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The Baiyangdian Lake is located in Xiongan New Area, which has a fragile ecological environment and a shortage of water resources. Lake evaporation is one of the main discharge of the Baiyangdian Lake, and research on lake evaporation is of important practical significance and scientific value for understanding lake water circulation and evaluating ecological water demand and for recovery of lake ecological function. However, the actual observed data on evaporation in the Baiyangdian Lake is limited, so it is usually estimated by converting the data of nearby land observation stations or empirical models, which cannot accurately estimate the lake evaporation because of large calculation error. In this work, in-situ experiments were carried out in the Baiyangdian Lake. This study established an E601 evaporation station and a 20 m2 evaporation pool to observe the lake evaporation at the center of the Baiyangdian Lake, and an automatic weather station was established simultaneously to get meteorological data. The correlation between evaporation by E601 evaporation station and meteorological factors is analyzed by methods of correlation analysis and multiple linear regression model. The evaporation of the E601 evaporation station is compared with the data of the 20 m2 evaporation pool and the simulated evaporation. The results indicate that in the Baiyangdian Lake in summer, the diurnal variation of lake evaporation is intense, ranging from 0.4 mm/d to 6.6 mm/d, and the maximum evaporation occurs in June, but decreases with the increasing rainfall from July to August. Evaporation of lake water is more affected by radiation and humidity. The evaporation of 20 m2 evaporation pool is taken as the evaporation of lake water. The observed evaporation of E601 evaporation station is higher than the actual evaporation of Baiyangdian Lake, which can be used to estimate lake evaporation more accurately by local evaporation conversion coefficient. In this experiment, the evaporation conversion coefficient between the 20 m2 evaporation pool and the E601 evaporation station is about 0.98, which is slightly greater than the previous studies. The results of this study provides a basic basis for the calculation of water surface evaporation in the Baiyangdian area.

In a pumping test, recording and analysis of the dynamic water level data are of great significance in the calculation of hydrogeological parameters. In recent years, automatic water level monitors have been widely used in pumping tests, and the pressure head change value of the pressure sensor is regarded as the drawdown of water level. Due to the water flowing in the well pipe can cause head loss, the automatic water level monitors at different positions can also obtain different drawdowns of water level, which are different from the drawdown of well water surface level measured by the traditional method and also has some influence on the calculation of hydrogeological parameters. Therefore, it is urgent to carry out experimental researches on how to place automatic water level monitors reasonably and how to apply the drawdown data from the automatic water level monitors in hydrogeological parameter calculation. In the large thickness aquifer area of Quaternary system in the Heihe River Basin, a typical single-layer test hole and a multi-layer test hole are selected for experimental studies, in which the multi-layer hole is a pumping test hole with the same diameter layered by the Parker technology. Under the dynamic water level, automatic water level monitors are placed in the upper, middle and lower parts of the pumping test section and the upper and lower parts of the pump for systematic data collection and analysis. The results show that in the pumping test, water flowing in the well pipe can cause head loss and velocity head difference, so the pressure head change value obtained by the automatic water level monitors at different positions are different. The well loss values at different parts of the wellbore are measured in this test. At the inlet of the submersible pump the well loss value is the largest, and decreases with the increasing distance from the submersible pump. To avoid the influence of bigger well loss on parameter calculation, the automatic water level monitors are preferably placed in the upper part of the pump close to the dynamic water level. When the steady flow formula is used to calculate the hydrogeological parameters in the single hole pumping test, the drawdown of the automatic water level monitor contains well loss, which cannot be ignored and needs to be deducted by the multiple drawdown pumping tests data. Moreover, the data analysis of the automatic water level monitors at different positions can provide a basis for better understanding the head loss in the well.

Rainfall and irrigation are important sources of recharge for shallow groundwater in the middle reaches of Heihe River . There is no mature monitoring method and empirical data for evaluating infiltration recharge by introducing empirical parameters for a long time. In this paper, artificial bromide tracer method is used to study groundwater infiltration under different irrigation conditions and different depths in the middle reaches of the Heihe River. The results show that under the condition of rainfall in the study area, the annual average transport distance of the peak content of bromine ion in the vadose zone is 21.25 cm, the annual average recharge is 11.93 mm, and the infiltration recharge coefficient is 0.1. Under the condition of large irrigation amount, the average annual migration distance of the peak content of bromine ion in the vadose zone is 86.51 cm, the average annual recharge is 148.7 mm, and the infiltration recharge coefficient is 0.16. Under the condition of small irrigation amount, the average annual migration distance of the peak content of bromine ion in the vadose zone is 46.35 cm, the average annual the downward zone of unidirectional infiltration of water in the unsaturated zone, which is generally suitable in the recharge is 53.81 mm, and the infiltration recharge coefficient is 0.07. Under drip irrigation, the average annual moving distance of the peak value of bromine ion content in the vadose zone is 41.72 cm, the average annual supply is 52.6 mm, and the infiltration recharge coefficient is 0.11. Artificial bromide tracers should be placed in northwest inland basin more than 3 m. The results can provide parameters for the evaluation of groundwater resources in the Heihe River Basin, which is of great significance for scientific understanding of groundwater resources and rational development and utilization in northwest inland basins.

The quantity of recharge of groundwater lateral flow from mountainous areas to plain areas is a long-term controversial and unresolved problem, which is always estimated to be too small or too large in arid inland basins in northwest China. Based on previous studies, this paper uses the technical methods of geological and hydrogeological investigation, geophysical exploration, drilling, pumping test, groundwater dynamic observation, hydrochemical test, basin groundwater level measurement and comprehensive study to identify the geological structure contact relationship, stratigraphic lithology contact relationship at the southern mountain-basin transition zone of the middle reaches of the Heihe River Basin, and the Cretaceous weathering crust aquifer structure and hydrogeological parameters at the Liyuan estuary. Through the analysis of the surface water and groundwater transformation relationships of different watershed levels in the mountainous areas, the recharge zones of groundwater lateral flow from the mountainous areas to the plain areas are divided into the large and medium-sized river valley recharge sections and shallow mountain recharge sections composed of small and micro rivers and gully groups. The exploration data of the river valley recharge sections are abundant, and the Darcy section flow method is used to calculate the recharge quantity. In view of the fact that the recharge section of the shallow mountain belt extremely lacks the exploration data, the runoff of the Liyuan estuary section is used as a reference. The estimation method of recharge of the groundwater lateral flow from the mountainous areas in the shallow mountain belt to the plain area is constructed with three variables of lithology, catchment area and precipitation. The results show that the quantity of recharge of groundwater lateral flow from the southern mountainous area to the plain area in the shallow mountain zone of the middle reaches of the Heihe River Basin is 0.40 × 108 m3/a, and that of bedrock in the valley sections is 0.07 × 108 m3/a. The quantity of recharge of groundwater of the Quaternary sediments in the valley sections is 0.30 × 108 m3/a. The sum of the three recharges is 0.77 × 108 m3/a, accounting for 3.0 % of the basin groundwater resources. This method provides an example for the estimation of the recharge of groundwater lateral flow from the mountainous areas to the plain areas in the northwest inland arid basins.

Temperature is an inherent property of groundwater.Groundwater temperature field and dynamic characteristics are objective manifestations of groundwater flow system.Based on multi-point, long series and high precision groundwater temperature monitoring data, the characteristics of shallow groundwater temperature distribution and dynamic type of water temperature in Jiuquan East Basin are studied, in order to reveal the relationship between the characteristics of shallow groundwater temperature field and groundwater flow system under the influence of human activities such as groundwater exploitation in northwest inland basin.The results show that the shallow groundwater temperature ranges from 9.33℃ to 20.77℃, and the average water temperature is 13.54℃.From the recharge area to the discharge area, the shallow groundwater temperature increases gradually along the direction of groundwater runoff, and the average groundwater temperature in January is higher than that in July.The comparison of different groundwater flow systems with similar circulation depth shows that the shallow groundwater temperature is negatively correlated with groundwater dynamic conditions.The average groundwater temperature of the water flow system with large surface water recharge and strong hydrodynamic conditions is lower, and that of the water flow system with small recharge and weak hydrodynamic conditions is higher.The temperature dynamics of shallow groundwater are affected by human activities such as natural groundwater circulation and groundwater exploitation.From groundwater recharge area to oasis area in the middle reaches and drainage area in the lower reaches, the temperature dynamic of shallow groundwater can be divided into four basic types, which are river recharge type, water temperature stability type, groundwater exploitation related type and sinusoidal fluctuation type respectively.

Abstract Background To compare the clinical outcomes of stereotactic body radiation therapy (SBRT) and fractionated radiation therapy (FRT) for primary liver cancer with portal vein tumor thrombus (PVTT). Methods This retrospective study included 36 patients who underwent SBRT and 36 patients who underwent FRT from August 2016 to June 2018. Patients were evaluated for short-term efficacy, long-term efficacy, AEs, and quality of life before and after treatment. Results With a median follow-up of 28.8 months (26–36 months), 27 patients survived in the SBRT group while 19 patients survived in the FRT group. The survival rate in the SBRT group was statistically higher than that of the FRT group after 6 months (80.56% vs. 58.33%; P = 0.041), 12 months (77.78% vs. 55.56%; P = 0.046) and 24 months 75.00% vs. 52.78%; P = 0.049). The median whole survival time of the SBRT group was 13.3 months (95% CI 12.83–13.97), which was statistically longer than 9.8 months in the FRT group (95% CI 8.83–10.97, P

Abstract Background This study compared a co‐ablation (CA) system, which is a novel ablation device, with an argon‐helium cryoablation (AHC) system. We aimed to compare the efficacy and safety of CA and AHC for the treatment of stage III–IV non‐small cell lung cancer (NSCLC). Methods We conducted a multicenter randomized controlled trial (RCT) to determine whether CA was noninferior to AHC. The primary efficacy endpoints were the iceball coverage rate (ICR) and the disease control rate (DCR) one month after treatment. Noninferiority was declared if the lower limit of two‐sided 95% confidence interval (CI) was less than 10%. The ICR and DCR were identified by logistic regression. Treatment safety was assessed. Results A total of 81 patients underwent randomization (41 assigned to the CA and 40 assigned to the AHC groups)and transthoracic ablation. The ICRs in the CA and AHC groups were 99.24% ± 2.18% and 98.66% ± 3.79%, respectively. Central lesions were associated with an increased risk of an incomplete ICR. The DCRs in the CA and AHC groups were 97.6% and 95%, respectively. A smaller lesion area in the CA group was significantly correlated with a better DCR. The rate of complications was 29.26% in the CA group and 30% in the AHC group. (P = 0.943). There was less probe usage per patient in the CA group. Conclusions We determined that CA is noninferior to AHC in terms of efficacy and safety for the treatment of stage III–IV NSCLC. A smaller lesion area in the CA group was significantly correlated with a better DCR. Key points CA was noninferior to AHC for stage III–IV NSCLC.

The groundwater stored in the aquifer is a kind of moving fluid, which is continuously distributed in space and can transmit pressure.It is driven by the potential energy difference to move from high to low head.Usually in the recharge area (high head), the groundwater moves vertically from top to bottom, while in the drainage area (low head), the groundwater moves from bottom to top.The movement of groundwater in aquifers is like the same life process, in which it always moves from the source to the sink in the direction of energy reduction, whether it is in a single or multiple permeable rock formations.Hydrogeological stratified exploration technology (HSET) makes it possible to monitor different depths of groundwater elements such as head, temperature and quality in the vertical direction, so as to realize the comparison of groundwater elements between the vertical points of multi-layer aquifer rock formations.At the same time, HSET can judge the potential source and sink conditions of different vertical sections of a full well or a single well, laying a foundation for finely describing the spatial movement of groundwater flow and delimiting the groundwater system.This paper discusses the principle, system structure and function of groundwater layered exploration based on the theory and experimental observation of groundwater flow system and expounds the application method of layered exploration technology in the identification of groundwater recharge or discharge area in Zhangye Basin.