基于极值风速预测的台风数值模型评述

在沿海台风多发地区，高耸及长大建筑结构对于极值风速作用非常敏感，因此在结构的设计、施工与使用期间有必要合理估算结构设计使用期限内可能遭遇的台风极值风速。台风极值风速的估算不仅涉及台风风场的数值模拟，也包括风速样本的采集与统计分析过程。较系统地介绍了台风风场结构的各类数学模型，并对它们在不同使用目的背景下的适用性作了评述与比较。最后，基于越界峰值法探讨了工程场地一定重现期内台风极值风速预测的可行性。     

Dynamic pursuing ecological model concerning the nitrogen cycle in the environment of Chinese mainland

The paper gives a special dynamic pursuing ecological model on the bio-geochemical cycle of nitrogen in the whole range 9.6 million square kilometers of Chinese mainland, basing on the reservoir-content and flux-rate of nitrogen and among the four spheres: atmosphere, pedosphere, biosphere, and hydrosphere, and the law of bio-geochemical cycle of nitrogen, the model predicted the size of reservoir capacities and fluxes of nitrogen in each sphere. Through tested and verified, the model was proven reasonable and reliable.     

Simulating study on the effect of acid precipitation on forest soil weathering

The effect of acid rain on the forest soils in China was discussed on the basis of simulating studies. The soils were collected from five typical areas, including Chongqing in Sichuan Province and Guiyang in Guizhou Province, where there has been heavier acid rain in southwest China, and Huitong in Hunan Province, Zhouzhi in Shaanxi Province, and Xinglong in Hebei Province, all of which were selected as control. Field investigation and sampling were made in the typical forests in all the above five areas. The relationship between pH values in precipitation and rates of soil weathering, the difference between the rates of soil weathering in different areas, and the cause of such a difference, have been worked out. The prediction was also conducted on the supply dynamics of nutrient and toxic elements in various forest ecosystems which were affected by acid deposition in order to understand the long-term effects of acid precipitation on the forest ecosystems studied.     

From economic prosperity to ecological sustainability──A theoretical and practical concern of sustainable development in China

Ｆｒｏｍｅｃｏｎｏｍｉｃｐｒｏｓｐｅｒｉｔｙｔｏｅｃｏｌｏｇｉｃａｌｓｕｓｔａｉｎａｂｉｌｉｔｙ──ＡｔｈｅｏｒｅｔｉｃａｌａｎｄｐｒａｃｔｉｃａｌｃｏｎｃｅｒｎｏｆｓｕｓｔａｉｎａｂｌｅｄｅｖｅｌｏｐｍｅｎｔｉｎＣｈｉｎａＷａｎｇＲｕｓｏｎｇ，Ｈｕ...     

Effects of simulated acid rain on saplings of Pinus massoniana and Cunninghamia lanceolata

The effects of simulated acid rain with pH values of 6.63 (control, 4.5, 3.0, and 2.0 on saplings of Pinus massoniana and Cunninghamia lanceolate, were studied. The results showed that the pH of C.lanceolate, leaf sap and soil decreased as the acidity of rainfall increased. The acid rain with very low pH had significant effects on the photosynthetic rates per plant, but not on that of the per unit weight of dry leaves. The respiration rates of the two species were stimulated. Root and leaf boimass, but not stem biomass, were also reduced tremendously during a seven months period.     

Roleofscienceandtechnologyinenvironmentally sound urbanization in China

１　ＢｒｉｅｆｉｎｇｕｒｂａｎｉｚａｔｉｏｎｐｒｏｃｅｓｓｉｎＣｈｉｎａ１．１　ＴｈｅｉｍｐｏｒｔａｎｃｅｏｆｕｒｂａｎｉｚａｔｉｏｎｔｏＣｈｉｎａ○ｓｍｏｄｅｒｎｉｚａｔｉｏｎｄｒｉｖｅＴｈｅｆｉｒｓｔａｎｄｆｏｒｅｍｏｓｔｂｅｎｅｆｉｔｏｆｕｒｂａｎｉｚａｔｉｏｎｉｎＣｈｉｎａｓｈｏｕｌｄｂｅａｔｔｒｉｂｕｔｅｄｔｏｔｈｅｅｃｏｎｏｍｉｃｇｒｏｗｔｈ，ｗｈｉｃｈｉｓｔｈｅｐｒｉｍａｒｙｃｏｎｃｅｒｎｏｆｎｏｔｏｎｌｙｔｈｅｇｏｖｅｒｎｍｅｎｔ，ｂｕｔｔｈｅｏｒｄｉｎａｒｙｐｅｏｐｌｅａｓｗｅ…     

Sulfur dioxide-hydrogen peroxide relationships and acidification of precipitation in Guiyang area-a case study

-The concentrations of gas phase SO2, O3 and chemical composition of sequential rainwater samples were measured on 6/11/88 to 6/28/88 at some sites of Guiyang area. S (IV) was present in great excess of H2O2 in rainwater samples collected at residential sites of the city corresponding to high level of gas phase SO2. Considerable H2O2 in rainwater samples was observed in background air at suburbs. The evidence that clean rainwater samples were collected at 20km away from the city in 6/18/88 precipitation event revealed that the major process of acidification of the rain in the high polluted areas was below-cloud scavenging of trace gases. From a simulation calculation it was found that the rate of oxidation of S(IV) by O3 and by Mn2+, Fe3+ catalytic in high pH rainwater is significant, but for low pH the major SO42- is produced by the reaction of S (IV) with H2O2.     

GH4169合金超塑性挤压工艺的研究

此文通过挤压比为9:1的GH4169合金超塑性挤压工艺的研究,对GH4169合金的精密成形方式做了一些探讨。在自制的玻璃基润滑剂HLB03的使用下,T=1000℃、平均挤压速度y=2mm/min、最大单位挤压力P_(max)=561.7MPa时,得到了满意的挤压效果。     

Comparison of some atmospheric chemical modeling schemes

ＣｏｍｐａｒｉｓｏｎｏｆｓｏｍｅａｔｍｏｓｐｈｅｒｉｃｃｈｅｍｉｃａｌｍｏｄｅｌｉｎｇｓｃｈｅｍｅｓＳｈｅｎＪｉ，ＺｈａｏＱｉａｎｘｕｅＲｅｓｅａｒｃｈＣｅｎｔｅｒｆｏｒＥｃｏＥｎｖｉｒｏｍｅｎｔａｌＳｃｉｅｎｃｅｓ，ＣｈｉｎｅｓｅＡｃａｄｅｍｙ...