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101.
Vu Van Hung Pham Dinh Tam K. Masuda-Jindo S. R. Nishitani 《Journal of Phase Equilibria and Diffusion》2001,22(4):400-405
The thermodynamic properties of metals and alloys are studied using the moment method in the statistical dynamics, which allows
us to take into account the anharmonicity of thermal lattice vibrations and size mismatch of constituent atoms, going beyond
the quasi-harmonic approximation. Within the fourth-order moment approximation, the free energy and equilibrium lattice spacing
of the binary alloys are given explicitly in terms of the effective pair potentials and the second- and fourth-order vibrational
constants. The long-range order (LRO) parameter η and order-disorder transition temperatures (ODTs) Tc of binary alloys are obtained by solving the explicit transcendental equations. The numerical calculations of thermodynamic
quantities for Cu3Au and β-CuZn alloys show that the inclusion of the anharmonicity of lattice vibration plays an essentially important role in determining
the phase stabilities of metals and alloys. 相似文献
102.
We measured the incidence of cuff retear and injury to the suprascapular nerve after mobilization and repair of a massive rotator cuff tear. Of one hundred four rotator cuff repairs performed over a 5-year period, 10 patients (7 men and 3 women, age range 22 to 68 years) had primary repairs of massive rotator cuff tears requiring cuff mobilization and an acromioplasty as their only procedure. These patients were evaluated at a mean of 2.5 years (range 2.0 to 3.0 years) after surgery. At follow-up electromyographic examination confirmed that 1 of the 10 patients had an iatrogenic suprascapular nerve injury, whereas ultrasound evaluation revealed that 2 of 10 repairs failed. Pain relief was achieved in the eight patients with intact repairs and not in the two with recurrent tears. All patients had some limitation of active motion or strength, especially in external rotation. Thus 7 of 10 patients had neither evidence of nerve injury nor recurrent rotator cuff tears yet still showed limited active motion or weakness. It appears that operative injury to the suprascapular nerve during cuff mobilization can occur, but other factors such as inadequate cuff muscle function are more frequently responsible for the poor functional outcomes seen after successful repairs of massive rotator cuff tears. 相似文献
103.
Accuracy in estimating activity duration is one of the key prerequisites for successful construction planning. Efficient material transportation plays an important role in reducing costs and time. Time measurement and work-study techniques can provide good estimation of activity duration, but forming the databank for various conditions is expensive. The use of empirical models has been developed as an alternative to overcome the deficiency while maintaining a reasonable accuracy. In this research traditional linear regression models and nonlinear neural network models have been developed for predicting hoisting times of a tower crane. It is found that nonlinear neural network models can achieve higher accuracy. However, planners may find that the regression models, which describe the relationship between the variables in more simplistic terms, could allow them to shorten the hoisting times by manipulating the input variables. The results and the merits of the models are discussed. 相似文献
104.
Dave Carr Audrey Mendoza 《电子产品世界》2005,(17):88-89
用户对激动人心的全新网络服务的需求,正在推动网络带宽和数据流量的增长.作为回应,网络正在向更有效的以包为基础的模式发展,这种模式使网络能够为用户提供其需要的服务,并开发出额外的收入来源.网络设备制造商必须掌握包处理技术,才能提供新的服务,从而应对不断增加的网络复杂性及适应不同网速的要求. 相似文献
105.
106.
Amy Logan Li Day Audrey Pin Martin Auldist Andrew Leis Amirtha Puvanenthiran Mary Ann Augustin 《Food and Bioprocess Technology》2014,7(11):3175-3185
The size of the casein micelles (CM) and the milk fat globules (MFG) vary depending on farming factors, such as seasonal variation and stage of lactation, and cow genetics. The MFG and CM size of milk can influence the renneting behavior and texture of manufactured dairy products. In this work, we investigated the combined effects of MFG and CM size on the onset of gelation, the maximum rate of gelation, the value for G′60 min (the final storage modulus) and G″60 min (the final loss modulus), and tan δ upon renneting. Fractionation of MFG on the basis of size was carried out using laboratory-based centrifugation, whereas milk of predominantly large (184–218 nm) or small (147–159 nm) CM was selected naturally on-farm. Casein micelle size had the dominant effect on curd firmness and gelation rates of milk, where small CM milk formed rennet gels earlier and resulted in a firmer gel than milk with large CM. However, MFG size also influenced the renneting properties. The strongest rennet gels were obtained when large MFG (3.88–5.78 μm) was combined with small CM (153–159 nm). Selecting milk on the basis of the microstructure of key milk components could be achieved by natural selection of dairy cows or via fractionation technologies. Selection may provide a useful tool for efficient manufacturing of different dairy products based on the desirable characteristics specific to each. 相似文献
107.
J. Szamos Anna Jánosi Boróka Tamás éva Kiss 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1998,206(3):208-212
This paper describes a practical application of the interfacial protein enrichment method, called three-phase partitioning
(TPP), and outlines its significance in the differentiation of multicomponent protein systems, such as homogenates and drips
of different meats (pork, beef, chicken, turkey and wild-boar). The results obtained using the single-protein model system
are also reported to demonstrate the basic process and some characteristic features of TPP. For meat-protein-partitioning
experiments, ammonium sulphate (41% relative saturation) and 23.7% tert-butanol were used at 20 – 25°C. Using this two-liquid system, a characteristic distribution of three phases (including a
semi-solid midlayer) was obtained for homogenates of eight different meats following centrifugation. Compressibility, expressed
as a ratio of layer thickness obtained by low-speed (200 g) and medium-speed (4500 g) centrifugation, allowed us to distinguish between beef and pork drips. A good correlation was
found between layer thickness and storage time for wild-boar samples. The partitioning presented here can be considered as
a rapid and simple method for comparison between raw meat samples of different origin.
Received: 9 July 1997 / Revised version: 1 October 1997 相似文献
108.
Marmosets are widely used, but detailed studies on localisation of endometrial oestrogen receptors alpha and beta (ER alpha and ER beta ), and the progesterone receptor (PR) are lacking. These receptors were localised and semi-quantitatively analysed throughout the ovulatory cycle, weeks 2, 3 and 4 of pregnancy and after treatment with GnRH antagonist, vascular endothelial growth factor (VEGF) Trap or ovariectomy. The PR in epithelial cells increased markedly between the mid- and late proliferative phases before declining in the mid-secretory phase and pregnancy. PR in stromal cells was present throughout the cycle and levels were maintained in pregnancy. ER alpha was present at the mid-proliferative phase and increased in glands at the late proliferative and early secretory phases, before declining at the late secretory phase and week 4 of pregnancy. Stromal ER alpha showed a similar trend, but decreased earlier, by the mid-secretory phase. ER beta was highly expressed in epithelial cells throughout the cycle and in pregnancy. In stroma, increases in ER beta expression were observed at the late proliferative phase with the staining index decreasing by half as the secretory phase progressed and in pregnancy. GnRH antagonist, VEGF Trap or ovariectomy caused significant reductions in PR and ER beta expression, but not in ER alpha when compared with the late proliferative phase of the normal cycle. Endothelial cells expressed ER beta , but not ER alpha or PR. It is concluded that the steroid receptor profile in the marmoset endometrium is generally similar to the human and should provide a useful model for studies on hormonal manipulation of the endometrium. 相似文献
109.
Dantigny P Guilmart A Bensoussan M 《International journal of food microbiology》2005,100(1-3):187-196
For over 20 years, predictive microbiology focused on food-pathogenic bacteria. Few studies concerned modelling fungal development. On one hand, most of food mycologists are not familiar with modelling techniques; on the other hand, people involved in modelling are developing tools dedicated to bacteria. Therefore, there is a tendency to extend the use of models that were developed for bacteria to moulds. However, some mould specificities should be taken into account. The use of specific models for predicting germination and growth of fungi was advocated previously []. This paper provides a short review of fungal modelling studies. 相似文献
110.
Youlong Yu Luenfu Lui Hwayaw Tam Wenghong Chung 《Photonics Technology Letters, IEEE》2001,13(7):702-704
A wavelength-division-multiplexing technique for interrogating 10-cascaded fiber Bragg grating sensing elements based on a ring-compounded-cavity fiber laser is reported. A feedback control technique was introduced to a tunable Fabry-Perot filter that tracks the wavelength-shift of the sensor. The sensors were demodulated using an unbalanced scanning Michelson interferometer and a sensitivity of 1.682°/με has been demonstrated 相似文献