Hydrothermal Synthesis and Crystal Structure of a One-dimensional Manganese(Ⅱ) Compound Bridged by 2,6-Dichlorobenzoic Acid and Water

A novel manganese（Ⅱ） coordination polymer [Mn（L^1）2（H2O）]·2H2O （HL^1 = 2,6- dichlorobenzoic acid） 1 has been synthesized and structurally characterized. X-ray diffraction analyses reveal that 1 is a one-dimensional chain structure bridged by water molecules and 2,6- dichlorobenzoic acid. The crystal is of monoclinic, space group P21/c with α = 12.9701（19）, b = 20.592（3）, c = 7.3759（10） A, β = 102.660（2）°, V = 1.9221（5）. nm^3, Z = 4, C14H12Cl4MnO7, Mr= 488.98, Dc= 1.690 g/cm^3, p = 1.275 mm^-1, F（000） = 980, Rint = 0.0348, R = 0.0350, and wR = 0.0755. In the crystal the manganese atom is six-coordinated by two oxygen atoms from water and four oxygen atoms from four 2,6-dichlorobenzolate molecules, completing an octahedral geometry.

Syntheses,Crystal Structure and Thermal Analyses of the Complex of Copper(Ⅱ) with N,N'-Bis-Sal icy1idene-Ethyl enediamine(H_2Salen)

Introduction In recent years, the syntheses, properties and applications of the complexes of transition-metal ions with Schiff bases have been a very interesting subject in coordination chemistry. It has been clearly stated that some of them have certain antitumor

Thermal Activation Analyses of Dynamic FractureToughness of High Strength Low Alloy Steels

A formula is derived for determining the influence of temperature and loading rate on dynamic fracture toughness of a high strength low alloy steel (HQ785C) from thermal activation analysis of the experimental results of three-point bend specimens as well as introducing an Arrhenius formula. It is shown that the results obtained by the given formula are in good agreement with the experimental ones in the thermal activation region. The present method is also valuable to describe the relationship between dynamic fracture toughness and temperature and loading rate of other high strength low alloy steels.

Design, Analysis and R&D of the EAST In-Vessel Components

In-vessel components are important parts of the EAST superconducting tokamak. They include the plasma facing components, passive plates, cryo-pumps, in-vessel coils, etc. The structural design, analysis and related R＆D have been completed. The divertor is designed in an up-down symmetric configuration to accommodate both double null and single null plasma operation. Passive plates are used for plasma movement control. In-vessel coils are used for the active control of plasma vertical movements. Each cryo-pump can provide an approximately 45 m^3/s pumping rate at a pressure of 10^-1 Pa for particle exhaust. Analysis shows that, when a plasma current of 1 MA disrupts in 3 ms, the EM loads caused by the eddy current and the halo current in a vertical displacement event （VDE） will not generate an unacceptable stress on the divertor structure. The bolted divertor thermal structure with an active cooling system can sustain a load of 2 MW/m^2 up to a 60 s operation if the plasma facing surface temperature is limited to 1500 ℃. Thermal testing and structural optimization testing were conducted to demonstrate the analysis results.

Role of viscous heating in entransy analyses of convective heat transfer

The entransy theory is widely used and found to be effective in thermal analyses and optimizations.Some researchers considered the entransy variation due to viscous heating as part of entransy dissipation and analyzed convective heat transfer based on the differential relationship between entropy and entransy.However,it has been pointed out that the derivation of the differential relationship between entropy and entransy is incorrect.In this paper,the convective heat transfer processes with viscous heating is reconsidered and analyzed from the viewpoint of the energy conservation and the entransy balance equation.It is shown that the influence of the viscous heating is equivalent to that of an inner heat source.Therefore,the contribution of viscous heating to system entransy should not be treated as part of entransy dissipation,but entransy flow into the system.Two-stream parallel and counter flow heat exchangers with viscous heating and a thermal insulation transportation problem of heavy oil are taken as examples to verify the theoretical analyses intuitively.In the examples,the numerical results show that the entransy dissipation rates could be negative when the influence of the viscous heating on the system entransy is treated as part of the entransy dissipation.This is obviously unreasonable.Meanwhile,when the entransy contribution from the viscous heating to the system entransy is treated as entransy flow into the system,it is shown that the entransy dissipation rate is always positive,and the heat transfer processes can be well explained with the entransy theory.