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101.
香港海滨地区的存亡
自1840年开始的填海工程成为调节香港城市发展的核心策略为城市继续发展提供了必需的土地。回顾以往,对于另一个艰巨的挑战来说,这是一种简单的解决方案:香港的山地岛屿地形被证实大部分无法满足城市住宅和商业建筑发展的需要。它还要持续提供额外的建设用地,满足快速增长的人口所需的基础设施和道路:居住建筑,经济发展需要的劳动力空间和燃料都靠填海获得。填海工程发挥着作用,没有其他选择。这种发展模式是香港特有的,导致九龙和香港的海岸线不断靠近从原来的近2000m到现在的800m。 相似文献
102.
Results from six tests, finite element simulations and a synthesis of previous test programs on slotted end bracing connections are presented. The main objective of the research is to examine the deformation capacity of these connections, with the ultimate objective of minimizing the requirement for net section reinforcement that is often inconvenient from the perspective of fabrication. The experiments and simulations feature commonly used pipe specimens and end details. The main parameters investigated include the gusset plate thickness, the slot length and introduction of a wrap-around weld that eliminates the reduced section at the edge of the gusset plate. The results indicate that even without reinforcement, the connections offer adequate to excellent deformation capacity if they are provided with the wrap-around weld or if the net section strength is larger than the gross yield strength. This may be achieved in situations where shear lag in the connection is minimal, and where the area reduction due to the slot is small relative to the gross area. Design considerations are presented along with limitations of the study. 相似文献
103.
Kriksunov É. Z. Perel'muter A. V. Perel'muter M. A. Cementsov A. I. Fedorovskii V. G. 《Soil Mechanics and Foundation Engineering》2002,39(1):10-12
Soil Mechanics and Foundation Engineering - 相似文献
104.
Kudashev S. V. Kondrasenko A. A. Maiulev A. N. Babkin V. A. Belousova V. S. Andreev D. S. Zheltobryukhov V. F. Kuznetsova N. V. 《Fibre Chemistry》2022,53(5):291-295
Fibre Chemistry - Modification of polycaproamide by 1H,1H,13H-trihydroperfluorotridecan-1-ol immobilized on montmorillonite produced an F-containing polymer composite. The structure of the... 相似文献
105.
Fibre Chemistry - Under modern conditions the creation of materials for sanitary hygiene and medical products based on cellulose is of paramount importance. Development and improvement in this area... 相似文献
106.
Demchuk V. A. Kalinichenko B. B. Bogomazova E. V. Rozhdestvina V. I. 《Glass and Ceramics》2022,78(9-10):378-381
Glass and Ceramics - A catalyst was developed in the form of a composite based on a zeolite matrix modified with titanium nanoparticles based on zeolite raw materials from the Kulikovskoe deposit... 相似文献
107.
Guseva T. V. Tikhonova I. O. Tsevelev V. N. Shchelchkov K. A. Averochkin E. M. 《Glass and Ceramics》2022,78(9):397-401
Glass and Ceramics - A system for technological regulation of adverse environmental impacts (AEI) that is based on the best available technologies (BAT) was analyzed. The expediency of updating the... 相似文献
108.
Pyatigor A. D. Myshelovka L. V. Vokhmyanina K. A. Sotnikova V. S. Kubankina A. A. Grigor’ev Yu. V. 《Glass and Ceramics》2022,79(1-2):62-64
Glass and Ceramics - The results of experimental studies of the transmission of 12 and 15 keV electron beams through tapered glass macro-capillaries are presented. Measurements showed that there is... 相似文献
109.
A power-supply unit for pulsed lasers that are pumped by low- and medium-power flashlamps with long pump pulses that does not require a capacitive storage unit is described. The pump-pulse duration is limited by the radiation and thermal stability of the active elements and pump lamps. A functional diagram of the power-supply unit and a circuit diagram of its power system are presented. The basic parameters and elements of this unit, as well as the results of using a laser with the described power supply in experiments, are presented. 相似文献
110.
A. V. Bakhmutova V. A. Ditlov M. A. Kolyvanova 《Instruments and Experimental Techniques》2018,61(5):730-739
The numbers of detected ions and the beam density dispersions at different depths of plate locations that also cover the Bragg peak region were determined by automatically searching for etched micropores in photographs of surfaces of CR-39 plastic plates exposed to 12C ions with an energy of 216 MeV/amu in a chamber for radiobiological investigations at the TWAC–ITEP accelerator–accumulator facility. A computer method for seeking etched micropores along latent ion tracks in an exposed plastic is described. Frequency distributions of detected ions over microscopic areas of each surface for eight plates have been obtained and compared using a Gaussian function. 相似文献