摘要:
Biotransformation products of a fermentation with Streptomyces sp., (Merck Culture Collection MA7165) ATCC No. 55946 are potent antifungal agents. These products may be useful in the treatment of diseases caused by fungal pathogens such as Candida sp. and Cryptococcus neoformans.
摘要:
An acyclic tricarboxylic compound has been isolated from a culture of MF5453. The compound and its derivatives are active as squalene synthetase inhibitors and are useful in the treatment of hypercholesterolemia.
摘要:
A compound having the formula ##STR1## which is useful as an antifungal agent and for the treatment and control of several agricultural phytopathogens, including Phytophthora infestans, is disclosed.
摘要:
This invention relates to a method of recovering non-ferrous metal sulfides from a metal ore which comprises subjecting the metal ore, in the form of an aqueous pulp, to a froth flotation process in the presence of a flotating amount of a flotation collector wherein the collector comprises a compound which corresponds to one of the formulas ##STR1## wherein R.sup.1 is alkyl, aryl or aralkyl group wherein the aryl and aralkyl can be substituted with a halo or alkyl moiety;R.sup.2 is alkyl, aryl or aralkyl group wherein the aryl or aralkyl can be substituted with a halo or alkyl moiety;R.sup.3 is aryl or aralkyl unsubstituted or substituted with a halo or alkyl moiety;R.sup.4 is alkyl, aryl or aralkyl group wherein the aryl or aralkyl can be substituted with a halo or alkyl moiety; with the proviso that at least one of R.sup.1 and R.sup.2 must be aryl or aralkyl unsubstituted or substituted;under conditions such that the metal sulfide values are recovered in the froth.The collectors of this process are useful under alkaline, neutral and acidic conditions. Such collectors give good recoveries of the mineral sulfide values, with a high selectivity toward the non-ferrous metal sulfide values over the ferrous containing minerals.The novel collectors of this invention result in surprisingly high recovery of nonferrous metal values or sulfidized metal oxide values, and a surprisingly high selectivity toward such nonferrous metal values when such metal values are found in the presence of ferrous-containing metal sulfides. These collectors demonstrate good recovery and good kinetics.
摘要:
The present invention relates to a process for separating pyrite from sulfide ores and coal during flotation separation which comprises the depressing of pyrite with from about 0.05 to 0.75 kilograms per ton of concentrate solids using a pyrite depressant compounds selected from the group consisting of R1, R2, R3 N.sup.+ O.sub.2 H.sub.4 SR4X.sup.- (I) where R1, R2 and R3 are lower alkyls wherein the final sum of the carbon atoms is in a range of 3 to 6, R4 is selected from a group consisting of hydrogen (H) and amidine and X is chlorine, bromine or iodine, ##STR1## where Ro is a lower alkyl having carbon atoms in a range of 3 to 8 with 3 to 6 being preferred and a final pH in a range of 4 to 9 depending on the ore being processed, and therafter recovering the flotation concentrate thus obtained. As to group (I) compounds, 2-trimethylammonium-ethane isothiuronium dichloride (TMAE) as a pyrite depressant is surprisingly effective in pyrite removal being substantially independent of the pH values of the treated ore or coal, compatible with conventional collector reagents such as xanthates in the case of copper sulfide bearing ores as well as being substantially unobtrusive in not depressing other useful ore sulfides, including but limited to chalcopyrite, bornite chalcosite. Group (II) are more pH sensitive.
摘要:
11-hydroxysordarin, biotransformation product of a fermentation with sordarin and Actinomyces spp., (Merck Culture Collection MA7235) ATCC No. 202103 is an antifungal agent. This compound may be useful in the treatment of diseases caused by fungal pathogens such as Candida albicans.
摘要:
A process for the recovery of mineral values by froth flotation in an aqueous medium from mineral ores with the use of an effective amount of a sulfide-containing polyalkylene oxide frother.