scholarly journals INTERMEDIATE COMPOUND FORMATION WITH PEROXIDASE AND STRONG OXIDIZING AGENTS

1953 ◽  
Vol 201 (1) ◽  
pp. 413-426 ◽  
Author(s):  
Philip George
Keyword(s):  
Intermediate Compound ◽  
Compound Formation ◽  
Oxidizing Agents

Platinum-group minerals in the Selukwe Subchamber, Great Dyke, Zimbabwe: implications for PGE collection mechanisms and post-formational redistribution

1993 ◽  
Vol 57 (389) ◽  
pp. 613-633 ◽  
Author(s):  
Bronwen M. Coghill ◽  
Allan H. Wilson
Keyword(s):  
Base Metal ◽  
Process Model ◽  
Intermediate Compound ◽  
Compound Formation ◽  
Great Dyke ◽  
Platinum Group Minerals ◽  
Single Process ◽  
Base Metal Sulphides ◽  
Platinum Group ◽  
Pge Mineralisation

AbstractThis paper presents the results of microprobe investigations of the Platinum-Group Elements (PGE) of the Selukwe Subchamber, Great Dyke, Zimbabwe. The PGE are associated with base metal sulphides in the uppermost pyroxenites of the Ultramafic Sequence of the Great Dyke. The following minerals have been indentified: bismuthotellurides (moncheite, maslovite, michenerite, kotulskite and polarite); arsenides (sperrylite); and sulphides and sulpharsenides (cooperite, laurite, braggite and hollingworthite). Platinum Group Minerals (PGM) occur in three distinct textural environments: (1) at the boundary of sulphides and silicates/hydrosilicates, (2) entirely enclosed within sulphides, and (3) entirely enclosed within silicate or hydrosilicate minerals. The stratigraphic distribution, environments and textures of the PGM have important genetic implications, and cannot be explained by a single process. A multi-process model for the petrogenesis of the PGE mineralisation in terms of complexation and intermediate compound formation is proposed. The primary mineralising events were due to orthomagmatic processes, but the observed textures are the result of microscale remobilisation of PGM components by trapped interstitial fluids (bydromagmatic processes).

scholarly journals The Physiology of Sugar-Cane V. Kinetics of Sugar Accumulation

1962 ◽  
Vol 15 (3) ◽  
pp. 429 ◽  
Author(s):  
RL Bieleski
Keyword(s):  
Sugar Cane ◽  
Accumulation Rate ◽  
Intermediate Compound ◽  
Sugar Concentration ◽  
Hyperbolic Function ◽  
Sugar Accumulation ◽  
Compound Formation ◽  
Kinetics Of

Radioisotope techniques were used to study kinetics of sucrose, glucose, and fructose accumulation in slices of immature sugar�cane tissue. For all three sugars, accumulation rate was P. hyperbolic function of sugar concentration, suggesting intermediate compound formation between the sugars and some receptor or "carrier" in the cell. Sucrose and glucose interacted competitively, implying that, these two sugars (and probably also fructose, fructose 6-phosphate, and glucose I-phosphate) shared the same carrier.

An Electron Microscope Study of Interdiffusion and Compound Formation in Ta-Au Thin Films

1973 ◽  
Vol 31 ◽  
pp. 32-33 ◽  
Author(s):  
T. C. Tisone ◽  
S. Lau
Keyword(s):  
Electron Microscope ◽  
Electron Microscope Study ◽  
Thermally Grown Oxide ◽  
Ion Milling ◽  
Compound Formation ◽  
Technology Application ◽  
Transmission Electron ◽  
Before And After ◽  
Au Thin Films

In a study of the properties of a Ta-Au metallization system for thin film technology application, the interdiffusion between Ta(bcc)-Au, βTa-Au and Ta2M-Au films was studied. Considered here is a discussion of the use of the transmission electron microscope(TEM) in the identification of phases formed and characterization of the film microstructures before and after annealing.The films were deposited by sputtering onto silicon wafers with 5000 Å of thermally grown oxide. The film thicknesses were 2000 Å of Ta and 2000 Å of Au. Samples for TEM observation were prepared by ultrasonically cutting 3mm disks from the wafers. The disks were first chemically etched from the silicon side using a HNO3 :HF(19:5) solution followed by ion milling to perforation of the Au side.

Modern Greek V V dvandva compounds: A linguistic innovation in the history of the Indo-European languages

2009 ◽  
Vol 2 (1) ◽  
pp. 48-68 ◽  
Author(s):  
Angela Ralli
Keyword(s):  
Language Contact ◽  
High Rate ◽  
Compound Formation ◽  
Modern Greek ◽  
Late Medieval Period ◽  
European Languages ◽  
History Of ◽  
Internal Change ◽  
Contact Situation ◽  
Asian Languages

This paper deals with [V V] dvandva compounds, which are frequently used in East and Southeast Asian languages but also in Greek and its dialects: Greek is in this respect uncommon among Indo-European languages. It examines the appearance of this type of compounding in Greek by tracing its development in the late Medieval period, and detects a high rate of productivity in most Modern Greek dialects. It argues that the emergence of the [V V] dvandva pattern is not due to areal pressure or to a language-contact situation, but it is induced by a language internal change. It associates this change with the rise of productivity of compounding in general, and the expansion of verbal compounds in particular. It also suggests that the change contributes to making the compound-formation patterns of the language more uniform and systematic. Claims and proposals are illustrated with data from Standard Modern Greek and its dialects. It is shown that dialectal evidence is crucial for the study of the rise and productivity of [V V] dvandva compounds, since changes are not usually portrayed in the standard language.

Interionic Pair Potential, hard sphere diameter and entropy of mixing of NaCd compound forming binary molten alloys under the framework of Pseudopotential theory

2014 ◽  
Vol 10 (6) ◽  
pp. 2843-2852
Author(s):  
Sujeet Kumar Chatterjee ◽  
Lokesh Chandra Prasad ◽  
Ajaya Bhattarai
Keyword(s):  
Nearest Neighbor ◽  
Effective Interaction ◽  
Pair Potential ◽  
Sphere Diameter ◽  
Compound Formation ◽  
Pseudopotential Theory ◽  
Energy Of Mixing ◽  
Asymmetric Behaviour ◽  
Statistical Mechanical ◽  
Free Energy Of Mixing

The observed asymmetric behaviour of mixing of  NaCd liquid alloys around equiatomic composition with smaller negative values for free energy of mixing at compound forming concentration, i.e. GMXS = -4.9KJ at Ccd =0.66 has  aroused our interest to undertake a theoretical investigation of this system.A simple statistical mechanical theory based on compound formation model has been used to investigate the energetics of formation of intermetallic compound Cd2Na in the melt through the study of entropy of mixing.Besides, the interionic interactions between component atoms Na and Cd of the alloys have been understood through the study of interionic pair potential фij(r), calculated from pseudopotential theory in the light of CF model.Our study of фij(r) suggest that the effective interaction between Na-Na atoms decreases on alloying with Cd atom, being minimum for compound forming alloy( Cd 0.66 Na 0.34 ).The nearest neighbor distance between Na-Na atoms does not alter on alloying. Like wise Na-Na,  effective interaction between  Cd-Cd atom decreases from pure state to NaCd alloys, being smaller at compound forming  concentration Cd 0.66 Na 0.34.The computed values of SM from pseudopotential theory are positive at all concentrations, but the agreement between theory and experimental is not satisfactory. This might be happening due to parameterisation of σ3 and Ψcompound.

Natural Products and Extracts as Xantine Oxidase Inhibitors – A Hope for Gout Disease?

2020 ◽  
Vol 26 ◽  
Author(s):  
Ilkay Erdogan Orhan ◽  
Fatma Sezer Senol Deniz
Keyword(s):  
Natural Products ◽  
Uric Acid ◽  
Waste Product ◽  
Acid Synthesis ◽  
Intermediate Compound ◽  
Living System ◽  
Ginsenoside Rd ◽  
Drug Classes ◽  
Urate Crystal ◽  
High Concentrations

: Xanthine oxidase (EC 1.17.3.2) (XO) is one of the main enzymatic sources that create reactive oxygen species (ROS) in the living system. It is a dehydrogenase enzyme that performs electron transfer to nicotinamide adenine dinucleotide (NAD+ ), while oxidizing hypoxanthin, which is an intermediate compound in purine catabolism, first to xanthine and then to uric acid. XO turns into an oxidant enzyme that oxidizes thiol groups under certain stress conditions in the tissue. The last metabolic step, in which hypoxanthin turns into uric acid, is catalyzed by XO. Uric acid, considered a waste product, can cause kidney stones and gouty-type arthritis as it is crystallized, when present in high concentrations. Thus, XO inhibitors are one of the drug classes used against gout, a purine metabolism disease that causes urate crystal storage in the joint and its surroundings caused by hyperuricemia. Urate-lowering therapy include XO inhibitors that reduce uric acid production as well as uricosuric drugs that increase urea excretion. Current drugs that obstruct uric acid synthesis through XO inhibition are allopurinol, febuxostat, and uricase. However, since the side effects, safety and tolerability problems of some current gout medications still exist; intensive research is ongoing to look for new, effective, and safer XO inhibitors of natural or synthetic origins for the treatment of the disease. In the present review, we aimed to assess in detail XO inhibitory capacities of pure natural compounds along with the extracts from plants and other natural sources via screening Pubmed, Web of Science (WoS), Scopus, and Google Academic. The data pointed out to the fact that natural products, particularly phenolics such as flavonoids (quercetin, apigenin, and scutellarein), tannins (agrimoniin and ellagitannin), chalcones (melanoxethin), triterpenes (ginsenoside Rd and ursolic acid), stilbenes (resveratrol and piceatannol), alkaloids (berberin and palmatin) have a great potential for new XO inhibitors capable of use against gout disease. In addition, not only plants but other biological sources such as microfungi, macrofungi, lichens, insects (silk worms, ants, etc) seem to be the promising sources of novel XO inhibitors.

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