(n.) Native carbon in hexagonal crystals, also foliated or granular massive, of black color and metallic luster, and so soft as to leave a trace on paper. It is used for pencils (improperly called lead pencils), for crucibles, and as a lubricator, etc. Often called plumbago or black lead.
Example Sentences:
(1) Here we present images of polydeoxyadenylate molecules aligned in parallel, with their bases lying flat on a surface of highly oriented pyrolytic graphite and with their charged phosphodiester backbones protruding upwards.
(2) This is a report on a male patient of 71 years of age who had been a graphite mill worker for about 14 years.
(3) The concentration of gold in whole blood was determined using graphite furnace atomic absorption spectrophotometry.
(4) As subcritical crack velocities under cyclic loading were found to be many orders of magnitude faster than those measured under equivalent monotonic loads and to occur at typically 45% lower stress-intensity levels, cyclic fatigue in pyrolytic carbon-coated graphite is reasoned to be a vital consideration in the design and life-prediction procedures of prosthetic devices manufactured from this material.
(5) A 5-year-old boy had an excisional biopsy of a pigmented scleral lesion thought clinically to be a foreign body, probably graphite from a pencil.
(6) A membrane-free glucose sensor was made by covalent immobilization of glucose oxidase on graphite followed by adsorption of N-methyl-phenazinium ion (PMS+).
(7) Stearate-modified graphite paste recording electrodes were acutely or chronically implanted into the nucleus accumbens along with bipolar stimulating electrodes in the ipsilateral ventral tegmental area (VTA).
(8) I describe a micro-scale method for determining lead in whole blood by utilizing a graphite furnace.
(9) The reconstituted acid mixture is injected into the graphite tube atomizer for analysis of Cu and Cd and aspirated into the air--acetylene flame for measurement of Zn.
(10) A spokesman said Graphite had “received no income or interest payments, or proceeds of any kind, from its investment in City & County”.
(11) Tissue reactivity to carbon cloth, graphite cloth and vitreous carbon in the solid was studied in dogs.
(12) The mercury-graphite electrode was also checked in respect of both the plating time and the amount of analyses performed.
(13) Tritium retention noted in graphite tiles underscores the significance of material selection in present and future 3H-fueled fusion devices.
(14) The resolution of the enantiomers of three closely related benzodiazepines, temazepam, oxazepam and lorazepam, is attempted on three new column systems: cellulose triacetate, beta-cyclodextrin and the reversed-phase column porous graphitic carbon with beta-cyclodextrin as a mobile phase additive.
(15) For some metals the analysis can be directly achieved by means of atomisation of the biological liquid in a flame or in a graphite furnace; for other metals it is necessary a treatment of the sample to separate the metal from the rest of the matrix, which can be: calcination, microcalcination, mining.
(16) A new grade of graphite-isotropic, fine-grained, and of superior strength-has been produced at the Oak Ridge National Laboratory.
(17) We believe that the introduction of high-performance background correction such as Smith-Hieftje, delayed atomization techniques, and aerosol deposition have taken graphite furnace AAS into its third phase.
(18) Zinc was analyzed by flame atomic absorption spectrophotometry, and the other elements by graphite furnace atomic absorption.
(19) An analysis of the product of interaction of a sample of native DNA with a large pyrolytic graphite electrode in the presence of formaldehyde at approximately neutral pH did not prove changes in the secondary structure of native DNA due to its interaction with the graphite electrode.
(20) Alternatively, a 50-mu-l sample of blood or erythrocytes is treated with 50 mu-l of concentrated nitric acid and a 1.5-mu-l aliquot is analyzed with use of the graphite tube.
Hexagonal
Definition:
(a.) Having six sides and six angles; six-sided.
Example Sentences:
(1) The crystallographic parameters of four different unit cells, all of which are based on hexagonal packing arrangements, indicate that the fundamental unit of the complex is composed of six gene 5 protein dimers.
(2) The molecular structure of the hexagonal crystal form of porcine pepsin (EC 3.4.23.1), an aspartic proteinase from the gastric mucosa, has been determined by molecular replacement using the fungal enzyme, penicillopepsin (EC 3.4.23.6), as the search model.
(3) The "hexagonal ribbon" model proposes that hexagonal profiles are true cross-sections of elongated hexagonal ribbons.
(4) Crystal structure analysis and refinement at 2.0 A resolution of a rhombohedral crystal form of human annexin V at high calcium concentration revealed a domain motion compared to the previously analysed hexagonal crystal form.
(5) Abnormalities included absence of a hexagonal pattern, incomplete portal tracts with dilated veins only, lack of bile ducts and canaliculi, and apparent failure of bile formation and glycogen deposition.
(6) Using a hexagonal electrode array and switching times of 75 min at 45 V for 14 days, nine bands could be resolved.
(7) The PENN-PET scanner consists of six hexagonally arranged position-sensitive Nal(TI) detectors.
(8) This result was quite the same as that of the hexagonal plate crystals.
(9) When negatively stained with uranyl acetate, LPSI was ribbon-like but LPSII exhibited hexagonal lattice structures.
(10) Endothelial specular photography during an attack reveals dramatic changes: large black nonreflecting areas between quite normal-looking hexagonal cells.
(11) It is suggested that distortion in the hexagonal lattice below the pretransition temperature previously reported by X-ray diffraction techniques may be responsible for interchain interactions which give rise to a Raman band observed only in the triclinic lattice of even-numbered n-alkanes.
(12) 31P-NMR and X-ray diffraction techniques are used to study the comparative ability of myelin basic protein (MBP) vs. other basic proteins to convert hexagonal (HII) phases to stable lamellar (L alpha) structures.
(13) The influence of the intercalation of ethidium bromide (EB) on the characteristics of the DNA cholesteric and hexagonal mesophases is studied by optical microscopy, circular dichroism, and X-ray diffraction.
(14) Wide angle X-ray diffraction results indicate no major effect of the protein on the 4.1 A spacing, characteristic of hexagonal packing of the hydrocarbon chains.
(15) After in vitro perfusion of cytochalasin D to the corneal endothelium, the F-actin became randomly distributed throughout the cytoplasm, the hexagonal shape of the endothelial cell was disrupted, and endothelial permeability to carboxyfluorescein increased.
(16) The thermophilic eubacterium Clostridium thermohydrosulfuricum L77-66 is covered by a crystalline surface layer composed of identical glycoprotein subunits which are arranged in a hexagonal lattice with centre-to-centre spacings of approx.
(17) Pyramidal, cubical or hexagonal magnetic grains could be seen in different species of bacteria.
(18) The six subunits form a hexagon which is skewed with respect to the main rows of hexagons in such a way that the subunits lie on rows which make an angle of approximately 37 degrees with the main rows.
(19) In the invaginating synapses of cone pedicles, the plasma membrane of the photoreceptor ending contains an aggregate of A-face particles, a hexagonal array of synaptic vesicle sites, and rows of coated vesicle sites, which are deployed in sequence from apex to base of the synaptic ridge.
(20) The design and construction of a transistor-driven hexagonal contour-clamped homogeneous electric field (CHEF) apparatus is discussed in detail.