The effect of the reduction conditions of iron-copper catalysts on their physicochemical characteristics

1965 ◽  
Vol 1 (3) ◽  
pp. 189-191
Author(s):  
L. Kh. Kazan ◽  
A. L. Klyachko-Gurvich ◽  
I. B. Rapoport ◽  
A. M. Rubinshtein
Keyword(s):  
Copper Catalysts ◽  
Physicochemical Characteristics ◽  
Iron Copper

The composition of esters obtained by synthesis from CO and H over iron-copper catalysts

1962 ◽  
Vol 1 (4) ◽  
pp. 555-563
Author(s):  
M ULANOVA ◽  
I RAPOPORT ◽  
A POLYAKOVA ◽  
T ITSIKSON
Keyword(s):  
Copper Catalysts ◽  
Iron Copper

Hydrogenation of some oxygen-containing compounds on deposited iron-copper catalysts

1963 ◽  
Vol 2 (1) ◽  
pp. 76-82
Author(s):  
B VAINSHTEIN ◽  
L KAGAN ◽  
I RAPOPORT ◽  
V KRUGLIKOV ◽  
V KAPKIN
Keyword(s):  
Copper Catalysts ◽  
Iron Copper

Decomposition of CO−H2over Graphite Nanofiber-Supported Iron and Iron−Copper Catalysts

2004 ◽  
Vol 108 (35) ◽  
pp. 13307-13314 ◽  
Author(s):  
O. C. Carneiro ◽  
P. E. Anderson ◽  
N. M. Rodriguez ◽  
R. T. K. Baker
Keyword(s):  
Copper Catalysts ◽  
Iron Copper ◽  
Supported Iron

scholarly journals Chemical Evaluation of Trace Elements in Bottled Water

2020 ◽  
Vol 2020 ◽  
pp. 1-16
Author(s):  
Bikram Gautam
Keyword(s):  
Trace Elements ◽  
Physicochemical Characteristics ◽  
Bottled Water ◽  
Total Hardness ◽  
Residual Chlorine ◽  
Cobalt Nickel ◽  
Iron Copper ◽  
Cadmium And Lead ◽  
Nickel Fluoride ◽  
Sodium And Potassium

Sales of bottled water have been increasing around the globe. This study was carried out to assess the trace elements present in bottled water. For the study of bottled water, a total of 100 samples of different volumes (20 L and 1 L) were selected. The physicochemical assessments were performed as per the methods described in the American Public Health Association, 2005. Average values of pH, electrical conductivity, total dissolved solids, and turbidity were found to be 5.96 ± 0.54, 59.97 ± 58.65, 4.42 ± 3.69, and 0.408 ± 0.19, respectively. Likewise, average values of total hardness (as CaCO3), calcium (as CaCO3), magnesium (as CaCO3), chlorine, iron, copper, cobalt, nickel, fluoride, sodium, and potassium were found to be 14.78 ± 8.43, 3.26 ± 1.55, 11.51 ± 7.92, 7.51 ± 3.21, 0.0032 ± 0.0017, 0.0091 ± 0.0116, 0.2520 ± 0.0127, 0.0080 ± 0.0082, 0.047 ± 0.0139, 12.65 ± 10.90, and 1.41 ± 2.00, respectively; meanwhile residual chlorine, zinc, silver, cadmium, and lead were below detection limit. All the physicochemical characteristics of bottled water were found to be within International Bottled Water Association (IBWA) guidelines. From the physicochemical aspects, the bottled water was found to be within the permissible value set by IBWA. Pearson’s correlation revealed significant association between trace elements. Levene’s test for equity of variances indicated that the majority (iron, copper, cobalt, nickel, fluoride, sodium, and potassium) of trace elements and seasons (monsoon and postmonsoon) demonstrated a statistically significant distribution (at 95% confidence interval). At elevated concentrations, some elements can be harmful to human health and can cause morphological abnormalities, mutagenic effects, reduced growth, and increased morbidity and mortality in humans but it all depends upon a person’s metabolic factors, genetic factors, and ability to excrete trace elements through different routes, etc. Water could have percolated down from the surface to the ground water and as such the difference in concentration of trace elements in monsoon and postmonsoon seasons could be noticeable.

Purity-enhanced bulk synthesis of thin single-wall carbon nanotubes using iron–copper catalysts

2011 ◽  
Vol 22 (39) ◽  
pp. 395602 ◽  
Author(s):  
H E Lim ◽  
Y Miyata ◽  
T Nakayama ◽  
S Chen ◽  
R Kitaura ◽  
...  
Keyword(s):  
Carbon Nanotubes ◽  
Copper Catalysts ◽  
Single Wall Carbon Nanotubes ◽  
Single Wall Carbon ◽  
Iron Copper

Fine Structure of Type IV Glycogenosis

1981 ◽  
Vol 39 ◽  
pp. 464-465
Author(s):  
P.K. Simons
Keyword(s):  
Needle Biopsy ◽  
Tissue Concentration ◽  
Inborn Errors ◽  
Rare Type ◽  
Type Iv ◽  
Iron Copper ◽  
Proper Diagnosis ◽  
Type Iv Glycogenosis ◽  
Loss Of Appetite ◽  
Enzymatic Defect

Glycogenosis is defined as any condition in which the tissue concentration of glycogen is increased. There are currently ten recognized variants of glycogenosis that are heritable inborn errors of metabolism. The specific enzymatic defect in each of the variants is known or at least suspected. In all cases, the enzymatic defect prevents the proper metabolism or formation of the glycogen molecule. The clinical and histologic differences between the types of glycogenosis is important to a proper diagnosis after the presence of such a condition is realized. This study was initiated to examine the ultrastructure of the rare Type IV Glycogenosis (Amylopectinosis) of which there is very little morphologic characterization in the literature.Liver tissue was obtained by needle biopsy from a 12-month-old Oriental female who was originally admitted to the hospital after observation of poor development, loss of appetite, and hepatomegaly. The majority of the tissue was fixed for light microscopy in neutral buffered formalin and processed using routine and special staining procedures (reticulin, trichrome, iron, copper, PAS, PAS-diastase and PAS-pectinase.

Applications of SEM/EDXA in cement clinker investigation

1990 ◽  
Vol 48 (4) ◽  
pp. 870-871
Author(s):  
Arezki Tagnit-Hamou ◽  
Shondeep L. Sarkar
Keyword(s):  
Mineralogical Composition ◽  
Physicochemical Characteristics ◽  
Cement Clinker ◽  
Accurate Information ◽  
Phase Identification ◽  
History Of ◽  
Bulk Chemical ◽  
Resolution Imaging ◽  
Proven Method ◽  
Instantaneous Chemical

All the desired properties of cement primarily depend on the physicochemical characteristics of clinker from which the cement is produced. The mineralogical composition of the clinker forms the most important parameter influencing these properties.Optical microscopy provides reasonably accurate information pertaining to the thermal history of the clinker, while XRDA still remains the proven method of phase identification, and bulk chemical composition of the clinker can be readily obtained from XRFA. Nevertheless, all these microanalytical techniques are somewhat limited in their applications, and SEM/EDXA combination fills this gap uniquely by virtue of its high resolution imaging capability and possibility of instantaneous chemical analysis of individual phases.Inhomogeneities and impurities in the raw meal, influence of kiln conditions such as sintering and cooling rate being directly related to the microstructure can be effectively determined by SEM/EDXA. In addition, several physical characteristics of cement, such as rhcology, grindability and hydraulicity also depend on the clinker microstructure.

Common modifications of selenocysteine in selenoproteins

2019 ◽  
Vol 64 (1) ◽  
pp. 45-53 ◽  
Author(s):  
Elias S.J. Arnér
Keyword(s):  
Amino Acids ◽  
Covalent Binding ◽  
Physicochemical Characteristics ◽  
Redox Active

Abstract Selenocysteine (Sec), the sulfur-to-selenium substituted variant of cysteine (Cys), is the defining entity of selenoproteins. These are naturally expressed in many diverse organisms and constitute a unique class of proteins. As a result of the physicochemical characteristics of selenium when compared with sulfur, Sec is typically more reactive than Cys while participating in similar reactions, and there are also some qualitative differences in the reactivities between the two amino acids. This minireview discusses the types of modifications of Sec in selenoproteins that have thus far been experimentally validated. These modifications include direct covalent binding through the Se atom of Sec to other chalcogen atoms (S, O and Se) as present in redox active molecular motifs, derivatization of Sec via the direct covalent binding to non-chalcogen elements (Ni, Mb, N, Au and C), and the loss of Se from Sec resulting in formation of dehydroalanine. To understand the nature of these Sec modifications is crucial for an understanding of selenoprotein reactivities in biological, physiological and pathophysiological contexts.

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