Productive Traits and Triploid Rate Stability in Triploidy-Induced ‘Haida No. 2’ Strain of the Pacific Oyster, Crassostrea gigas

In order to evaluate the effects of triploidy induction on a selected strain‘Haida No.2’of the Pacific oyster Crassostrea gigas,which is characterized with golden shell color and high growth rate,the growth,survival rate and stability of triploid rate were analyzed at different development stages in the present study.Three different conditions inhibiting the release of polar body Ⅱ or polar body Ⅰ were tested:(A)Cytochalasin-B(CB),0.5mg L^(−1) at 10min post-insemination for 15 min;(B)CB,0.5mg L^(−1)at 15 min postinsemination for 20 min;and(C)CB,0.7mg L^(−1),at 15 min post-insemination for 20 min.The triploidy induction treatments significantly reduced the D-larvae and survival rates at the larvae stage but not at the juvenile and adult stages.Triploid rate dramatically decreased at the larval stage and did not significantly change at the juvenile and adult stages.Regarding the stability of the triploid rate,there was a significant difference between the three treatment groups.Larvae from the treatment A and control groups exhibited higher growth rates in shell height than those from the other two treatment groups at day 27.Triploid juveniles and adults from the treatment A group exhibited a higher wet weight than diploids from the control group and triploids from the other treatment groups.Triploidy induction did not affect the shell color of the progeny.The results obtained in the study demonstrate that triploidy induction has the potential to be used to increase the production of C.gigas variety‘Haida No.2’without modifying its golden shell color.

Effect of varying normal stress on stability and dynamic motion of a spring-slider system with rate- and state-dependent friction

Incorporating rate and state friction laws, stability of linearly stable （i.e., with stiffness greater than the critical value） spring-slider systems subjected to triggering perturbations was analyzed under variable normal stress condition, and comparison was made between our results and that of fixed normal stress cases revealed in previous studies. For systems associated with the slip law, the critical mag- nitude of rate steps for triggering unstable slips are found to have a similar pattern to the fixed normal stress case, and the critical velocity steps scale with a/（b - a） when k = kcr for both cases. The rate-step boundaries for the variable normal stress cases are revealed to be lower than the fixed normal stress case by 7 %-16 % for a relatively large ct = 0.56 with （b - a）/a ranging from 0.25 to 1, indicating easier triggering under the variable normal stress condition with rate steps. The difference between fixed and variable normal stress cases decreases when the α value is smaller. In the same slip- law-type systems, critical displacements to trigger instability are revealed to be little affected by the variable normal stress condition. When k 〉 kcr（V,）, a spring-slider system with the slowness law is much more stable than with the slip law,suggesting that the slowness law fits experimental data better when a single state variable is adopted. In stick-slip motions, the variable normal stress case has larger stress drops than the constant normal stress case. The variable normal stress has little effect on the range of slip velocity in systems associated with the slowness law, whereas systems associated with the slip law have a slowest slip velocity immensely smaller than the fixed normal stress case, by ~ 10 orders of magnitude.

Enhanced Anion-Derived Inorganic-Dominated Solid Electrolyte Interphases for High-Rate and Stable Sodium Storage

It is highly desirable for the promising sodium storage possessing high rate and long stable capability,which are mainly hindered by the unstable yet conventional solvent-derived organic-rich solid electrolyte interphases.Herein,an electrolyte solvation chemistry is elaborately manipulated to produce an enhanced anion-derived and inorganic components-dominated solid electrolyte interphases by introducing a low permittivity(4.33)bis(2,2,2-trifluoroethyl)ether diluent into the sodium bis(trifluoromethylsulfonyl)imidedimethoxyethane-based high concentration electrolyte to obtain a localized high concentration electrolyte.The bis(2,2,2-trifluoroethyl)ether breaks the balance of original cation solvation structure and tends to interact with Na^(+)-coordinated dimethoxyethane solvent rather than Na^(+)in high concentration electrolyte,leaving an enhanced Coulombic interaction between Na^(+)and(FSO_(2))_(2)N^(-),and more(FSO_(2))_(2)N^(-)can enter the Na^(+)solvation shell,forming a further increased number of Na^(+)-(FSO_(2))_(2)N^(-)-dimethoxyethane clusters(from 82.0%for high concentration electrolyte to 94.3%for localized high concentration electrolyte)at a low salt dosage.The preferential reduction of this(FSO_(2))_(2)N^(-)-enriched clusters rather than the dimethoxyethane-dominated Na^(+)solvation structure produces an enhanced anion-derived and inorganic components-dominated solid electrolyte interphases.The reversible charge storage process of Na is decoupled by operando Raman along with a shift of D and G peaks.Benefiting from the enhanced anion-derived electrode-electrolyte interface,the commercial hard carbon anode in localized high concentration electrolyte shows a well rate capability(5 A g^(−1),70 mAh g^(−1)),cycle performance and stability(85%of initial capacity after 700 cycles)in comparison to that of high concentration electrolyte(68%)and low concentration electrolyte(only 5%after 400 cycles),indicative of uniqueness and superiorities towards stable Na storage.

Research on Emulsion Stability and Solubility of Polymer Drag Reducer

In oilfield fracturing construction, to solve the technical problems such as poor dissolution effect and long dissolution time of polymer drag reducer powder, the rheological regulator, phase transfer agent, organic solvent, and drag reducer powder were compounded to prepare a drag reducer emulsion that was soluble in water. The stability of the drag reducer emulsion was observed at room temperature for 90 days. The effects of the rheological regulator, phase transfer agent, and organic solvent on the stability and solubility of the drag reducer emulsion were studied. The dissolution time, dissolution effect, viscosity of the aqueous solution, and drag reduction performance of the drag reducer emulsion were evaluated. The results show the stability rate of the drag reducer emulsion prepared by MOST-1 rheological regulator, BHJ-8 and BHJ-6 compound phase inversion agent, ethylene glycol ether and 120 - 140 mesh powder can reach 97% at room temperature for 90 days. Compared with the drag reducer powder, when the aqueous solution concentration is 0.1%, the dissolution time is only 28 s, the viscosity can be increased by 30%, and the drag reduction rate can be increased by up to 8%.

Exchange Rate Instability: Japan's Micro-Macro Experiences and Implications for China

Since 1985, the yen-dollar exchange rates repeatedly fluctuated and climbed to a level that could not be justified by economic fundamentals. The impacts on the Japanese economy were serious and far-reaching. Since 21 July 2005, China has been moving toward a more flexible exchange rate regime. Keeping RMB exchange rates basically stable and providing Chinese industries with means to hedge exchange rate risks are essential for China＇s sound economic development.

ACTIVE FRONT STEERING DURING BRAKING PROCESS

An active front steering （AFS） intervention control during braking for vehicle stability is presented. Based on the investigation of AFS mechanism, a simplified model of steering system is established and integrated with vehicle model. Then the AFS control on vehicle handling dynamics during braking is designed. Due to the difficulties associated with the sideslip angle measurement of vehicle, a state observer is designed to provide real time estimation. Thereafter, the controller with the feedback of both sideslip and yaw angle is implemented. To evaluate the system control, the proposed AFS controlled vehicle has been tested in the Hardware-in-the-loop-simulation （HILS） system and compared with that of conventional vehicle. Results show that AFS can improve vehicle lateral stability effectively without reducing the braking performance.

China's Exchange Rate and Financial Repression:The Conflicted Emergence of the RMB as an International Currency

Instability in the worm dollar standard, as most recently manifested in the US Federal Reserve＇s near-zero interest rate policy, has caused consternation in emerging markets with naturally higher interest rates. China has been provoked into speeding RMB ＂internationalization ＂; that is, opening up domestic financial markets to reduce its dependence on the US dollar for invoicing trade and making international payments. However, despite rapid percentage growth in offshore financial markets in RMB, the Chinese authorities are essentially trapped into maintaining exchange controls （reinforced by financial repression in domestic interest rates） to avoid an avalanche of foreign capital inflows that would threaten inflation and asset price bubbles by driving nominal interest rates on RMB assets down further. Because a floating （appreciating） exchange rate could attract even more hot money inflows, the People＇s Bank of China should focus on keeping the yuan/dollar rate stable so as to encourage naturally high wage increases to help balance China ＂s international competitiveness. However, further internationalization of the RMB, as with the proposed Shanghai pilot free trade zone, is best deferred until world interest rates rise to more normal levels.

Extensive experimental investigation of the effect of drainage height and solvent type on the stabilized drainage rate in vapour extraction (VAPEX) process

The low cost of the injected solvent,which can be also recovered and recycled,and the applicability of VAPEX technique in thin reservoirs are among the main advantages of VAPEX process compared to thermal heavy oil recovery techniques.In this research,an extensive experimental investigation is carried out to first evaluate the technical feasibility of utilization of various solvents for VAPEX process.Then the effect of drainage height on the stabilized drainage rate in VAPEX process was studied by conducting series of experiments in two large-scale 2D VAPEX models of 24.5 cm and 47.5 cm heights.Both models were packed with low permeability Ottawa sand(#530)and saturated with a heavy oil sample from Saskatchewan heavy oil reservoirs with viscosity of 5650 mPa s.Propane,butane,methane,carbon dioxide,propane/carbon dioxide(70%/30%)and propane/methane(70%/30%)were considered as respective solvents for the experiments,and a total of twelve VAPEX tests were carried out.Moreover,separate experiments were carried out at the end of each VAPEX experiment to measure the asphaltene precipitation at various locations of the VAPEX models.It was found that injecting propane would result in the highest drainage rate and oil recovery factor.Further analysis of results showed stabilized drainage rate significantly increased in the larger physical model.

Dynamics of a Predator-Prey Ecological System with Nonlinear Harvesting Rate

In this paper, a predator-prey ecological economic system with nonlinear harvesting rate is formulated and studied. This system is described by a differential-algebraic equation. By employing local parameterization method, an equivalent differen- tial system with parameter is obtained. Then by normal form the-ory and bifurcation theory, the complex dynamics of the system are investigated, including the local stability of equilibrium point and Hopf bifurcation. Finally, MATLAB simulation illustrates the effectiveness of our results.

On the Fluid Approximation for a Multiclass Queue under Non-Preemptive SBP Service Discipline

A multi-class single server queue under non-preemptive static buffer priority （SBP） service discipline is considered in this paper. Using a bounding technique, we obtain the fluid approximation for the queue length and busy time processes. Furthermore, we prove that the convergence rate of the fluid approximation for the queue length and busy time processes is exponential for large N. Additionally, a sufficient condition for stability is obtained.