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排序方式： 共有10000条查询结果，搜索用时 8 毫秒
181.
Burg B 《Medical economics》1994,71(9):32-6, 38-9
182.
183.
Rice B 《Medical economics》1995,72(19):42-4, 46-8
184.
Miller N 《Medical economics》1995,72(21):209-10, 212-4, 216-9
185.
Cepelewicz BB 《Medical economics》1995,72(13):43, 48, 50
186.
Rice B 《Medical economics》1995,72(7):32-4, 37-8
187.
188.
N. P. Rozanov N. V. Khanov A. M. Fedorkov 《Power Technology and Engineering (formerly Hydrotechnical Construction)》1995,29(4):237-241
| 1. | A pressure dangerous with respect to cavitation is observed in those places where the vortex core closely approaches the conduit wall (there are places where with formal conversion to the prototype vacuums m H2O are observed, actually the absolute values will be close to the vaporization pressure). |
| 2. | Delivery of air to ducts for the given spillway design reduces but does not remove the dangerous vacuum on the conduit walls. |
| 3. | Large vacuums are recorded both over the length of the outlet conduit and in the dissipation chamber. |
| 4. | The most effective (of those investigated) means of eliminating the vacuum on the conduit wall and in the dissipation structure are the installation of longitudinal ribs and transverse diaphragms in the outlet tunnel and delivery of air to the end of the swirler and dissipation chamber. |
189.
N. N. Kozhevnikov 《Power Technology and Engineering (formerly Hydrotechnical Construction)》1995,29(3):143-147
| 1. | An industrial procedure for electrofacing by a powder wire of special composition has been developed to produce a wear-resistant coating up to 5 mm thick on the components of suction dredges. An increase of 4–6 times is achieved in the time to failure of the faced components, while the cost of these operations does not exceed the price of the initial article. |
| 2. | It is expedient to use the facing procedure to strengthen new components under plant conditions and to restore worn parts at the site where the suction dredges are operated. The Scientific-Production Spetsstal' can perform work on electrofacing with the required materials, equipment, and technical accompaniment, and organize the strengthening of components at the plant. |
| 3. | The installation of a three-channel suction dredge with effective water protection of components from abrasive wear while eliminating overflow of slurry into the pump and increasing the efficiency of the unit on the whole is proposed. The proposal is recommended for development and implementation. |
190.
V. M. Bashmakov B. S. Sirozhev G. N. Petrov 《Power Technology and Engineering (formerly Hydrotechnical Construction)》1995,29(12):681-689
| 1. | In connection with the historically established economic conditions and existing agreements with neighboring countries, the cascade of Vakhsh hydrostation was designed on the basis of operating conditions in an irrigation regime and cannot provide Tajikistan's own need for power in the winter, the deficit of which is 4 billion kWh/yr. The traditional methods of solving this problem call for the construction of either an irrigation reregulator in the lower course of the river or a hydrostation operating in a power compensator regime in its upper course. Both these variants require vast expenditures of material and financial resources and provide an effect just due to one particular hydro development. |
| 2. | The natural conditions of Tajikistan created the unique possibility of increasing the effectiveness of the combined operation of the Vakhsh cascade by constructing a tunnel conduit and using the runoff of the Pyandzh River in operating the Vakhsh hydrostations. With minimum construction costs the power effect of the cascade in this case increases substantially since it is achieved due to the repeated use of Pyandzh River water at all stations of the cascade and without any detriment for irrigation. |
| 3. | Realization of the proposed project will increase the total power production of the cascade for all hydrostations specified by the scheme depending on the degree of streamflow regulation by the Pyandzh reservoir. The cost effectiveness of the proposed project is an order higher than that of the traditional variants. Even for the stations operating today on the cascade its effect is comparable to the effect of the Nurek hydrostation with respect to all indices. Here the total cost of the tunnel conduit together with the dam is an order lower than the cost of the Nurek hydro development. |