native proteins, suggesting that foam stability also can be estimated from changes in the conductivity of foams. The advantages of the conductivity measurements are to determine the foaming properties more simply and accurately than the currently used methods.  相似文献   
4.
The reersible association and dissociation of starch chain populations obtained from acid-treated starches (ATSs) was investigated. Potato starch, both nonglutinous and glutinous rice starches and sago starch were suspended in 15% sulfuric acid until 1% hydroysis occured. These ATSs had relative molecular weight ranges of 25,00–29,000 daltons. In water, about half the molecules were reconstituted into large aggregates of a few million daltons. This change in molecular size depended on presence of potassium chloride. It was not observed in debranched samples. The aggregates showed a clear endothermic peak on a DSC curve. Thus, the reversibly rearranging starch chain populations were not linear, but were branched and had some type of ordered structure.  相似文献   
5.
In this paper, Bacillus subtilis (natto) was incubated to develop a possible functional ingredient in ice cream. A lab‐scale culture revealed that incubation in the sterilised milk without dilution and concentration at 37°C for 28 h could obtain ideal growth characteristics of Bacillus subtilis (natto), especially with continuous aeration. Following freezing operation of the cultured milk, survival content of Bacillus subtilis (natto) was at 49–92%, while nattokinase activity was conserved at 62–98% comparing with the initial contents, which indicating a potential for application of natto functional ingredient in frozen milk products.  相似文献   
6.
EFFECTS OF VISCOSITY OF LIQUID FOODS ON PALATAL PRESSURE   总被引:1,自引:0,他引:1  
The deglutition of non-Newtonian liquids introduced into the mouth was studied dynamically by measuring palatal pressure (P) with pressure transducers set at three locations on the palate. The value of P and the swallowing pressure (S) changed only from 100 to 200 g/cm2 over the viscosity range 10−2 to 101 Pa.s. The retaining time (T) and work (W), required for swallowing after the liquid entered the mouth, remained almost constant up to a critical value of 1.0 Pa.s. above which both T and W increased markedly. When the viscosity was low, all of the liquid was swallowed in one deglutition, up to 15 mL volume. Therefore, T was almost constant but S increased with the volume. When the viscosity was high, the liquid was swallowed in several smaller portions. When the volume was high, T increased and S was either constant or it decreased.  相似文献   
7.
目的:研究大米分离蛋白和大豆分离蛋白对因雌性激素缺乏引起的高胆固醇血症的影响.方法:将24只Wistar成年雌鼠随机分为4组.3组大鼠进行双侧卵巢切除手术,分别喂食添加20%酪蛋白(对照组)、大米分离蛋白或大豆分离蛋白的饲料.另1组进行卵巢伪切除手术,喂食添加20%酪蛋白的对照饲料,喂养4周后解剖,测定血清和肝脏中胆固醇、甘油三酯浓度以及粪中胆汁酸排泄量和蛋白表观消化率等指标.结果:卵巢切除明显增加成年雌鼠血清和肝脏中胆固醇和甘油三酯浓度.与酪蛋白组相比,饲料中添加大豆分离蛋白能显著降低卵巢切除大鼠血浆总胆固醇和低密度脂蛋白及胆固醇浓度(p<0.05),但对血浆甘油三酯浓度无显著影响,同时明显降低肝重、肝脏中总脂、总胆固醇、游离胆固醇及甘油三酯总量,以及增加排粪量和胆汁酸排泄量,大豆分离蛋白表观消化率也明显比酪蛋白和大米分离蛋白高.大米分离蛋白对血脂没有明显降低效果,但肝脏总脂、总胆固醇、游离胆固醇和甘油三酯浓度明显低于酪蛋白饲料组,而排粪量、粪中胆汁酸排泄量和蛋白表观消化率则与酪蛋白组无显著差异.结论:抗消化蛋白对因雌性激素缺乏引起的高胆固醇血症有明显降低效果,可能的作用机制是由于该蛋白的低消化性干扰,肠道中胆汁酸代谢,增加粪中胆汁酸的排泄量来降低肝脏和血浆中胆固醇浓度.  相似文献   
8.
The sensory interactions of monosodium glutamate (MSG) and NaCl in a clear soup were examined by a sensory test, by a response-surface method. The extents of saltiness and palatability were expressed by second order polynomials of the concentrations of MSG and NaCl added. The polynomials indicated that to provide an appropriate saltiness and the maximum palatability score, more NaCl was required in soup with a lower MSG concentration, and vice versa. It is recommended that when the amount of sodium in the soup must be restricted while retaining a high palatability score, the NaCl level should be reduced while adding an optimal MSG level.  相似文献   
9.
 Tank模型可以模拟非线性的降雨–地下水运移过程,并且能迅速得到解答。基于现有的单列tank模型,提出新的复合水箱模型。由于新模型参数超过20个,应用传统优化算法难以快速找到最优解,一种新的启发式自搜索算法(变维数搜索算法)被引入并改进后用于模型最优解的寻找。变维数搜索算法能够根据搜索进程的变化自动改变搜索维数并且快速找到最优解。27个参数的复合tank模型被应用于日本国道九号线的一个边坡,计算结果表明:变维数搜索算法能够在10 min左右找到合适的最优解;降雨过程复合tank模型计算的地下水位变化和观测值非常接近。最后通过和有限单元法计算结果的比较表明,有限单元法的计算结果受地质渗透特性的影响很大,而复合tank模型不存在这种问题。工程实例计算表明,该方法和监测结果比较一致,但其适应性更强,特别适用于没有进行足够地质结构探查的边坡。它能够快速反映降雨过程中地下水位的运移过程,可以推广使用。  相似文献   
10.
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