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In this paper, an axisymmetric rotor of a 1000-MW ultra-supercritical steam turbine was modeled with the commercial finite-element software ABAQUS with inlet parameters of 35 Mpa and 600°C. The temperature and Mises stress distributions of the rotor during the start-up procedure were then analyzed. The fatigue damage was predicted by the strain-life–based Manson-Coffin equation and the Miner rule. The results demonstrated that the fatigue damage was mainly generated at the rotor surface. For the requirement of the half life time, the cyclic number almost reached 4000. Furthermore, optimization by extending the warm-up phase is proposed to eliminate strain fluctuations and further decrease fatigue damage. The results showed that the fatigue damage significantly decreased at four key locations. The fatigue life during the start-up phase was improved.

Objective. The aim of this study was to evaluate the effect of gentle tactile stimulation on the fetus in its temperament 3 months after birth. Method. A total of 302 mother-3-month-infant dyads enrolled the retrospective cohort study. 76 mothers had regular gentle tactile stimulation on the fetus in their pregnancy; 62 mothers had irregular tactile stimulation on the fetus, and the rest of 164 mothers who had no tactile stimulation served as nonexposure group. Temperament was assessed using the EITS (a nine-dimensional scale of temperament). Results. Significant difference in temperament type was found among infants in 3 groups at 3 months of age. In the regular practice group, the babies with easy type temperament accounted for 73.7%, which was higher than that in irregular practice group (53.2%, P = 0.012 ) and that in the control group (42.1%, P < 0.001 ). Compared to infants in no practice group, the infants who had received regular gentle tactile stimulation before birth were lower in negative mood ( P = 0.047 ) while higher in adaptability ( P < 0.001 ), approach ( P = 0.001 ), and persistence ( P = 0.001 ), respectively. Conclusion. Regular gentle tactile stimulation on fetus may promote the formation of easy type infant temperament.

Due to increasing environmental concerns, natural resource use must become more efficient. As a result, green design is now an important research topic. The goal of this study was to create a green modular design method using the concept of chemical activation energy. The method uses five product functions and five product attributes that affect green performance to group parts into functional modules and then group parts into green modules within each functional module. Considering both product functions and environmental factors ensures the functional feasibility of the modules that are created and also improves the green performance of the product. The method developed in this study was used to group parts into functional modules and green modules for an LCD monitor. The study results can be used to help designers create new green products or improve the green performance of existing products.

Exploring the mechanical properties and thermal cracking characteristics of rock under thermo-hydro-mechanical coupling in detail is of great importance for the safe excavation and stability of deep rock engineering. The mechanical properties and thermal cracking characteristics of granite under burial depths of 1000 m (confining pressure of 25 MPa) and 1600 m (confining pressure of 40 MPa) at a temperature of 110?C and a pore water pressure of 10 MPa were studied. The results show that the elastic modulus decreases with increasing temperature under a confining pressure of 25 MPa, whereas under a confining pressure of 40 MPa, the elastic modulus increases with increasing temperature. As the pore water pressure increases, the elastic modulus decreases slightly. Poisson?s ratio increas?es with increasing temperature below 40?C but decreases from 50-110?C. Pois?son?s ratio increases as pore water pressure increases. During the heating process, acoustic emission activity is first detected at 30-40?C and is relatively stable from 40-90?C. The acoustic emission activity increases sharply at 90-110?C, and the thermal cracking threshold of granite under thermo-hydro-mechanical coupling is approximately 95?C.

Impatiens walleriana ( I. walleriana ), a potential cadmium (Cd) hyperaccumulator, can propagate by cuttings, which are less expensive to grow than seedlings. Different growth periods for cuttings, however, may lead to different physiological characteristics. In this study, I. walleriana cuttings were hydroponically grown in Cd-containing solutions (1.0–10.0 μM) for various growth periods (10–60 days). Experimental results showed that the Cd treatments had negative effects on growth compared to the controls that were not spiked with Cd. The extension of the growth period promoted most of the growth exhibitions of I. walleriana , except for SPAD readings for cuttings grown in the 5.0 and 10.0 μM solutions. The accumulation of Cd also increased over time, except in the roots of the cuttings grown in the 5.0 and 10.0 μM solutions. The subcellular distribution and chemical forms of Cd showed that I. walleriana developed better tolerance and detoxification capacities in the cuttings grown in the 5.0 and 10.0 μM solutions than in the cuttings grown in the other two Cd treatments.

In the present study, hemodynamics of the internal carotid artery-posterior communicating artery (ICA-PComA) was numerically modeled with CFD approach. The steady and pulsating blood flow in the ICA-PComA was simulated. The main concern was placed on the influence of aneurysm geometry on the local hemodynamics by changing the sac diameter and Aspect Ratio (AR) of the aneurysm. The numerical results show the significantly weakened Wall Shear Stress (WSS) and the intensified wall pressure in the aneurysm as AR is increased. Two factors, i.e., low WSS and high pressure of the aneurysm, may play important roles in the fragile change of the aneurysm and the final rupture. The distributions of Time-Averaged WSS (TAWSS), Oscillatory Shear Index (OSI) and spatial WSS Gradients (WSSG)) were determined and discussed in view of their influences on the evolution of ICA-PComA aneurysm.

The leakage flow through two labyrinth seals, e.g the interlocking seal and the stepped seal, was numerically investigated. Preliminary calculation of the seal-cavity averaged pressure by using the one-dimensional control volume method showed favorable agreement with the experimental measurements. Subsequently, in-depth understanding of the fluid flow through the labyrinth seals was obtained by employing Computational Fluid Dynamics (CFD) and k-ε turbulence model, which resulted in a potential wealth of information like the streamline pattern, velocity vector field, and distribution of turbulent kinetic energy and static pressure. At the clearance of the seal the turbulent kinetic energy reached the peak value, while in the bulk region of the cavities it decayed fast. The static pressure rapidly dropped as the fluid flow went through the clearance; no distinct difference of the static pressure was inspected in the cavities. Also noted from the numerical results was that the stepped seal showed better sealing performance than the interlocking seal

An improved phase averaging method based on cross-correlation of the instantaneous velocity field determined by TR-PIV measurements is proposed in this article. A Time-Resolved Particle Image Velocimetry (TR-PIV) is used to measure the two-dimensional wake behind the square cylinder. The phase signals associated with the deterministic appearance of the Karman vortex street are obtained by calculating the correlation matrix of the low-pass filtered velocity field, and can provide the complete information of the phase-averaged wake flow. The results show the advantages of the enhanced methodology in extracting the quasi-periodic flow patterns related to the shedding coherent structures without using additional reference signals.

A collaborative investigation of two-fluid mixing in a swirl micro-mixer was carried out by the Shanghai Jiao Tong University and the Tokyo Denki University. Pure water and a mixture of glycerol and water were separately injected into branch channels and they were subsequently mixed in the central chamber. The two-fluid flow pattern was numerically modeled, in which the dependence of the mixture viscosity and density on the mass fraction of glycerol in the mixing fluid was carefully taken into consideration. The mixing performance of the two fluids was evaluated by varying the Reynolds numbers and the mass fractions of glycerol in water. The mixing process was extensively analyzed using streamline maps and contour plotting distributions of pressure and glycerol concentration. The numerical results show that the acceptable uniformity of mixing at Re = 0.1 is primarily attributed to the time-consuming molecular diffusion, whereas the cost-effective mixing at Re > 500 was obtained because of the generation of the swirling flow. The increasing mass fraction of glycerol in water was found to attenuate the mixing performance. The preliminary microscopic visualization of the two-fluid mixing at Re=1300 demonstrated the consistence with the numerical results.

Insulin is widely used in treating diabetes, but still needs to be administered by needle injection. This study investigated a new needle-free approach for insulin delivery. A portable powder needleless injection (PNI) device with an automatic mechanical unit was designed. Its efficiency in delivering insulin was evaluated in alloxan-induced diabetic rabbits. The skin irritation caused by the device was investigated and the results were analyzed in relation to aerodynamic parameters. Inorganic salt-carried insulin powders had hypoglycemic effects, while raw insulin powders were not effective when delivered by PNI, indicating that salt carriers play an important role in the delivery of insulin via PNI. The relative delivery efficiency of phosphate-carried insulin powder using the PNI device was 72.25%. A safety assessment test showed that three key factors (gas pressure, cylinder volume, and nozzle distance) were related to the amount of skin irritation caused by the PNI device. Optimized injection conditions caused minimal skin lesions and are safe to use in practice. The results suggest that PNI has promising prospects as a novel technology for delivering insulin and other biological drugs.