摘要:
Aqueous compositions containing compounds having the formula: ##STR1## wherein R is a straight- or branched alkyl residue containing 11 to 17 carbon atoms and X and Y are the same or different and each is an alkali metal, an alkaline earth metal, ammonium, an amine radical or hydrogen for selectively flocculating iron ions.
摘要:
A compound or mixture of compounds of the general formula: ##STR1## in which m and n may be 0 or 1 but both cannot be 1, R.sup.1, R.sup.2, R.sup.3, R.sup.4, R.sup.5 and R.sup.6 are independently H or CH.sub.3, X.sup.1, X.sup.2, Z.sup.1 and Z.sup.2 are independently hydrogen or straight or branched chain C.sub.1 -C.sub.4 alkyl; and the water-soluble inorganic or organic salts thereof, with the proviso that at least one of R.sup.1, R.sup.2, R.sup.3, R.sup.4, R.sup.5 must be CH.sub.3, and when m and n are both 0, R.sup.2 and R.sup.3 are each methyl and R.sup.4 and R.sup.5 have their previous significance, when added to an aqueous system imparts one or more of the following beneficial effects to be treated system:(a) the corrosion of ferrous metals in contact with the system is inhibited;(b) the precipitation of scale-forming salts of calcium, magnesium, barium and strontium from the treated aqueous system is inhibited; and,(c) inorganic materials present in the treated aqueous system are dispersed.
摘要:
A process for the removal of hydrogen sulphide from gases or liquid hydrocarbons, comprising contacting the gas or liquid hydrocarbon with an aqueous alkaline solution, preferably having a pH value of 8 to 10, comprising(a) an anthraquinone disulphonic acid or a water-soluble sulphonamide thereof(b) a compound of a metal which can exist in at least two valency states and(c) a sequestering agent comprising a compound of formula I: ##STR1## wherein R is an aliphatic residue containing from 1 to 12 carbon atoms and which is optionally substituted or interrupted by one or more hydroxy, or carboxyl groups; a carbonyl group, a phenyl group; or an aralkyl group containing 7 to 10 carbon atoms; and n is an integer of from 1 to 4; as well as salts, especially alkali metal and ammonium salts, and esters of compounds of formula I.
摘要:
Leakage currents across circuit components such as transistors are avoided by placing circuits into a low-leakage standby mode. The circuits are configured such that voltage differentials across leakage-prone circuit components are avoided when in standby mode. Various means are used to configure the circuits, such as configuration ports, data input lines, scan chains, etc. In embodiments containing reconfigurable devices, low-threshold transistors are used to implement the routing network.
摘要:
An integrated circuit has a field programmable circuit region arranged as a generally rectangular array of rows and columns of circuit areas. Some of the circuit areas each provide a respective processing unit for performing operations on data on at least one respective input signal path to provide data on at least one respective output signal path. Others of the circuit areas each provide a respective switching section; and the processing units and the switching sections are arranged alternately in each row and in each column. Each of a substantial proportion of the switching sections provides a programmable connection between at least some of the signal paths of those of the processing units adjacent that switching section in the same column and in the same row. A dense layout can be obtained with efficient local interconnections, especially in the case where one or more of the processing units has a plural-bit input and/or plural-bit output, and at least some of the signal paths are provided by respective plural-bit busses.
摘要:
A programmable logic device, such as a field programmable gate array or arithmetic array, comprises: a rectilinear array of logic cells 10 pitched with first and second general cell pitches P.sub.1, P.sub.2, respectively, in first and second axial directions, respectively, of the array; a first array of wires 12 each extending generally in the first direction between a respective pair of the cells which have a pitch of N.sub.1 .times.P.sub.1, where N.sub.1 is an integer greater than one, the first wire array having a pitch in the second direction generally equal to N.sub.2 .times.P.sub.2, where N.sub.2 is an integer greater than zero; and a second array of wires 14 each extending generally in the second direction between a respective pair of the cells which have a pitch of N.sub.1 .times.P.sub.2, the second wire array having a pitch in the second direction generally equal to N.sub.2 .times.P.sub.1. In order to minimize the number of cell locations with respect to the wiring to which each cell is connected, the wires in the first array have offsets in the first direction which are a first function of their position in the second direction, and the wires in the second array have offsets in the second direction which are a second function of their position in the first direction.
摘要:
A ring oscillator includes a first logic block having a first input connected to a specific point along a delay path, a first output and a second output, and a second logic block having a first input connected to the first output of the first logic block, a second input connected to the second output of the first logic block, a third input connected to the end of the delay path, and a first output connected to the beginning of the delay path. The first logic block is arranged to alternately switch its first output and second output from logical HIGH to logical LOW, and vice versa, every time a rising edge is input into its first input. The second logic block is arranged to alternately select its first input and its second input every time a rising edge is input into its third input.
摘要:
Analytical methods using hydrogen/deuterium exchange are provided which reduce or eliminate the back-exchange of deuterium for hydrogen. The methods, which are useful in protein and peptide mapping, include the steps of (a) providing a peptide or protein comprising a solvent accessible hydrogen; (b) exchanging the solvent accessible hydrogen for a deuterium; (c) separating the peptide or protein with supercritical fluid chromatography; and (d) analyzing by mass spectrometry the mass of the separated peptide or protein. Supercritical fluid chromatography enables the observation of fast exchanging hydrogen atoms missed using conventional liquid chromatography methods.
摘要:
A drill bit is disclosed for use in a percussion drilling apparatus of the type for boring into the earth. Embodiments of the drill bit comprise an elongate body with a first end, a second end, and a longitudinal surface extending between the first and second ends. Embodiments further comprise a plurality of splines on the longitudinal surface of the drill bit, with at least one of the plurality of splines comprising an apex, a root, and a planar surface between the apex and root. In preferred embodiments, the planar surface is oriented at an angle between 10 and 45 degrees to a plane extending from a center of the drill bit to a midpoint of the apex.
摘要:
A heterogeneous array includes clusters of processing elements. The clusters include a combination of ALUs and multiplexers linked by direct connections and various general-purpose routing networks. The multiplexers are controlled by the ALUs in the same cluster, or alternatively by ALUs in other clusters, via a special purpose routing network. Components of applications configured onto the array are selectively implemented in either multiplexers or ALUs, as determined by the relative efficiency of implementing the component in one or the other type of processing element, and by the relative availability of the processing element types. Multiplexer control signals are generated from combinations of ALU status signals, and optionally routed to control multiplexers in different clusters.