Thermodynamics is the 19th century equivalent of the grand unified theory of the universe. Starting with Count Rumford and Sadi Carnot’s speculations about the heat produced by the boring of cannons, by the middle of the century a clutch of scientists had turned it into a robust conceptual framework that used energy and its distribution to join the dots between every chemical and physical phenomenon
For the operation of a nuclear power plant,optimizing chemical control and on-line monitoring of the coolant is a crucial specification.The water chemical control and on-line pH measurement for the next generation reactor,SCWR,were under extensively RD in the past decades.The progress in chemical control of the coolant and the techniques and instruments for on-line monitoring of pH of the coolant for SCWR was reviewed,and the implementation and development of both issues were prospected.
3,5,6-Trichloropyridin-2-ol sodium is an important intermediate of composite insecticide chlorpyrifos.With trichloroacetic chloride and acrylonitrile as raw material and o-dichlorobenzene as solvent,3,5,6-trichloropyridin-2-ol sodium was synthesized by cyclization and aromatization on the catalyst of cuprous chloride and copper.The selection of solvent,the way of charging acrylonitrile,the reflux method,the reuse of catalyst and the repeated use of raw materials were investigated.When o-dichlorobenzene was used as solvent,acrylonitrile was added all at once and the reflux liquid went back below the liquid level,the catalyst could be used repeatedly for ten times,and the raw materials were reusable after distillation,which made the operation more convenient for industrial production.The total yield reached 84.1%.
An efficient,mild and simple method for the oxidation of aromatic aldehyde to carboxylic acids using oxone/PTC under ultrasonic irradiation was described.The reaction was carried out with n(aromatic aldehyde)∶n(oxone)∶n(PTC)=1∶1∶0.2under ultrasonic irradiation for 2hat 50 ℃ and the yield exceeded 80%.
The synthesis of sodium formate by the reaction of carbon monoxide with sodium hydroxide in ethanol was studied.The effects of stirring speed,ethanol concentration,molar ratio of sodium hydroxide to carbon monoxide,partial pressure of carbon monoxide and reaction temperature on the reaction rate were investigated.The experimental results showed that the appropriate synthesis conditions of sodium formate were:the stirring speed of 300r/min,the ethanol concentration of 95%,the molar ratio of sodium hydroxide to carbon monoxide of 0.88,the partial pressure of carbon monoxide of 1.5MPa and the reaction temperature of 80℃.Under these conditions,the yield of sodium formate was 91.71%,and its purity was 100%.
The relationship between stability and rheological properties of pesticides with different formulations or bases was investigated by using the rotary rheometer.The yield stress,flow curve,stability degree,cohesive energy and viscosity of various samples were determined and compared with their stability.The results showed that the order of yield stresses determined under control-stress(CS)mode corresponded approximately to the stability of the samples while other rheological indexes were not.
A three-variable and three-level Box-Behnken experimental design was used to optimize the extraction process conditions of inorganic arsenic in the stem of wild ginseng based on the results of one-factor-at-a-time method.The effect of the three process conditions on the content of inorganic arsenic decreased in the following order:extraction time HCl concentration extraction temperature.The optimum extraction conditions were:the extraction concentration of 7.24 mol/L,extraction temperature at43.7℃ and extraction time of 36 min.The content of inorganic arsenic in theory and actual extraction process were 88.18ng/g respectively and 86.82ng/g with a relative error of 1.56%.
N-Carbobenzyloxy-L-alanine was synthesized using L-alanine(L-Ala)and N-(benzyloxycarbonyloxy)succinimide(Zosu)as raw material.The influential factors such as the kind of acid-binding agent,n(NaHCO3)∶n(Zosu)∶n(L-Ala),organic solvent,reaction time,reaction temperature and V(1,4-dioxane)/V(water),were investigated.The structure of the product was characterized by IR,1 H NMR and elemental analysis.The optimum conditions for synthesis of the title compound were determined as follows:n(NaHCO3)∶n(Zosu)∶n(L-Ala)=2∶1.2∶1,V1,4-dioxane∶Vwater=1.5∶1,and reacting for 3hat 25℃.The yield reached 97.7% under these optimum conditions.
Metamitron was synthesized from benzoyl nitrile as start material by hydrolysis and esterification with sulfuric acid,propionyl chloride and ethanol,Schiff's base reaction with acethydrazide,condensation with hydrazine in a mixture solvent of ethanol and toluene and cyclocondensation with sodium benzoate and aphase transfer catalyst with an overall yield of 72.2%(based on benzoyl nitrile).The operation was simplified,the purity of the target product was improved to 99.23%(by HPLC),and the cost was reduced.The improved synthetic process was easily to be scaled up.
The degradation of lignin catalyzed by functional basic ionic liquid was investigated.Higher conversion of lignin and simpler degradation product composition were obtained in the presence of basic ionic liquid,instead of traditional NaOH solution.The reaction conditions were optimized.Ultrasound-assisted test proved that the ultrasound pretreatment favored the degradation process.
