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排序方式: 共有10000条查询结果,搜索用时 15 毫秒
891.
892.
EA Scodeller SG Tisminetzky F Porro M Schiappacassi A De Rossi L Chiecco-Bianchi FE Baralle 《Canadian Metallurgical Quarterly》1995,13(13):1233-1239
The principal neutralizing domain, IGPGRAF sequence, from the V3-loop of HIV-1 was inserted in two positions on the surface of the protein that makes up the capside shell of the insect Flock House Virus. The hybrid proteins were expressed in insect cells via recombinant baculoviruses. Three different hybrids were used as immunogens: two with a single copy of the insert in different positions of the carrier protein and a third with two copies of the insert at the same positions as before. All hybrid proteins induced strong and broad specific immune response in guinea pigs against different V3-loop sequences. However, only one of the hybrid proteins was able to induce a strong neutralizing response against MN and IIIB HIV-1 isolates. Our results demonstrate that a very short peptide sequence of HIV-1 can constitute a valuable immunogen able to induce a neutralizing response if presented to the immune system in the context of the FHV capsomer structure. 相似文献
893.
Sabate J.A. Jovanovic M.M. Lee F.C. Gean R.T. 《Industrial Electronics, IEEE Transactions on》1995,42(1):63-71
The analysis and design of an LCC resonant inverter for a 20 kHz AC distributed power system are presented. Several resonant converter topologies are assessed to determine their suitability for high efficiency power conversion, under resistive and reactive loads. Two LCC-resonant inverter designs were implemented. One with all switches operating with zero voltage switching (ZVS), and another with two switches operating with ZVS and two switches with zero current switching (ZCS). The experimental results are presented along with a performance comparison of the two versions 相似文献
894.
895.
Photovoltaic (PV) powered DC motors driving dedicated loads (e.g. water pumps) are increasingly used in the remote rural areas of many developing countries. The key to their success is simplicity (direct coupling, no DC-AC conversion, no storage batteries, etc.). Because of the relatively high cost of the PV array, the system designer is interested in maximizing its utilization efficiency. A PV powered DC motor can also be used to drive a three-phase self-excited induction generator (SEIG). This arrangement is useful as part of an integrated renewable energy system (IRES), which takes advantage of the inherent diversity of wind and solar energy in most developing countries to improve power quality. The SEIG is driven by a wind-turbine, DC motor, or both. Another advantage of this arrangement is its versatile control characteristics through the DC motor control. This paper describes a technique to maximize the utilization efficiency of the PV array by controlling the field current of the DC motor through a DC chopper 相似文献
896.
Summary The oblique flow of a viscous fluid impinging on a flat wall with suction or blowing is studied. It is found that when suction is applied the fluid penetrates the wall while blowing causes the shifting of the stagnation point. It is also found that this shifting depends upon the magnitude of the blowing. 相似文献
897.
N. Realdon M. Dal Zotto E. Ragazzi G. Dalla Fini 《Drug development and industrial pharmacy》1996,22(2):125-134
The release rate of a drug dissolved in the liquid phase of lipogels may be greatly affected by the type and concentration of gelling agent and by processing conditions and mechanical treatment of the ointment. These differences in release rate are reduced after application of mechanical stress comparable with the strain exerted on the ointment during application to the skin. Therefore, changes in the concentration of gelling agents used to achieve suitable consistency and manufacturing and packing processes that meet industrial and marketing requirements do not appear to exert a practical influence on drug availability after application to the skin. 相似文献
898.
899.
900.
The optimization of wet granulation in a 10-liter high-shear mixer was investigated using a nonclassical experimental mixture design. Hydroxypropylmethylcellulose, lactose, cornstarch, and microcrystalline cellulose were used as excipients of the granulate, while polyvinylpyrrolidone was used as binder. Besides the minimization of the number of experiments, the strategy applied takes into account the cost of each experiment. The introduction of such a modification allowed us to select an experimental matrix giving enough information with a relatively low number of experiments and at a minimum cost. 相似文献