Leaching of gold ores with high cyanicides: a physico-chemical modeling approach

Mineralogy and uranium leaching of ores from Triassic Peribaltic sandstones

The recovery of uranium and other valuable metals from Polish Peribaltic sandstones were examined. The solid-liquid extraction is the first stage of the technology of uranium production and it is crucial for the next stages of processing. In the laboratory experiments uranium was leached with efficiencies 71-100 % by acidic lixiviants. Satisfactory results were obtained for the alkaline leachin...

Bacterial leaching of discarded copper ores from Yongping, China

The elementary and phase analysis of discarded copper ores from Yongping of China has been performed. The experiments of extracting copper from the discarded copper ores were done with the mixed bacteria obtained through a series of enrichment, separation, domestication and combination tests. The results show that in the process of bioleaching, the pH value rises at first and drops gradually. T...

Modeling Gold Volatility: Realized GARCH Approach

F orecasting the volatility of a financial asset has wide implications in finance. Conditional variance extracted from the GARCH framework could be a suitable proxy of financial asset volatility. Option pricing, portfolio optimization, and risk management are examples of implications of conditional variance forecasting. One of the most recent methods of volatility forecasting is Real...

First Principles Multiscale Modeling of Physico-Chemical Aspects of Tribology

We have been developing methods to obtain a fundamental understanding of the physico-chemistry of sliding systems in contact that underlies the materials science and mechanics issues essential to tribology. Advances in theory and methods are now making it practical to consider fully first principles (de novo) predictions of surface and interface structures and their role in determining tribolog...

A Combined Chemical and Biological Heap Leaching of an Oxide Gold-bearing Ore

extraction and acetylation of purified trypsin from bovin pancreas and study of some its physico-chemical properties

آنزیم تریپسین در شرایط قلیایی ناپایدار می باشد .و فعالیت پروتئولیتیکی تریپسین منجربه خود هضمی آن در جایگاههای خاصی می گردد. بنابر این آنزیمی با ناپایداری بالا محسوب میگردد. در سالهای اخیر موفق شدند که با ایجاد تغیرات شیمیایی با اضافه کردن فلزات خاص ، کلسیم و یا عمل استیلاسیون منجر به افزایش پایداری آنزیم تریپسین گردند. مطالعات در حال حاضر نشان می دهد که تریپسین استیله شده فعالیت آنزیمی خود را ...