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Showing papers on "Chemical binding published in 1991"


Journal ArticleDOI
TL;DR: The ability of a chemical to bind toalpha 2u was used as a measure of biological activity to assess structure-activity relationships among the chemicals tested and known to cause the accumulation of alpha 2u and results so far suggest that binding is dependent on both hydrophobic interactions and hydrogen bonding.

68 citations


Journal ArticleDOI
TL;DR: Treatment of aldehyde-fixed pericardium with L-glutamic acid at pH 3.5 and storage in a nontoxic, bacteriostatic solution resulted in a lower degree of calcification in 63-day subcutaneous implants in rats, as compared with commercially available tissue.

59 citations


Journal Article
TL;DR: X-ray microanalysis (XRMA) is customized for investigations of the metabolic and detoxification strategies of heavy metals taken by marine organisms from polluted environments and can be tuned to observe the complex interactions which operate at all levels within and between the biota and polluted environments.
Abstract: X-ray microanalysis (XRMA) is customized for investigations of the metabolic and detoxification strategies of heavy metals taken by marine organisms from polluted environments. Sites of uptake, intracellular accumulation, transport and excretion are visualized, analysed and quantified. Cryopreparation techniques are required to prevent the translocation or loss from specimens of soluble metal species. In marine invertebrates, metals are detoxified by systems of chemical binding and intracellular compartmentalization. XRMA investigations have concentrated on marine molluscs and crustaceans and even within these restricted groups there are marked inter-species differences in the biochemical and cytological processes which reduce metal bioavailability. Some detoxification systems also protect the carnivores which ingest the metal-laden tissues of the prey. This results in the bioreduction of metals along a food chain. These processes are investigated by XRMA which can be tuned to observe the complex interactions which operate at all levels within and between the biota and polluted environments.

39 citations


Journal Article
TL;DR: In the mouse, several chemical mutagens have been found that cause their greatest genetic damage in late-spermatid and early-spermatozoa stages and that also bind very strongly to the protamine in these stages, although DNA breakage in these sensitive stages has been shown to increase.
Abstract: In mammals, variability in the genetic sensitivity of different germ-cell stages to mutagens could be the result of how much chemical reaches the different stages, what molecular targets may be affected in the different stages and whether or not repair of lesions occurs. In the mouse, several chemical mutagens have been found that cause their greatest genetic damage in late-spermatid and early-spermatozoa stages and that also bind very strongly to the protamine in these stages. Chemicals which are less genetically damaging to these stages have been found to have much less affinity for protamine. Furthermore, the level of chemical binding to DNA in late-spermatid and early-spermatozoa stages has not been correlated with the level of induced genetic damage, although DNA breakage in these sensitive stages has been shown to increase. This DNA damage is believed to indirectly result from chemical binding to sulfhydryl groups in protamine which prevents normal chromatin condensation within the sperm nucleus.

33 citations


Patent
12 Jul 1991
TL;DR: In this paper, a process of dewatering and agglomerating fine coal is described, which consists of treating an aqueous fine coal slurry with a chemical binding agent prior to filtration or drying.
Abstract: A process of dewatering and agglomerating fine coal. The process consists of treating an aqueous fine coal slurry with a chemical binding agent prior to filtration or drying. The preferred chemical binding agent is an emulsifiable process oil. The process results in more efficient dewatering and low dustiness of the treated coal.

18 citations


Journal ArticleDOI
TL;DR: In native polyacrylamide gel electrophoresis the albumins were visualised by iodine staining as a transparent spot against a brown background whilst the other proteins could not be visualised.
Abstract: Bovine serum, bovine serum albumins (delipidated or globulin free or Fraction V), rabbit serum, rabbit serum albumin, Atlantic salmon serum, purified Atlantic salmon serum albumin, human plasma alpha 2-macroglobulin, hemocyanin, trypsin inhibitor, bovine transferrin and bovine lactoferrin were examined by a novel method for specific visualisation of albumins. In native polyacrylamide gel electrophoresis the albumins were visualised by iodine staining as a transparent spot against a brown background whilst the other proteins could not be visualised. It is suggested that the brown background was due to penetration of the gel by iodine while the chemical binding of iodine by albumin produced a decolourisation reaction. This novel method provides a fast and simple approach to identifying serum albumin in polyacrylamide gels.

7 citations


Journal ArticleDOI
TL;DR: In this paper, an X-ray detector capable of measuring photons at an energy as low as 300 eV was used to perform PIXE analysis of light elements, and the fluorescence yields of N, O and F, that can be extracted from the measured Xray production, were found to deviate from theory.
Abstract: With an X-ray detector capable of measuring photons at an energy as low as 300 eV, it is possible to perform PIXE analysis of light elements. In combination with RBS the X-ray production of N, O and F as a function of the incident proton or He-ion energy can be quantified. The possibility of accurate quantitative analysis of low- Z materials is demonstrated. The fluorescence yields of N, O and F, that can be extracted from the measured X-ray production, are found to deviate from theory. The differences can be explained by the effects of chemical binding and multiple ionization on the physical processes involved in the particle-induced X-ray emission.

4 citations


Journal ArticleDOI
TL;DR: In this paper, the bond and molecular polarizabilities are studied for the gas-phase metal halides using delta-function potential model of chemical binding on the basis of quantum mechanical approach.
Abstract: The bond and molecular polarizabilities are studied for the gas-phase metal halides using delta-function potential model of chemical binding on the basis of quantum mechanical approach. The applicability of the model is demonstrated. The contribution of the polarity corrections for the metal halides is thoroughly investigated and it has been found that it plays a significant role for fluorides. Our polarizability calculations resolve the discrepancy about the conformation of the barium dichloride and mercury dichloride and favour the nonlinear structure. Due to lack of experimental results for most of halides of transition metals, the decision whether to incorporate polarity corrections or not remains uncertain at this stage: we must await measurements of more experimental values before we reach any final conclusion. The ionic bond orders have been used for the first time to investigate polarizabilities of monomers and dimers of alkali halides. The results for dimers reveal that polarity contribution is essential for the lithium halides dimers and not for other dimers. The computed results will be asset for the interpretation of experimental measurements.

4 citations


Patent
07 Jun 1991
TL;DR: In this article, the authors describe a strand mat having a fiber length of 5 mm or higher and bonded with a chemical binding agent and a polyolefin resin impregnated into the strand mat.
Abstract: PURPOSE:To prepare a reinforced resin sheet having an excellent impact resistance by impregnating a polyolefin resin into a strand mat bonded with a chemical binding agent CONSTITUTION:The title reinforced resin sheet comprises a strand mat having a fiber length of 5 mm or higher and bonded with a chemical binding agent and a polyolefin resin impregnated into the mat Usable fibers for the strand mat include inorg fibers such as glass fiber, carbon fiber, metal fiber, and ceramic fiber and org fibers such as polyvinyl alcohol fiber, polyarylate fiber, and polyamide fiber, the glass fiber being pref The surface of the fiber may be treated with a surface-treating agent (eg a silane coupling agent) to enhance the adhesion with a polyolefin resin The length of the strand less than 5 mm gives a reinforced resin sheet with an inferior impact strength, esp, Izod impact strength

2 citations


Patent
31 Jul 1991
TL;DR: In this article, the authors proposed to improve the binding force of fine grain binders and improve film strength by forming siloxane binding between the silica on surface layers of the fine grain and surfaces of grains for a tubular bulb.
Abstract: PURPOSE:To improve the binding force of fine grain binders and improve film strength by forming siloxane binding between the silica on surface layers of the silica fine grain binders and surfaces of grains for a tubular bulb and between the silica and a glass substrate face. CONSTITUTION:Phosphor grains 21 are stuck on a phosphor film 2 in multiple layers, and silica fine grain binders 22 with the grain size 0.5mum or below are provided between the phosphor grains 21 and between the phosphor grains 21 and the surface 11 of a glass substrate 1 to firmly bind them. Siloxane binding is formed between the silica on the surfaces of the binders 22 and the surface layers of the phosphor grains 21 and between the silica end the substrate surface 11, and they are bound by both the van der Waals force and chemical binding force. The silica fine grain binders 22 preferably have the grain size 0.01-0.004mum, and the compounding ratio of the binders 22 against the phosphor grains 21 is about 0.5wt.%.

2 citations


Patent
01 Jul 1991
TL;DR: In this paper, an organic or inorganic carrier having the ability to bind to a protein (eg apoaequorin) is swelled in a buffer solution and the swollen carrier is then suspended in a solution containing the protein having aequorin activity and reacted at 37 degC for 30min after completing the reaction, centrifugation is carried out to separate the resultant mixture into the carrier and a supernatant.
Abstract: PURPOSE:To obtain the subject immobilized protein, readily recoverable after use and useful as a biosensor, etc, by chemically binding a luminous protein having aequorin activity to an organic or inorganic carrier having the ability to bind to the protein CONSTITUTION:An organic or inorganic carrier (eg cellulose diethylaminoethyl ether) having the ability to bind to a protein (eg apoaequorin) is swelled in a buffer solution and the swollen carrier is then suspended in a solution containing the protein having aequorin activity and reacted at 37 degC for 30min After completing the reaction, centrifugation is carried out to separate the resultant mixture into the carrier and a supernatant and the carrier is subsequently washed with the buffer solution to afford the objective immobilized protein having the aequorin activity Furthermore, a protein, having the aequorin activity, obtained by cloning cDNA of a luminous jellyfish and prepared according to a technique of recombinant DNA is preferably used as the protein having the aequorin activity

Journal ArticleDOI
TL;DR: In this paper, four readily available fixing agents have been evaluated for possible use as stabilizers, i.e., wet cake, Portland cement alone, cement/silicate and cement/citrate mixtures.
Abstract: Los Angeles processes sewage sludge by dehydration and combustion at its Hyperion Treatment Plant. The ash product is usually classified as hazardous because of its heavy metal content, and four readily‐available fixing agents have been evaluated for possible use as stabilizers. The ash leachability was assessed before and after fixation using the California Waste Extraction Test. The leaching characteristics of dewatered wet‐cake sludge were also measured. While the fixing agents were found to decrease the leachability of ash considerably, ash and dewatered wet‐cake mixtures also immobilize metals to some extent. Chemical binding with fixing agents (i.e., wet‐cake, Portland cement alone, cement/silicate and cement/citrate mixtures) stabilizes the ash.

Patent
26 Feb 1991
TL;DR: In this paper, the authors present novel polymeric anionic molecules and novel negatively charged capture reagents comprising the reaction products of said anionic molecule and a specific binding member for use in separation techniques and assay procedures wherein said activated polymeric ion comprises a compound having the formula: wherein n is about 10 to about 500; z is about 1 to about 6; W is selected from the group consisting of H, Na, K, Li, amine salts, and derivatives thereof; and X is a reactive group or a structure having a reactive groups that enables the chemical binding of said
Abstract: This invention presents novel polymeric anionic molecules and novel negatively charged capture reagents comprising the reaction products of said anionic molecules and a specific binding member for use in separation techniques and assay procedures wherein said activated polymeric anionic molecule comprises a compound having the formula: wherein n is about 10 to about 500; z is about 1 to about 6; W is selected from the group consisting of H , Na , K , Li , amine salts, and derivatives thereof; and X is a reactive group or a structure having a reactive group that enables the chemical binding of said activated polymer to a specific binding member.

Patent
05 Jul 1991
TL;DR: In this article, a biologically active cement is obtained by mixing glass powder, containing 20-60wt.% Ca as a constituent ingredient, with an aqueous solution of ammonium phosphate as a curing solution, and further using ammonium dihydrogenphosphate or diammonium hydrogen phosphate as a phosphoric acid source of the curing agent solution.
Abstract: PURPOSE:To obtain a biologically active cement capable of bonding and fixing an artificial biological material to a biological bone in an early period and stably for a long period without causing inflammatory reaction by mixing glass powder containing calcium as a constituent ingredient with an aqueous solution of ammonium phosphate as a curing solution. CONSTITUTION:A biologically active cement obtained by mixing glass powder, containing preferably 20-60wt.% Ca as a constituent ingredient, preferably having <=44mum particle diameter with an aqueous solution of ammonium phosphate as a curing solution, preferably further using ammonium dihydrogenphosphate or diammonium hydrogenphosphate as a phosphoric acid source of the curing agent solution, regulating the quality thereof to about neutral pH6.0-8.5 and capable of firmly bonding and fixing an artificial biological material such as artificial bone or tooth to a biological bone in an early stage without causing inflammatory reaction in biological tissues and useful as a prosthetic material to defective parts of bones or teeth in addition to the aforementioned bonding without causing looseness even in use for a long period due to chemical binding to the biological bone.

Journal ArticleDOI
TL;DR: In this article, the role of energy on phase formation and film properties was investigated at room temperature as a function of ion energy in direct ion beam Nitridation and Oxidation of Si, Ge, and Si0.8Ge0.20.
Abstract: Direct Ion Beam Nitridation (IBN) and Oxidation (IBO) of Si, Ge, and Si0.8Ge0.2 were investigated at room temperature as a function of ion energy. The ion energies were selected between 100 eV and 1 keV to establish the role of energy on phase formation and film properties. Si0.8Ge0.2 films were grown by MBE on Si (100) and transferred in UHV to the ion beam processing chamber. The modification of composition and chemical binding was measured as a function of ion beam exposure by in situ XPS analysis. The samples were nitridized or oxidized using until the N or O 1s signal reached saturation for ion doses between 5×1016 to 1×1017 ions/cm2. Combined characterization by XPS, SEM, ellipsometry and cross-section TEM showed that insulating films of stoichiometric SiO2 and Si-rich Si3N4 were formed during IBO and IBN of Si at all energies used. The formation of Ge dielectric thin films by IBO and IBN was found to be strongly energy dependent and insulating layers could be grown only at the lower energies (E ≤ 200 eV). In contrast to pure Ge, insulating SiGe-oxide and SiGe-nitride were successfully formed on Si0.8Ge0.20.2 at all energies studied.

Journal ArticleDOI
TL;DR: In this article, the steady-state thermal neutron spectra in light water reactor fuel assemblies poisoned with non-1/v absorbers, such as cadmium, samarium, erbium, and gadolinium, in various concentrations have been computed at 298 K.
Abstract: This paper reports on the thermal neutron scattering kernel that explicitly incorporates the presence of chemical binding energy and the collective oscillations in the dynamics of water, the steady-state thermal neutron spectra in light water reactor fuel assemblies poisoned with non-1/v absorbers, such as cadmium, samarium, erbium, and gadolinium, in various concentrations have been computed at 298 K The calculated spectra are in reasonable agreement with the corresponding experimental spectra for realistic source terms