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1.
Wireless power transfer (WPT) via magnetic resonance coupling has been widely studied for vehicle applications, particularly the stationary and dynamic charging of electric vehicles. Our research group previously proposed a wireless in‐wheel motor to improve the reliability and safety of in‐wheel motors. Transmit power control is necessary to achieve stable WPT. We proposed a control method that uses a feedforward controller on the primary side and a feedback controller on the secondary side. However, the control method may cause shortfalls in the transmission power owing to modeling error, coupling coefficient variation, and signal communication delay. In this paper, we propose a novel feedback control method for the primary side based on conversion ratio estimation. The effectiveness of the proposed method was verified by simulations and experiments on the load current control of a constant voltage load and load voltage control of a constant power load.  相似文献   
2.
A fluorometric assay for lipid hydroperoxide in meats and fish was developed using pea peroxygenase, a hydroperoxide-dependent hy-droxylase. The freeze-dried microsome fraction of germinating pea seed was used as a peroxygenase source. Linear relationships between the hydroperoxide added (25 to 150 nmol) and fluorescence were observed with methyl linoleate hydroperoxide, linoleic acid hydroperoxide, triglyceride hydroperoxide, and phosphatidylcholine hydroperoxide. α-Tocopherol at levels equivalent to those in meats and fish did not affect the peroxygenase reaction. The assay was specific for hydroperoxides. The method enables determination of total lipid hy droperoxides in sample homogenates without extracting total lipids from retail meats and fish.  相似文献   
3.
A method for measuring the impact force in crash testing is developed. In this method, a mass is made to collide with the object being tested and the instantaneous value of the impact force is measured as the inertial force acting on the mass. To realise linear motion with sufficiently small friction acting on the mass, a pneumatic linear bearing is used, and the velocity and acceleration of the mass, the moving part of the bearing, are measured using an optical interferometer. The relative combined standard uncertainty in determining the impact force in a three-point bending test is estimated to be 0.5×10−2(0.5%) of the maximum value of the impact force.  相似文献   
4.
The microstructure of strontium titanate internal boundary layer capacitors at various stages in their processing was studied by transmission electron microscopy of rapidly quenched and normally cooled samples. Compositions containing excess TiO2, Al2O3, and SiO2 have a completely wetting liquid phase at the sintering temperature; during cooling TinO2 n −1, Magneli phases precipitate at multiple grain junctions. Diffused metal oxides and flux (Bi2O3, PbO, CuO, and B2O3) rapidly penetrate as a liquid phase along boundaries in postsintering heat treatment. This liquid phase disappears during slow cooling.  相似文献   
5.
The hydrothermal cracking of heavy oils, such as Canadian oil sand bitumen and Arabian heavy vacuum residue, as well as their model compound were performed over sulfided Ni/Al2O3 and NiMo/Al2O3 catalysts under 663~703 K and 6.0~8.0 MPa of hydrogen pressure in a batch autoclave reactor. According to the reaction mechanism of hydrothermal cracking, a small amount of free redical initiators, such as di-tert-peroxide, sulfur, etc., was added into the feed to generate free redicals at lower temperature, and obviously showed promotional effect on the conversion of hydrocarbons. The reaction mechanisms of hydrothermal cracking as well as the enhancing effect of initiators were studied by a probe reaction with 1-phenyldolecane as a molel compound. The hydrothermal cracking of hydrocarbon proceeded via free redical mechanism and hydrogenating quench. The initiators might easily generate free redicals under reaction temperature, these redicals might abstract H from hydrocarbon molecule and reasonably initiate the chain reactions, therefore, promote the conversion of hydrocarbon even at lower reaction temperature.  相似文献   
6.
This paper proposes a semicircular tubular linear synchronous motor called a “circular shaft motor” (CSM). A CSM can realize direct‐drive motion along the circumference of a circle. The design of the CSM is described. A magnetic field analysis was performed for the CSM model. The thrust characteristics of the prototype CSM system were measured in experiments. Angle control and force control were performed to demonstrate the utility of the developed CSM.  相似文献   
7.
Paratropomyosin is a minor myofibrillar protein which in freshly prepared myofibrils is exclusively localized at the A-I junction region of sarcomeres. We investigated the ultrastructural localization of paratropomyosin in intact and postrigor myofibrils by immunoelectron microscopy. Paratropomyosin was localized as two distinct stripes at the A-I junction in intact myofibrils. It also was localized at the position corresponding to the original A-I junction in thick filament-free myofibrils (I-Z-I brushes). However, following postmortem storage, paratropomyosin was found broadly distributed in thin filaments of myofibrils.  相似文献   
8.
Oils and fishy odor were extracted from the minced sardine meat with liquid carbon dioxide after dehydration with high osmotic pressure resin. This treatment resulted in higher quality minced sardine meat usable as “Surimi.” The lipids of the minced sardine meat defatted with liquid carbon dioxide was half that of undefatted meats; residual lipids were mainly composed of polar lipids such as phospholipids. Although soluble nitrogen and ATPase activity in sardine meat were decreased by dehydration and defatting, the Kamaboko-forming ability was present, and its flavor was improved after defatting. Moreover, sardine meat defatted with liquid carbon dioxide had good stability against protein deterioration and lipid peroxidation.  相似文献   
9.
High‐precision stages require high‐speed and high‐precision control to improve their production throughput and quality. However, their motion speed and accuracy are expected to reach a limit in the near future if the conventional high‐precision stage structure is used. Therefore, the authors designed and fabricated a “catapult stage,” which has a structure that can be decoupled into a fine stage and coarse stage. The catapult stage is different from conventional dual stages in which the fine stage is disturbed by the coarse stage because they contact each other. This paper proposes a novel control system design for the catapult stage and a control method that shortens the settling time by using final state control (FSC). So far, FSC has mainly been used for applications such as hard disk drives, for which the initial states are zero. However, it is important to consider the initial states for the catapult stage because the initial position, velocity, and acceleration of the catapult stage are not equal to zero. Simulations and experiments were performed to demonstrate the effectiveness of the proposed methods.  相似文献   
10.
常杰  椿范立  藤元薰 《石油化工》2002,31(11):871-874
采用间歇式高压釜反应器研究了加拿大油砂沥青和沙特重质减压渣油及其模型化合物十二烷基苯的加氢裂化反应,实验条件为5 0MPa、410~430℃、0~60min。以微小电热丝在反应器中很小的区域制造了局部高温,考察了其对加氢裂化的影响。结果表明,该方法促进了反应物中自由基的形成,提高了重质油及其模型化合物的转化率和中间馏分油的收率。  相似文献   
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