(n.) A white or gray crystalline salt, with a slight alkaline taste, used as a flux, in soldering metals, making enamels, fixing colors on porcelain, and as a soap. It occurs native in certain mineral springs, and is made from the boric acid of hot springs in Tuscany. It was originally obtained from a lake in Thibet, and was sent to Europe under the name of tincal. Borax is a pyroborate or tetraborate of sodium, Na2B4O7.10H2O.
Example Sentences:
(1) The relation of respiratory symptoms, pulmonary function, and abnormalities of chest radiographs to estimated exposures of borax dust has been investigated in a cross sectional study of 629 actively employed borax workers.
(2) In the borax zone the pH is increased compared with the pH of the mobile phase, and when omeprazole (a weak acid) is co-eluting in the borax zone its retention is affected.
(3) We found that in certain buffers, such as tris(hydroxymethyl)-aminomethane-hydrochloride, boric acid-borax, and N-hydroxyethyl piperazine-N'-2-ethanesulfonic acid-sodium hydroxide, hemoglobins released from erythrocytes were easily precipitated by addition of Zn2+, thus resulting in a false inhibition of hemolysin by Zn2+ when hemolysis was assayed by measuring absorbance at 540 nm of released hemoglobins.
(4) Myelin staining was achieved with Harris' hematoxylin when sections were delipidized and were differentiated in either acid-formalin or borax-ferricyanide.
(5) Crude borax ore and kernite ore induced weak transformation that was not dose-dependent and was not reproducible in another experiment.
(6) Laboratory bioassays with Culicoides variipennis larvae from Borax Lake, CA, indicated an LC90 of 16.8 ppb for pyrethrins at 23 degrees C. A field test in a pond adjoining the lake reduced adult C. variipennis emergence greater than 99% for over 30 days after treatment at a rate of 131 ppb pyrethrins.
(7) In the first case we used Bathurin in combination with borax at a concentration of 1.3% for both substances.
(8) Hepatitis B surface antigen (HBSAg) adsorbed from sera onto colloidal silica could be completely eluted through the use of 0.25% sodium deoxycholate in 0.01 M borax, pH 9.3, at 56 degrees C. The HBSAg recovered in the eluate represented 100% of that present in the original serum, and it was contaminated by only trace amounts of serum proteins (in decreasing amounts: beta-lipoprotein, immunoglobulin G, albumin).
(9) The size of the zone varies with the concentration of borax in the sample injected.
(10) By using of dehydration borax as purification agent during melting alloy was illustrated.
(11) Microheterogeneity of human serum albumin was studied by isoelectric focussing in ampholines and the borax-borate buffer-mannite system within the pH range 4.0--6.0 and by fractional precipitation in 3 M KCl.
(12) Dibucaine was dispersed in the gel which was prepared by gelation of the konjac flour in a borax solution at 60 degrees.
(13) To overcome these deficiencies, 3 changes in the method were made: (1) the defatting step was modified to use sodium lauryl sulfate in combination with borax for better defatting; (2) 40% isopropanol was substituted for 60% ethanol as the aqueous phase for cleaner papers; and (3) mineral oil was substituted for n-heptane to improve hair recoveries.
(14) Borax dust appears to act as a simple respiratory irritant and perhaps causes small changes in the FEV1 among smokers who are heavily exposed.
(15) Amongst the traditional medicines, it was noticed that sodium tetraborate (borax) and alum reduced appreciably the fluid requirement in many cases of acute childhood diarrhoea.
(16) pills" (with borax, methanol and cocaine) were delivered freely at the chemist's shop.
(17) A method is described, which is based on mordantings with a silver nitrate solution then with a borax solution and on an physical development.
(18) Flocculation from a homogenate previously clarified by the use of borax is best suited for large-scale operation.
(19) During the course of investigation of two infants with seizure disorders it was discovered that both had been given large amounts of a preparation of borax and honey which resulted in chronic borate intoxication.
(20) DYBH-bait formulations with about 17 per cent borax are very attractive and have a good effectivity.
Porcelain
Definition:
(n.) Purslain.
(n.) A fine translucent or semitransculent kind of earthenware, made first in China and Japan, but now also in Europe and America; -- called also China, or China ware.
Example Sentences:
(1) The colors of mixtures of dental opaque porcelains and modifiers were measured with use of the CIE L*a*b* uniform color space.
(2) Part 1 discusses the EsthetiCone, designed for use with multiple-unit restorations, which allows subgingival placement of porcelain for maximal esthetics.
(3) The results are in accord with the findings in an initial study by one of the present authors, in which the fillings were placed in denture porcelain teeth.
(4) The maximum stresses and strains in porcelain for the crowns with a conventional coping thickness (0.3 mm) and a reduced coping thickness (0.1 mm) were not significantly different.
(5) Endocardial fibroelastosis is characterized by a porcelain-like thickening of the endocardium, resulting in a marked increase in echodensity of the endocardium, as well as ventricular dilatation and aortic atresia.
(6) The etched porcelain laminate veneer is a new conservative treatment that offers a solution to fractured, discolored, and worn anterior teeth.
(7) It was found, with microscopic examination, that there is little or no diffusion of the stain into the underlying porcelain and that at a thickness of 22 microns the extrinsic stain layer is grossly evident to an observer.
(8) Porcelain glass transition temperatures and expansion values were derived from length-versus-temperature curves.
(9) Data received was converted to Munsell notation for evaluation of the dimensions of color, i.e., Hue, Chroma, and Value, as related to (1) shade differences, (2) thickness of porcelain, and (3) numbers of firings.
(10) Porcelain veneer restorations including preparations, impression materials, cast materials, refractory casts, handling of porcelain, the try-in, and the final luting are discussed.
(11) Clinical observations of porcelain restorations lead to the hypothesis that certain substructures tend to produce crowns with a lower than expected Value (brightness).
(12) Scanning electron microscopy was initially used to examine the surface configuration of porcelain prepared under various conditions.
(13) Dental porcelain emits some fluorescence under the action of ultra-violet rays.
(14) The bending strength and fracture toughness of the composite porcelains were examined.
(15) It is expected that porcelain veneer restorations will perform successfully in esthetic, conservative and abhesive dentistry.
(16) For example, many porcelain materials do not match their shade guide.
(17) Under four loading conditions, the tensile stress distributions on the ceramics crown were analyzed to evaluate the relations between three kinds of ceramics crown, which were an aluminous porcelain jacket crown, a feldspathic porcelain jacket crown and an Olympus castable ceramics (O.C.C.)
(18) The potential for porcelain fracture in debonding, however, is much increased and it is questionable whether bond strengths of this magnitude are required clinically.
(19) Techniques involving a cemented porcelain-fused-to-metal overcasting have often been successful in restoring the fixed partial denture to form and function.
(20) In children porcelain veneers provide a simple means of splinting traumatised anterior teeth which have coronal fractures either for the immediate or the long term.