Effects of the computational domain on the secondary flow in turbulent plane Couette flow

A series of direct numerical simulations of the fully developed plane Couette flow at a Reynolds number of 6000（based on the relative wall speed and half the channel height h） with different streamwise and spanwise lengths are conducted to investigate the effects of the computational box sizes on the secondary flow（SF）. Our focuses are the number of counter-rotating vortex pairs and its relationship to the statistics of the mean flow and the SF in the small and moderate computational box sizes. Our results show that the number of vortex pairs is sensitive to the computational box size, and so are the slope parameter, the rate of the turbulent kinetic energy contributed by the SF, and the ratio of the kinetic energy of the SF to the total kinetic energy. However, the averaged spanwise width of each counter-rotating vortex pair in the plane Couette flow is found, for the first time, within 4（1 ± 0.25）h despite the domain sizes.

THE SECONDARY REACTION IN THE CONDENSATION OF 1-METHYL-2-METHYLTHIO-IMIDAZOLINE WITH ACTIVE METHYLENE COMPOUNDS

Mono-substituted heterocyclic ketene aminals are formed by the reaction of 1-methyl-2-methylthio-imidazoline with active methylene compounds containinq an acetyl or benzoyl group by the elimination of both a methylthio and an acyl group.This is resulted by the secondary reactio of the produced methanethiol to attack the more active carbonyl group.

Waging a Struggle from Dilemma-Implementing the Secondary Stage of Pioneering

The Tianjin Light Industrial Products Import & Export Corporation was founded in 1953. It is an old enterprise with a long history and large scale, handling import and export business in northern China. Over the four decades, the corporation has got numerous export earnings for the state by constantly developing its overseas market, opening export channels, increasing varieties and specifications and improving the quality of commodities. It has boosted the development of domestic production enterprises for light industrial products and has achieved brilliant successes.

The Magic Appeal： Fantasy Elements in the Twilight Series

The Twilight series by Stephanie Meyer, including Twilight, New Moon, Eclipse, and Breaking Dawn, has won multiple awards and is the most popular among young adults. The series is both an unbelievable romance of a 17-year-old girl and a 104-year-old vampire and an exquisite fantasy of the supernatural and impossible. Typical fantasy elements exploited in the series, including the existence of supernatural creatures, fulfillment of human desires, depiction of the Secondary World, and imagination of a Utopian society, play a significant role in achieving its magic appeal to the readers worldwide. Thus, the present paper attempts to explore how such irresistible attraction is made possible by employing these fantasy elements.

On the Criminal Protection of the Right to Education of Chinese Citizens——With a Review on Article 32 of the Amendment to the Criminal Law(Ⅺ)

The Amendment(Ⅺ)to the Criminal Law of the People’s Republic of China responds to the institutional needs of civic education,and supplements the clause of the Criminal Law on protection of citizens’right to education nuy means of Article 32.Imposing legal responsibility in the form of internal punishments,administrative punishments,and economic compensation have failed to prevent infringements on citizens’right to education.Its role as a"secondary protection law"is the conceptual obstacle that hinders the Criminal Law from effectively intervening in the field of citizens’right to education.The equivalence between the legal interests of people to the right to education and the rights protected by the existing charges in the Criminal Law is the legitimate basis for it to intervene in disputes over the right to education.Based on Article 32 of the Amendment(Ⅺ)to the Criminal Law of the People’s Republic of China,it is suggested to further clarify the prepositional law,improve the liability provisions for the right to education,change the modest and restrained view of the Criminal Law regarding protection of the right to education,and expand the behavior types of Article 32 provided in the Amendment(Ⅺ)in due time.

Determination of the spin parameter and the inclination angle from the primary and secondary images caused by gravitational lensing

We study the primary images(PIs)and secondary images(SIs)caused by strong gravitational lensing around a Kerr black hole shadow,which carry some essential signatures related to the black hole space-time.We define a new celestial coordinate,whose origin is the center of the black hole shadow,to locate the PIs and SIs of luminous celestial objects.Based on the dragging effect caused by the rotating black hole and the inclination angle of the observer,the relative positions between the PIs and SIs are different for different values of the Kerr spin parameter a and the observer's inclination angle i;hence,it can be used to determine the values of a and i.We propose a specific approach to measure a and i using the PIs and SIs.The time delays between the PIs and SIs are different for different values of a and i.The time delays,in conjunction with the relative positions between the PIs and SIs,can enable us to measure a and i more precisely.These PIs and SIs around the black hole shadow act as unique fingerprints for the black hole space-time,using which we can further determine other parameters of different types of compact objects and verify various theories of gravity.Our results provide a new method to implement parameter estimation in the study of black hole physics and astrophysics.

Identification and Profiling of Known and Novel Fiber MicroRNAs during the Secondary Wall Thickening Stage in Cotton(Gossypium hirsutum) via High-Throughput Sequencing

Upland cotton （Gossypium hirsutum L.） is an allotetraploid species originated from interspecific hybridization between AA-genome diploid （G. arboretum） and DD-genome diploid （G. raimondii） （Wendel et al., 1992）. Cotton fibers are single-celled trichomes that emerge from the ovule epidermal cells. Indexed by the number of days post-anthesis （dpa）, fiber morphogenesis includes four distinct but overlapping steps： initiation （0-3 dpa）, elongation （3-20 dpa）, secondary cell wall thickening （15-45 dpa） and maturation （40-60 dpa） （Yang et al., 2008, Du et al., 2013）. The efficiency and duration of each morphogenesis stage is important to the quality attributes of the mature fiber. Cell elongation is critical for fiber length, whereas secondary cell wall thickening is important for fiber fineness and strength （Meinert and Delmer, 1977）.

Study on effects of the secondary fuel manifold unfold pressure on engine starting performance

The fuel manifold is an import accessory through which the fuel enters in combustor,after measuring in fuel control system.The component test results of fuel manifolds show that,when the starting fuel supply is given and the primary fuel manifold relative unfold pressure is at constant,the adjustment of the secondary fuel manifold turn-on pressure has effects on fuel flow through the secondary fuel manifold and the time of fuel into the combustion chamber.The verification test of the secondary fuel manifold unfold pressure influence on engine starting performance has been conducted,showing that the unfold pressure variation of the secondary fuel manifold has great influence on the engine start performance.The test research results have important guidance and reference meaning for confirming the secondary fuel manifold unfolds pressure.

EFFECT OF THE THERMAL FORCING ON THE SECONDARY CIRCULATION OF TYPHOONS

A non-dimensional secondary circulation equation for typhoons has been derived and then 11-yr com- positing typhoon data were used to estimate the thermally forced secondary circulation.The main results have been obtained as follows: (1)The diabatic heating and Cu vertical heat mixing are major thermal forcing factors.They have the same magnitude of order.(2)The effects of eddy flux and Cu horizontal mixing of heat are of minor im- portance.(3)Ekman pumping and Cu vertical heat mixing cooperatively work.This feedback process is favorable for the enhancement of the secondary circulation of typhoons.

he Design of Efficient Heat Transfer Based on Flat Plate Solar Water Heater

This is an improved design based on the existing plate type solar water heaters. It aims at making full use of solar energy. To fully absorb radiation, it absorbs coating selectively by adopting the magnetron sputtering technology AL-N/AL. this design conduct heat through aluminum material which can reduce the cost meanwhile conduct heat effectively. To ensure the quality of the water at the same time improve the utilization rate of solar energy, this design use phase change for second heat exchange. Take Shanghai for example, where this design and heat transfer model are applied, the average efficiency of water heaters can achieve 68%, which has proven the feasibility of the design. In a word, this design can achieve the goal of energy conservation and emissions reduction and has broad market prospects.

Research on Flow and Heat Transfer Characteristics Inside Spiral Pile-honeycomb Structures with Different Shapes

Spiral plate heat exchanger is a traditional compact heat exchanger,and widely used in the occasion of the high heat transfer capacity requirements,such as waste heat recovery. In the situation of energy shortage and rapid development of heat transfer technology^([1-3]),cylindrical,elliptical and rhombic spiral pile-honeycomb heat transfer models are established^([4-5]). The internal flow and heat transfer are simulated by using CFD software FLUENT15. 0 and RNG k-ε turbulent model,and then the three models are analyzed. The results show that the secondary flow and vortex are induced again in the secondary honeycomb,which further increases the turbulence intensity of the fluid. The thickness of the boundary layer is reduced twice,and the heat transfer effect is better than that of the honeycomb spiral structure. The spiral pile-honeycomb model for the rhombus is better than the models of cylinder and ellipse in heat transfer performance.