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Ti-6Al-4V alloy is widely used for the deep-sea manned submersible. In addition to the normal cyclic loading, the manned cabin will experience a period of dwell time in each cycle during their service life. In this research, the fatigue and dwell-fatigue crack growth behavior of Ti-6Al-4V alloy under different dwell time were studied experimentally. The mechanism of dwell-fatigue crack growth was investigated. The acceleration phenomenon of the dwell-fatigue crack growth can be directly observed in the experiment. The relationship between the crack length and the dwell time was captured under different $\mathrm{\Delta }K$ within one cycle. The results presented that there is a saturation time for the dwell-fatigue crack growth. A prediction model is proposed to predict the dwell-fatigue crack growth behavior considering the effects of dwell time.

We theoretically investigate dwell time for electrons in a magnetic nanostructure with a $\delta$-doping, which is formed on $\mathrm{\text{InAs}}/{\mathrm{\text{Al}}}_x{\mathrm{\text{In}}}_{1-x}\mathrm{\text{As}}$ heterostructure by depositing a ferromagnetic (FM) stripe. We find that dwell time depends strongly on electron-spins owing to Zeeman coupling and broken symmetry. We also demonstrate that spin-polarized dwell time can be manipulated by $\delta$-doping. Thus, electron spins can be separated in time dimension and such a magnetic nanostructure can be employed as a structurally-controllable temporal spin splitter for spintronics device applications.

Titanium alloy is widely applied in the pressure hull of the manned submersible for its good mechanical properties. The operations of the manned submersible include diving, cruising and ascent. The load spectrum of the pressure hull is a typical dwell-fatigue process. The dwell effect is known to induce a reduction in the fatigue life of titanium alloys at room-temperature. The dwell fatigue of the new titanium alloy is the key issue to ensure a safe submersible operation. In this paper, the dwell-fatigue behavior of a new titanium alloy for pressure hull is investigated. It is found that the accumulated strain at the final rupture increases with the increase of dwell time, and the total cycle decreases. The total cycle life of the specimen decreases, and the accumulated strain increases with increasing peak stress level. The introduction of the dwell time at the peak stress will significantly reduce the dwell-fatigue life and the mechanism is due to the accumulation of the plastic strain.

We study the scattering of a Gaussian wave packet in the modified Pöschl–Teller potential well in time respect. Analytical expressions of average dwell time, phase time, and average traversal time due to Larmor-clock times are obtained, from which the average traversal time can be identified with the average dwell time. We observe that the average dwell time is appreciably longer than the phase time at low energies, but they tend to coincide in the limit of narrow momentum distribution, high energy, and large interaction region. We also find that both of them are longer than the classical scattering time in the potential. All of these times are, however, shorter than the free-particle time, demonstrating the acceleration effect of the potential in temporal aspect of the scattering.

In this paper, single crystalline 1D tetragonal MnO₂ pen-type nanorods were synthesized by varying the dwell time through a facile hydrothermal route at a reaction temperature of 250°C. X-ray diffraction (XRD) and transmission electron microscopy (TEM) studies showed that the diameter of MnO₂ nanorods decreases from 460 nm to 250 nm with the increase in hydrothermal reaction time from 5 h to 15 h. Field-emission scanning electron microscopy (FESEM) and TEM studies revealed the evolution of improved surface morphology of MnO₂ nanorods that are prepared with longer hydrothermal reaction time. The magnetic properties of the products were evaluated using vibrating sample magnetometer (VSM) at room temperature, which showed that the as-prepared samples exhibit weak ferromagnetic behavior. The effect of diameter on the magnetization values was observed and discussed in detail.

In the field of printed electronics, there are many kinds of ink with a variety of performance and parameters. In order to generate high-quality droplets, it is necessary to eject droplet for testing in order to discover the appropriate excitation voltage and waveform shape. Consequently, a real-time and efficient droplet monitoring system is needed to monitor droplet formation quality. A multi-satellite droplet monitoring system is proposed in this paper. It can not only monitor the droplet with multiple satellites but also can generate the instantaneous droplet position curve, length curve and velocity curve. The waveform voltage and dwell time can be adjusted in real-time to obtain droplets with higher quality and efficiency.

Calendaring is an important operation in pulp and paper mill, with an objective to increase the smoothness or reduce the roughness of paper. Bypassing calendering operation in paper machine, paper of desired quality cannot be produced. In the present investigation, a nip mechanics model for supercalendering has been developed by expanding Meijers nip mechanics model up to fourth term, and using this model the effect of additional fourth term and various design and process parameters on results of supercalendering has been discussed using the data taken from paper industry.

The electron tunneling in ZnO/ZnCdO semiconductor heterostructure is studied using the matrix method. The spin-polarization is examined due to Dresselhaus spin–orbit interaction and Rashba spin–orbit interaction. The total spin-polarization is mainly due to Dresselhaus spin–orbit interaction and the Rashba spin–orbit interaction is small. The high degree of spin polarization can be achieved at a high barrier width. With the increasing cadmium concentration in this heterostructure, the spin polarization efficiency is enhanced. The dwell time is reported and discussed.

The effect of in-plane wave vectors on spin-dependent transport properties is examined theoretically. In this work, ZnO/Zn${}_{1-x}$Cd_xO double barrier-heterostructure with an identical barrier width of 30 Å is considered. The transmission coefficient is calculated by using the transfer matrix. The role of Dresselhaus spin–orbit coupling is accounted. The in-plane wave vector influences the energy separation between different orientations of the electrons. The spin separation ranges from 0.002meV to 0.008meV as the in-plane wave vector changes from $1\times 10^8$/m to $5\times 10^8$/m. The degree of spin polarization is enhanced at the high magnitude of the in-plane wave vector. The dwell time of the incident electrons is examined. The role of heterostructure strain on spin-transport properties is also reported. About 73% of polarization efficiency is observed in this study when the heterostructure strain is observed.