To provide theoretical and technical basis for the application of preparations of bamboo vinegar and copper sulfate in the prevention of green algae in floating system for tobacco seeding,the soaking and spraying meth...To provide theoretical and technical basis for the application of preparations of bamboo vinegar and copper sulfate in the prevention of green algae in floating system for tobacco seeding,the soaking and spraying methods were employed to study the effect of different concentrations of preparations of bamboo vinegar and copper sulfate on green algae and tobacco seedling growth. The results showed that the preparations of bamboo vinegar and copper sulfate of different concentrations played a strong role in inhibiting green algae growth and had better effect than copper sulfate. Spraying 1∶ 200 preparations of bamboo vinegar and copper sulfate could significantly promote tobacco seedling growth,and the leaf fresh weight increased by 15. 80% compared with CK,with significant difference; spraying 1∶ 50 preparations was not conducive to tobacco seedling growth. It was recommended to spray 1∶ 200 preparations of bamboo vinegar and copper sulfate in floating system for tobacco seeding,which could promote tobacco seedling growth and reduce green algae to varying degrees.展开更多
Leaching from silver sulfide.using a copper-thiosulfate solution in the absence of ammonia was investigated. It is found that silver sulfide could be effectively dissolved in the copper-thiosulfate system without ammo...Leaching from silver sulfide.using a copper-thiosulfate solution in the absence of ammonia was investigated. It is found that silver sulfide could be effectively dissolved in the copper-thiosulfate system without ammonia. The effects of thiosulfate concentration, cop- per-to-thiosulfate ratio, agitation vigorousness, pH values, and dissolved gases on the leaching of silver sulfide with the copper-thiosulfate solution were studied. A maximum extraction of 95.1% was achieved with the 0.12 mol/L thiosulfate and the 0.048 rnol/L copper sulfate. It is shown that copper-to-thiosulfate ratio is an important factor in silver sulfide dissolution and oxygen is not needed to leach silver sulfide, which leads to the instability of the leaching system at high copper-to-thiosulfate ratio. On the other hand, the silver extraction is not affected by the pulp pH values.展开更多
The oxidation of lignite and bituminous coal samples modified by 5 wt%(in terms of dry salt)addition of copper salts Cu(NO_(3))_(2),CuSO_(4),and Cu(CH_(3)COO)_(2) was studied.The samples’reactivity was studied by the...The oxidation of lignite and bituminous coal samples modified by 5 wt%(in terms of dry salt)addition of copper salts Cu(NO_(3))_(2),CuSO_(4),and Cu(CH_(3)COO)_(2) was studied.The samples’reactivity was studied by thermogravimetry within a temperature range of 45–600℃ at a heating rate of 2.5℃/min in an oxidizing environment.The introduction of activating additives has resulted in a significant decrease in the temperature of intense oxidation onset(ΔT_(i)=20/94℃),in a reduction in the sample residence time in the volatile matter release region(Δt_(e)=2/22 min)and the total duration of the coal combustible mass oxidation(Δt_(f)=8/14 min).The Friedman method was used to calculate the activation energy values for the oxidation process of the modified samples.The maximum change in activation energy values was observed for the bituminous coal sample.The possible mechanism behind the action of the copper-salt additives,which activate the oxidation of lignite and bituminous coal,is discussed.According to the data of mass spectrometric analysis,the concentration of NOx in the reaction products decreases as the temperature of the activated oxidation process is shifted towards the low-temperature region.展开更多
文摘To provide theoretical and technical basis for the application of preparations of bamboo vinegar and copper sulfate in the prevention of green algae in floating system for tobacco seeding,the soaking and spraying methods were employed to study the effect of different concentrations of preparations of bamboo vinegar and copper sulfate on green algae and tobacco seedling growth. The results showed that the preparations of bamboo vinegar and copper sulfate of different concentrations played a strong role in inhibiting green algae growth and had better effect than copper sulfate. Spraying 1∶ 200 preparations of bamboo vinegar and copper sulfate could significantly promote tobacco seedling growth,and the leaf fresh weight increased by 15. 80% compared with CK,with significant difference; spraying 1∶ 50 preparations was not conducive to tobacco seedling growth. It was recommended to spray 1∶ 200 preparations of bamboo vinegar and copper sulfate in floating system for tobacco seeding,which could promote tobacco seedling growth and reduce green algae to varying degrees.
基金supported by the Joint Foundation of the National Natural Science Foundation Committee and Yunnan Provincial Government of China (No. U0937602)
文摘Leaching from silver sulfide.using a copper-thiosulfate solution in the absence of ammonia was investigated. It is found that silver sulfide could be effectively dissolved in the copper-thiosulfate system without ammonia. The effects of thiosulfate concentration, cop- per-to-thiosulfate ratio, agitation vigorousness, pH values, and dissolved gases on the leaching of silver sulfide with the copper-thiosulfate solution were studied. A maximum extraction of 95.1% was achieved with the 0.12 mol/L thiosulfate and the 0.048 rnol/L copper sulfate. It is shown that copper-to-thiosulfate ratio is an important factor in silver sulfide dissolution and oxygen is not needed to leach silver sulfide, which leads to the instability of the leaching system at high copper-to-thiosulfate ratio. On the other hand, the silver extraction is not affected by the pulp pH values.
基金This work was supported by the Ministry of Science and Higher Education of the Russian Federation(projects No.FSWW-2020-0022 and AAAA-A17-117041710086-6).
文摘The oxidation of lignite and bituminous coal samples modified by 5 wt%(in terms of dry salt)addition of copper salts Cu(NO_(3))_(2),CuSO_(4),and Cu(CH_(3)COO)_(2) was studied.The samples’reactivity was studied by thermogravimetry within a temperature range of 45–600℃ at a heating rate of 2.5℃/min in an oxidizing environment.The introduction of activating additives has resulted in a significant decrease in the temperature of intense oxidation onset(ΔT_(i)=20/94℃),in a reduction in the sample residence time in the volatile matter release region(Δt_(e)=2/22 min)and the total duration of the coal combustible mass oxidation(Δt_(f)=8/14 min).The Friedman method was used to calculate the activation energy values for the oxidation process of the modified samples.The maximum change in activation energy values was observed for the bituminous coal sample.The possible mechanism behind the action of the copper-salt additives,which activate the oxidation of lignite and bituminous coal,is discussed.According to the data of mass spectrometric analysis,the concentration of NOx in the reaction products decreases as the temperature of the activated oxidation process is shifted towards the low-temperature region.