摘要:
Switches of a switching circuit used to control operation of an electric motor such as in an electrically powered vehicle connect respective windings of the electric motor as a single phase inductor during battery charging. The inductor can then store inherent low frequency, second order ripple power and return that power to a load presented by a battery during battery charging to deliver substantially constant current. Storage of ripple power in the inductor allows the capacitance value, size, weight and cost of a filter capacitor of a power factor correction circuit providing input power to a battery charger to be reduced by an order of magnitude or more. Direction of current flow through the inductor is periodically reversed to avoid magnetizing the motor.
摘要:
Operation of a switching power converter having an output capacitor having a small equivalent series resistance (ESR) is stabilized and jitter reduced by sensing capacitor current with gain and combining the resulting signal with the output voltage signal to provide a feedback signal to control switching of the power converter. capacitor current can be sensed without interfering with operation of the filter capacitor by providing a branch circuit having a time constant matched to the output or filter capacitor but an arbitrarily high impedance so as to be effectively lossless. The gain provided in the capacitor current signal can be tuned to provide optimally short settling time after load transients; generally within one switching cycle. Matching of time constants and/or tuning of gain can be performed automatically.
摘要:
The present invention relates to the fields of chemistry and pharmaceuticals. Embodiments of the present invention provide transition metal complexes of amino acids. Transition metal complexes of embodiments of the invention according to Categories I, II, III, and/or IV may be used as antimicrobial, anti-malarial, and anti-cancer agents, as well as catalysts in chemical reactions. Such compounds of the invention are particularly useful for combating multi-drug resistance against a broad range of microbials (such as MRSA and mycobacteria), including gram positive and gram negative bacteria, as well as can be used as anti-cancer agents against bladder cancer, breast cancer, colon cancer, rectal cancer, endometrial cancer, kidney cancer, leukemia, lung cancer, melanoma, non-Hodgkin's lymphoma, pancreatic cancer, prostate cancer, and thyroid cancer, to name a few.
摘要:
A method is provided for ablating brain tissue of a living mammal comprising: placing first and second electrodes in a brain of the living mammal; applying a plurality of electrical pulses through the first and second placed electrodes which are predetermined to: cause irreversible electroporation (IRE) of brain tissue of the mammal within a target ablation zone; and cause a temporary disruption of a blood brain barrier (BBB) within a surrounding zone that surrounds the target ablation zone to allow material in a blood vessel to be transferred to the surrounding zone through the temporarily disrupted BBB. Such methods are useful for delivering large molecule material within a blood vessel of the brain across the BBB, where the large molecule is otherwise blocked by the BBB from passing through the blood vessel into the brain.
摘要:
A method for impedance measurement in a three-phase AC system is provided. The method includes injecting a shunt perturbation signal into the three-phase AC system and collecting a response to the shunt perturbation signal, and injecting a series perturbation signal into the three-phase AC system and collecting a response to the series perturbation signal. The response to the shunt perturbation signal and the response to the series perturbation signal are then transferred from abc coordinate to dq coordinates. At least one impedance of the three-phase AC system is calculated based on the response to the shunt perturbation signal and the response to the series perturbation signal.
摘要:
Embodiments of the invention provide regioselectively substituted carbohydrate and polysaccharide derivatives, such as cellulose esters, and methods for preparing them. Particular methods of the invention include deacylation of esters using tetrabutylammonium fluoride to obtain selective substitution at desired hydroxyl position(s) of the ester. Preferred is deacylation of an ester, which shows selectivity for removal of acyl groups from the ester of the secondary alcohols at C-2 and C-3, and which affords cellulose-6-O-esters with high regioselectivity by a simple one-step process employing no protective groups. Inventive regioselectively substituted cellulose esters can be prepared by such methods to obtain esters with the following anhydroglucose repeating units: wherein R1, R2, and R3 are each independently chosen from a hydrogen atom, and, whether substituted or unsubstituted, branched or unbranched, an alkanoyl group, an aroyl group, and a heteroaroyl group. In embodiments, the alkanoyl, aroyl and heteroaroyl groups can comprise from 1-20 carbon atoms.
摘要:
The present invention relates to infectious DNA clones, infectious chimeric DNA clones of porcine circovirus (PCV), vaccines and means of protecting pigs against viral infection or postweaning multisystemic wasting syndrome (PMWS) caused by PCV2. The new chimeric infectious DNA clone and its derived, avirulent chimeric virus are constructed from the nonpathogenic PCV1 in which the immunogenic ORF gene of the pathogenic PCV2 replaces a gene of the nonpathogenic PCV1, preferably in the same position. The chimeric virus advantageously retains the nonpathogenic phenotype of PCV1 but elicits specific immune responses against the pathogenic PCV2. The invention further embraces the immunogenic polypeptide expression products.
摘要:
High refractive index, melt processable polyphosphonates and methods for preparing the same are provided. These polymers are particularly useful for optical and ophthalmic parts, such as lenses. A method of preparing optical and ophthalmic lenses by injection molding the polymers of the present invention into the form of the optical or ophthalmic lenses is also provided.
摘要:
Three-phase interleaved resonant converters with integrated magnetics are described. In various examples, transformers are integrated into a transformer core of a converter. A primary side circuit includes a set of circuit segments corresponding to phases of the three-phase interleaved converter. Each of the circuit segments include an integrated winding component that provides a transformer primary winding and a resonant inductor connected in series.
摘要:
In one or more embodiments, a double damper is disclosed that may be used in an automotive suspension system. In one embodiment, a double damper includes a first damper having a first piston rod, a first gas chamber, a first compression chamber, and a first rebound chamber. The double damper further includes a second damper having a second piston rod, a second gas chamber, a second compression chamber, and a second rebound chamber. The first damper and the second damper are connected via a sleeve from which the first piston rod and the second piston rod extend at opposite ends.