CXSD-30型山地钻机的改进与应用

CXSD-30钻机是一种便携式山地地震勘探钻井设备,可广泛应用于车载钻机无法作业的崎岖山地等地区,是一种水、气双循环的钻机。但是在黄土塬工区川道沟壑区域以及河套地带钻井时,潜水面以上使用气钻钻井、在潜水面以下就必须使用泥浆钻井,因此需要停止钻井将动力头气动中心管更换为泥浆钻井用的中心管。本文主要是介绍通过动力头中心管改造和增加球阀和三通,通过操控操作阀来实现气动钻井和泥浆钻井快速切换,从而解决了复杂地下构造特别是地下岩性变化较快的地区(河套砾石区)的钻井难题。

Influence of atmospheric circulation on precipitation in Altai Mountains

We analyzed the changes in precipitation regime in the Altai Mountains for 1959-2014 and estimate the influence of atmospheric circulations on these changes. Our study showed that during last 56 years the changes in the precipitation regime had a positive trend for the warm seasons(April-October),but weakly positive or negative trends for the cold seasons(November-March). It was found that these changes correspond to the decreasing contribution of "Northern meridional and Stationary anticyclone(Nm-Sa)" and "Northern meridional and East zonal(Nm-Ez)" circulation groups and to the increasing contribution of "West zonal and Southern meridional(Wz-Sm)" circulation groups,accordingly to the Dzerdzeevskii classification. In addition,it was found that the variation of precipitation has a step change point in 1980. For the warm seasons,the precipitation change at this point is associated with the reduced influence of "West zonal(Wz)","Northern meridional and Stationary anticyclone(Nm-Sa)" and "Northern meridional and Southern meridional(Nm-Sm)" circulation groups. For the cold seasons,a substantialincrease of "Wz-Sm" and a decrease of "Nm-Sa","Nm-Ez" circulation groups are responsible for the precipitation change in the two time periods(1959-1980 and 1981-2014).

A quasi-synoptic interpretation of water mass distribution and circulation in the western North Pacific II:Circulation

Using the data of conductivity-temperature-depth （CTD） intensive observations conducted during Oct-Nov. 2005, this study provides the first three-dimension quasi-synoptic description of the circulation in the western North Pacific. Several novel phenomena are revealed, especially in the deep ocean where earlier observations were very sparse. During the observations, the North Equatorial Current （NEC） splits at about 12°N near the sea surface. This bifurcation shifts northward with depth, reaching about 20°N at 1 000 m, and then remains nearly unchanged to as deep as 2 000 m. The Luzon Undercurrent （LUC）, emerging below the Kuroshio from about 21°N, intensifies southward, with its upper boundary surfacing around 12°N. From there, part of the LUC separates from the coast, while the rest continues southward to join the Mindanao Current （MC）. The MC extends to 2 000 m near the coast, and appears to be closely related to the subsurface cyclonic eddies which overlap low-salinity water from the North Pacific. The Mindanao Undercurrent （MUC）, carrying waters from the South Pacific, shifts eastward upon approaching the Mindanao coast and eventually becomes part of the eastward undercurrent between 10°N and 12°N at 130°E. In the upper 2 000 dbar, the total westward transport across 130°E between 7.5°N and 18°N reaches 65.4 Sv （1 Sv = 10-6 m3s^-1）, the northward transport across 18°N from Luzon coast to 130°E is up to 35.0 Sv, and the southward transport across 7.5°N from Mindanao coast to 130°E is 27.9 Sv.

Humble View on Soil Water Resources

Soil water is one of renewable water resources.Some properties of soil water concerning with its availability to plant are briefly described.An equation for estimating the amount of soil water resource is presented.Based on the evaporation demand of atmosphere,the evaluation coefficient for soil water resource is suggested.

Cyclic oxidation behavior of Fe-9Cr-1Mo steel in water vapor atmosphere

The cyclic oxidation behavior of Fe-9Cr-1Mo steel (9Cr-1Mo) in 10%H2O+90%Ar (volume fraction) atmosphere at 600, 650 and 700 ℃ for various time was studied. The oxidation mechanism of 9Cr-1Mo steel in 10%H2O+90%Ar atmosphere was discussed. The thermal stress was evaluated in two oxide layers to illustrate the spallation of the oxide layer. The experimental results indicate that there exists a duplex oxide scale with an outer layer of Fe2O3 and an inner layer of mixed (Fe, Cr)3O4 formed on 9Cr-1Mo steel during cyclic oxidation. Some cracks generated in both inner and outer oxide layers. Parts of oxide scales spalled from substrate during the cyclic oxidation. A higher tensile stress in the oxide layer is formed at the early oxidation stage than at the later oxidation stage during heating. This tensile stress results in the formation of cracks in the oxide layer.

青藏高原南北降水中δD和δ^(18)O关系及水汽循环

根据青藏高原南北不同地区降水及河水中δ D和δ18O, 建立了青藏高原从北到南降水中稳定同位素大气水线, 并解释了不同地区大气水线的差异性与水汽来源的关系. 分析了青藏高原南北降水中过量氘( d )的季节变化特征; 揭示了青藏高原降水和河水中d的空间变化, 研究发现青藏高原d在唐古拉山南北两侧显示出不同的变化特征.这种差异是与不同区域水汽来源或水汽循环有关.

Hydrological Responses to Climate Change in the Water Receiving Area of the Middle Route Project for South-to-North Water Transfer

Climate change will lead to a significant alteration in the temporal and spatial pattern variation in the regional hydrological cycle, and the subsequent lack of water, environmental deterioration, floods and droughts etc. And it is especially remarkable in semi-humid and semi-arid region. In this paper, the impacts of climate change on the hydrological cycle were analyzed for the Hai River Basin, a semi-humid and semi-arid basin and also the water receiving area of the middle route of South-to-North Water Diversion project. Meanwhile it is the most vulnerable to climate change. Firstly, the linear regression and Mann-Kendall non-parametric test methods were used to analyze the change characteristics of the hydrological and meteorological elements for the period from 1960 to 2009. The results show a significant increase in temperature, while precipitation decreases slightly, and runoff decreases drastically over the past 50 years. Secondly, the applicability of SWAT （Soil and Water Assessment Tool） model based on the DEM （Digital Elevation Model）, land use and soil type was verified in the basin. Results show the model performs well in this basin. Furthermore, the water balance model, Fu＇s theory and Koichiro＇s theory were used to calculate the actual evaporation, comparing to the simulated actual evaporation by SWAT model to validate the result for the lack of large-scale observed evaporation datasets. Possible reasons were also analyzed to explore the reasonable factor for the decline of the runoff. Finally the precipitation, temperature, runoff and evaporation response processes based on the IPCC AR4 multi-mode climate models and the verified SWAT model under different GHG emission scenarios （SRES-A2, AIB and B1） in the 21st century were discussed in three time periods： 2020s （2011-2040）, 20S0s （2041-2070）, 2080s （2071-2099）. Results show that there are systematic positive trends for precipitation and temperature while the trends for runoff and evaporation will differ among sub-areas. The results will offer some references for adaptive water management in a changing environment, also including adaptation of a cross-basin water transfer project.

Crawlspace heating system in detached house with insulated foundation

Two practical crawlspace heating systems introduced in detached houses have been chosen as a field study. One is the crawlspace warm air heating system and the other is the crawlspace hot water circulation system. Based on the field study result, by using the simulation sol, ware, THERB, the effectiveness of the crawlspace warm air heating system has been examined. The effect of the factors, such as the wind amount circulating between crawlspace and indoor space, foundation insulation condition, and heat amount into the crawlspace, on the indoor thermal environment has been analyzed. Based on these analyses, the measured crawlspace heating system can make the average temperature of the living room above 20℃. These two houses have excellent thermal environment. According to the simulating result, heat amount input into crawlspace, which can make comfortable indoor thermal environment, for every month in heating period has been roughly concluded, and they are 600 W in December and March and 800 W in February and January, respectively.

Brayton Power Cycles for Electricity Generation from Fusion Reactors

Brayton power cycles for fusion reactors have been investigated, using Helium in classical configurations and CO2 in a recompression layout. Thermal sources from the reactor have strongly constrained the cycle configurations, hindering use of a recuperator in Helium cycles and conditioning the outlet turbine temperature in CO2 ones. In both cycles, it is possible to take advantage of the exhaust thermal energy by coupling the Brayton to a Rankine cycle, with an organic fluid in the helium case （iso-butane has been investigated） and steam in the CO2 case. The highest efficiency achieved with Helium cycle is 38.5% using Organic Rankine Cycle and 32.6% with Helium alone. The efficiency changes from 46.7% using Rankine cycle to 41% with CO2 alone. The Helium cycle is highly sensitive to turbine efficiency and in a moderate way to compressor efficiency and pressure drops, being nearly insensitive to thermal effectiveness in heat exchangers. On the other hand, CO2 is nearly insensitive to all the parameters.

Theoretical and experimental investigation on a liquid-gas ejector power cycle using ammonia-water

The purpose of this paper is to investigate a novel power cycle using low-temperature heat sources such as oceanic-thermal, biomass as well as industrial waste heat. Both a reheater and a liquid-gas ejector are used in this ammonia-water based cycle. Energy analysis and parametric analysis are performed to guide the theoretical performance and experimental investigation is done to verify the theoretical results. The results show that the generator pressure, heating source temperature and turbine outlet depressurization made by the ejector can affect the cycle performances. Besides, the experimental thermal efficiency is much lower than the theoretical one on account of the heat losses and irreversibility. Moreover, the performance of liquid-gas ejector is affected by primary flow pressure and temperature.