Lithium bromide catalyzed solvent free method for synthesis of 2-substituted benzimidazoles and imidazopyridines

The first successful lithium bromide mediated solvent free condensation of arylenediamine and esters to obtain 2-substituted benzimidazole and imidazopyridine in good to excellent yields is described.

Surface tension of lithium bromide aqueous solution/ammonia with additives and nano-particles

In order to investigate the effect of additives and nano-particle on the surface tensions of lithium bromide(Li Br) aqueous solution/ammonia, many experiments were carried out based on Wilhelmy plate method. Firstly, the surface tension of Li Br aqueous solution with 1-octanol was measured and then the comparison between the measured results and previous experimental results was given to verify the measuring accuracy. Some new additives, such as cationic surfactants cetyltrimethyl ammonium chloride(CTAC), and cetyltrimethyl ammonium bromide(CTAB) were chosen in the experiments. The experimental results show that CTAC and CTAB can obviously reduce the surface tension of Li Br aqueous solution/ammonia. In addition, it is found that nano-particles cannot remarkably decrease the surface tension of Li Br aqueous solution/ammonia. However, the mixed addition of additives and nano-particles can remarkably affect the surface tension of Li Br aqueous solution/ammonia. That is to say, additives play more important role in reducing the surface tension of Li Br aqueous solution/ammonia. But nano-particles may enhance the heat transfer in the absorption refrigeration process.

Studies on Systems of Lithium and Potassium Halides from Salt Lake and Bittern Resources（V）──The Quaternary Reciprocal System Li￣＋■Br￣－，I￣－－H＿2O and Boundary Ternary System NH＿4Br－NH＿4I－H＿2O at 25℃

he solubilities , refractive indexes of saturated solutions of the quaternary re-ciprocal system Li￣+ , Br￣(-) ,I￣(-)H_(2)O and its boundary ternary system NH_(4)Br-NH_(4)I-H_(2)O at 25℃ have been investigated using isothermal method. In the titleternary system which belongs to Roozeboom Ⅳ type, there are two limited solid so-lutions. Entering into the quaternary system, the region of the solid solutions re-duces and disappears with the increase of Li￣+ , and finally, the quaternary systembecomes a simple system.

Anticorrosion Performance of Carbon Steel in 55% LiBr Solution Containing PMA/SbBr_3 Inhibitor

The anticorrosion performance of carbon steel in 55 % LiBr solution containing PMA/SbBr3 inhibitor was studied by weight-loss tests, electrochemical measurements and surface analysis. In 55 %LiBr＋PMA/SbBr3 solution, corrosion rates of carbon steel at 145 ℃, 175℃, 190℃ and 240℃ are 18.32μm·a^-1 , 27.68μm·a^-1, 53.58μm·a^-1 and 73. 78μm·a^-1 , respectively. PMA/SbBr3 inhibitor may inhibit the corrosion of carbon steel in 55% LiBr solution effectively. Especially, it shows an excellent corrosion inhibition performance at high temperature. Both anodic and cathodic reactions of carbon steel may be inhibited by PMA/SbBr3 inhibitor, so it may be classified as mixed inhibitor. In 55%LiBr＋PMA/SbBr3 solution, the apparent activation energy of the corrosion reaction of carbon steel is 29. 61 kJ·mol^-1. The corrosion inhibition mechanism of PMA/SbBr3 is suggested as follows： PMA has the effect of inhibiting hydrogen evolution and a strong oxidizing property; Sb^3＋ also exhibits oxidizing properties, and can exist stably with PMA in LiBr solutions; the passive film comprising Fe2O3 and antimony formed on carbon steel surface may prevent Brfrom diffusing into the metal surface due to the synergistic effect of PMA and Sb^3＋ ; As a result, the anticorrosion performance of carbon steel may be improved by PMA/SbBr3 inhibitor in 55% LiBr solution.

Effects of Mo Composites on the Corrosion Behaviors of Low Alloy Steel

By using electrochemical and weight loss methods, the effect of MoO42-on the corrosion behaviors of low alloy steel was investigated in the 55%LiBr＋0.07 mol/L LiOH solution at high temperature. The results show that MoO42 , being an anodic inhibitor, would form a passive film rapidly and impede both anodic and cathodic reactions. Moreover, Na2MoO4 effectively prevents corrosion in 55%LiBr＋0.07 mol/L LiOH solution when its concentration is higher than 200 mg/L. Some elements of alloy, such as chromium and nickel, may cause the widening of passive potential region and the decrease of passive density, which indicates that the corrosion resistance increases. AES analysis shows that molybdenum participates in forming a protection film. The synergistic effect between chromium and molybdenum induces Cr-steel to be in passive state in lower Na2MoO4 concentration.

Optimal Scheduling for Flexible Regional Integrated Energy Systemwith Soft Open Point

The Regional Integrated Energy System(RIES)has brought new modes of development,utilization,conversion,storage of energy.The introduction of Soft Open Point(SOP)and the application of Power to Gas(P2G)technology will greatly deepen the coupling of the electricity-gas integrated energy system,improve the flexibility and safety of the operation of the power system,and bring a deal of benefits to the power system.On this background,an optimal dispatch model of RIES combined cold,heat,gas and electricity with SOP is proposed.Firstly,RIES architecture with SOP and P2G is designed and its mathematical model also is built.Secondly,on the basis of considering the optimal scheduling of combined cold,heat,gas and electricity,the optimal scheduling model for RIES was established.After that,the original model is transformed into a mixed-integer second-order cone programming model by using linearization and second-order cone relaxation techniques,and the CPLEX solver is invoked to solve the optimization problem.Finally,the modified IEEE 33-bus systemis used to analyze the benefits of SOP,P2G technology and lithium bromide absorption chillers in reducing systemnetwork loss and cost,as well as improving the system’s ability to absorb wind and solar and operating safety.

Heat and mass transfer through spiral tubes in absorber of absorption heat pump system for waste heat recovery

Heat and mass transfer of a LiBr/water absorption heat pump system(AHP)was experimentally studied during working a heating-up mode.The examination was performed for a single spiral tube,which was simulated for heat transfer tubes in an absorber.The inside and outside of the tube were subjected to a film flow of the absorption liquid and exposed to the atmosphere,respectively.The maximum temperature of the absorption liquid was observed not at the entrance but in the region a little downward from the entrance in the tube.The steam absorption convective heat transfer coefficient between the liquid film flowing down and the inside wall of the temperature and the film temperature at the maximum temperature location and the bottom.The film heat and mass transfer coefficients rose with increasing Reynolds number of the liquid film stream.The coefficients showed opposite trend to the empirical correlation reported for laminar film flow on a straight smooth tube in a refrigeration mode in the past work.The fact can be caused due to a turbulent promotion effect of the liquid in a spiral tube.