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This study is based on precipitation samples from eight sites at the northern slope of the Qilian Mountains, combined with meteorological factors over the same period. Precipitation isotope characteristics, influence factors and the vapor sources of precipitation were analyzed, and the results show that:① The stable isotopes of precipitation in the study area show obvious seasonal changes, which are characterized by enrichment in the summer half-year and depletion in the winter half-year. The spatial precipitation

Based on hydrogen and oxygen stable isotopes in precipitation and meteorological data over Shaanxi-Gansu-Ningxia provided by the Global Network of Isotopes in Precipitation (GNIP) and in previous literature, the spatial and temporal variations of oxygen stable isotopes in precipitation and their driving factors were analyzed, the local meteoric water line (LMWL) functions were established. The results showed that the slope and intercept of the LMWL changed in the order of GansuShaanxiNingxia, with all of them being lower than slope and intercept of the Global Meteo-ric Water Line. The precipitation process of three provinces had been evaporated and fractionated to different degrees. The evaporation was enhanced along Ningxia, Shaanxi and Gansu. The δ依据全球大气降水稳定同位素观测网络(GNIP)和已有研究中陕甘宁地区的大气降水氢氧稳定同位素资料,并结合相关气象数据,分析了陕甘宁地区大气降水氧稳定同位素的时空分布特征及其影响因子,并建立了大气降水线方程.结果表明: 3省大气降水线的斜率、截距由小到大依次为:甘肃、陕西、宁夏,且均小于全球大气降水线方程的斜率、截距,表明3省的降水过程受蒸发作用影响程度沿宁夏、陕西、甘肃增强;陕甘宁地区大气降水中δ

This study was based on one complete hydrological year sampling of precipitation and meteorological data of the Shiyang River Basin in the Wuwei Station (1531 m a.s.l.), Minqin Station (1389 m a.s.l.), and Xidahe Station(2897 m a.s.l.) from July 2013 to July 2014. This paper aims to analyze temporal and spatial variation of stable isotopes in local precipitation, and discuss the impact of environmental factors during precipitation. The stable isotope evolution correlation with temperature, humidity, precipitation, vapor pressure, and average relative humidity is analyzed. The results show that:①During the study period, the stable isotope of precipitation showed significant seasonal changes, lower in the winter and spring, higher in the summer and autumn;②The monthly average D-excess of Wuwei Station is lower than that of Xidahe Station. In addition to the possibility of different water vapor sources, the high-altitude mountain areas are more affected by local recirculating water vapor, and the secondary evaporation under the clouds in low-altitude plain areas is stronger;③The stable isotope of precipitation in the basin shows a significant temperature effect, and the precipitation effect is reflected on the weather scale, which may be affected by leaching or monsoon circulation;④The

Based on the precipitation samples and meteorological data simultaneously collected during individual precipitation events at the Gulang (2085 m a.s.l.) and Anyuan stations (2700 m a.s.l.) in Gulang, this article analyzes the temporal variation and local meteroic water lines and discusses the relationship between precipitation stable isotopes and temperature and precipitation and relative humidity. The results show that:① Gulang and Anyuan have higher

Precipitation samples and meteorological data were collected simultaneously during individual precipitation events at Tuole station (3367 m a.s.l.) and Jiayuguan station (1658 m a.s.l.) in the Tuolai River Basin. A study of temporal variation, Local Meteoric Water Lines, and altitude change on precipitation stable isotopes was conducted. The relationships between precipitation stable isotopes and temperature, precipitation, average vapor pressure, and relative humidity were determined in order to explore the environmental significance of the stable isotopes at different altitudes in the middle reaches of the Qilian Mountains. The analysis indicated that the stable isotopes of the precipitation in Tuole and Jiayuguan station were characterized by pronounced seasonal variation, with Tuole having higher δ

Precipitation of the northwest China is different from that in other regions of China. The vapor reaches this region after long distance transportation with little precipitation, and the ratio of precipitation variation is large. Wushaoling at the east Qilian Mountains is an important divided line of climate in China. The east region of it is affected by South Asia and East Asia monsoon, while the west region of it is influenced by Westerly circulation. So ion combinations in precipitation are complex for the trajectories of water vapor transportation, the natural environments and the development levels of social and economy in different regions. Precipitation samples were collected at Heisongyi located at the east Qilian Mountains. Hydrochemical characteristics and sources of ions were analyzed by factor analysis, Enrichment factor analysis and back trajectory analysis. EC values in precipitation ranged from 29.20 to 892.00 μS·cm

The precipitation isotope data and meteorological data of eight stations provided by GNIP (Global Network for Isotopes in Precipitation) and two stations from the present study, combined with HYSPLIT model and water droplet evaporation model were used to examine the spatial and temporal distribution of precipitation δ利用GNIP提供的我国西北地区的8个站点和本研究的2个站点的降水同位素数据以及相应的气象数据,结合HYSPLIT模型和水滴蒸发模型,分析了我国西北地区降水δ

The data from typical boreholes in the southern Jianghan basin were modeled using the geothermal history simulation system of hydrocarbon-bearing basin, and the thermal history and burial history were reconstructed. Based on the thermal history, maturity evolution of the Lower Silurian source rocks was modeled. The results show that the basin was in a stable stage before Indosinian movement, the paleo-heat flow was between 50 mW/m~2 and 55 mW/m~2. After Indosinian period, the heat flow was elevated in the whole basin. In Yanshan period (155 Ma or so) , The heat flow reached their maximum values of ～72 mW/m~2 at 155 Ma in the north of the Qianbei Fault, The heat flows reached their maximum values of ～76 mW/m~2 at 40 Ma in the south of the Qianbei Fault. Since the late Himalayan epoch, the Jianghan basin was subjected to a deposition withering period accompanied by a cooling episode. In early Triassic, the maturity of source rocks in Zhijiang, Dangyang and Mianyang depression area first reached oil generation threshold, the maturity of source rocks increased rapidly during early Jurassic to early Cretaceous. The maturity was higher in the north of the Qianbei Fault than in the south of the Qianbei Fault. Based on this, in Late Cretaceous, the maturity of source rocks in the east area was higher than in the west area. The thermal evolution of source rocks terminated in the later Neogene. The heat flow history and Lower Silurian source rocks maturity evolution was calculated, which provides the basic data for source rocks evolution, hydrocarbon generation and expulsion prediction.

The precision of piezoresistive sensors is low between wide temperature range .The conditioning result isn’t ideal by analog approaches. Also the efficiency is very low. To improve this condition , a digital approach is introduced. It coverts sensors’ analog signal to digital value, and then uses polynomial and coefficients stored in singlechip to correct the digital value. At last , the singlechip coverts corrected digital value to analog signal to output. Its conditioning principle and calibration process is also described. We realized 4-to-20mA-current-loop-output of piezoresistive sensors using this aprroch. Calibration results show this method is efficient and low cost.

A wireless sensor network system is put forward that is applied in the field of monitoring wind load based on ZigBee technology. The hardware of the system adopts the SOC chip CC2530 as the core of the wireless communication model, and its front end CC2591 to extend the communication distance so as to reach the requirement of the specific application. In addition, the data acquisition model chooses pressure sensor monitoring wind load which connects to the microcontroller on the wireless communication model. The system software introduces sleep mode to realize the low power consumption when there’s no task in the system. The system is designed to monitor colossal buildings in typhoon situation, which will be applied to monitor the wind load on the cooling tower in power station soon.

A total of 90 precipitation samples were collected from individual precipitation events at the Qilian Alpine EcologyHydrology Research Station (Hulugou Station, 30 degrees 47'N, 90 degrees 58'E; 3 260 m a. s. l) located in the central Qilian Mountains from August 2012 to November 2013. All samples were analyzed for major cations (Na, K+, Ca2+ and Mg2+), anions (Cl- , NO3- and SO4(2-)) and conductivity. Precipitation EC values ranged from 2.26 to 482 μS x cm(-1) with an average value of 41.9 μS x cm(-1). The precipitation was of SO4(2-) -Mg(2+) -Ca2+ type, which contributed70% to the total ionic concentration. The same as the precipitation alkalinity, precipitation events occurred around summer showed lower concentrations, while it had higher concentrations in winter and spring with little precipitation and larger wind speed. Enrichment factor (EF), correlation and factor analysis indicated that regional crustal aerosols and species from central Asian and northwestern China arid regions brought by the westerly circulation were the major sources for these ions, some dust from human pollution were the secondary sources, and the contribution of sea salt was the least due to the long distance transport. These characteristics could be also confirmed by the correlation between ionic concentrations and metrological data in the study region. It is also interesting that the precipitation chemistry was different under the different atmospheric circulation: the monsoon precipitation, the interaction precipitation events ( influenced both by monsoon and westerly) and the westerly precipitation.

Rainwater samples were colleted from Lijiang City, China, in 23 May-2 July, 2006. Rainwater chemical compositions and sources were studied, using HYSPLIT model, ions tracer techniques, correlation and trend analysis. Total ionic concentration was dominated by SO4(2-) and Ca2+, which account for 65.5% and 15.6% respectively. Sort order of ions concentration is SO4(2-)Ca2+Cl(-)NO3(-)Na+K+Mg2+. Total anions concentration is higher than total cations concentration in 13 rainwater events. The ratio of SO4(2-) to NO3(-) varies from 7.2 to 37.1 and average value is 15.7, it reflected SO4(2-) made great contribution to rainwater acidity in Lijiang City. The correlation among ions is significant due to the atmospheric chemical process and similar ionic sources, and correlation coefficient between SO4(2-) and NO3(-) is 0.74. And what's more, the negative correlation of ionic concentration, precipitation and the average wind speed is also outstanding. The source of NO3(-), SO4(2-), K+ and Ca2+ is mainly land dust, and the non-marine source percent of NO3(-), SO4(2-), K+, Ca2+, Mg2+ and Cl(-) is 100%, 98.8%, 96%, 99.3%, 46.7% and 50.3%, respectively. The main reason of atmospheric environmental variation in Lijing City is pollution caused by economic actions. The pollutants from surrounding industrial parks input into Lijiang City by local circulation, and from industrial regions of Southern Asia, Southeastern Asia and Southeastern China input into Lijiang City by monsoonal circulation.