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The task of the fiber transport channel (FTC) is to transport the fibers from the carding roller to the rotor. Its geometric position in the spinning machine has a strong influence on the characteristics of the airflow field and the trajectory of the fiber motion in both the rotor and the FTC. In this paper, a three-dimensional pumping rotor spinning channel model was established using ANSYS-ICEM-CFD software with three different positions of the FTC (positions a–c). Further, the simulations of air distribution were performed using Fluent software. In addition, the discrete phase model was used to fit the fiber motion trajectory in the rotor. The simulation results showed that among the three types of FTC, position b is the optimal condition. The gradients of airflow velocity in the channel at position b were greater than those of the other two positions, which is conducive to straightening of the fiber.

This research aims to explore the dynamic transport of water and salt in soil under different irrigation modes and disclose the desalting effect of different irrigation factors in inland arid irrigation areas. Jingdian Irrigation District in Gansu Province, which is located in the arid region of Northwest China, is selected as a typical experimental area. Soil water and salt dynamic migration model is constructed based on HYDRUS-2D software, and field irrigation experiments are designed according to actual irrigation conditions in crop growth period. The model is used to simulate the salt transport process between saturated soil and unsaturated soil as well as the effects of different irrigation quotas, irrigation rounds and quota allocations on soil desalting. Through simulation, the vertical movement pattern of water and salt in the soil of the test area is analyzed, and the optimal design of the soil desalting irrigation plan is carried out. The results demonstrate that: after two-round irrigation, the average soil salinity of the tillage layer at each test points decreases significantly under evapotranspiration; the infiltration of irrigation water has an obvious impact on soil desalting; the deviation between the simulated and the measured value is less than 0.5%, which proves the model fitting result reliable; with fixed irrigation cycle and times, the soil desalting efficiency is higher when the irrigation quota falls in the range of 4000 ~ 6000 m3/hm2; when the first round of irrigation water only saturates the moisture content and gradually increases the irrigation quota in the subsequent rounds, it is more conducive to the dissolution and discharge of soil salinity. In summary, the results of this study can provide technical support for the protection of water and soil resources, as well as the improvement of saline-alkali land in inland arid irrigation areas.

In order to facilitate watershed management, we developed an expansive river health assessment method based on a fuzzy matter-element extension model in this study that developed based on the transitive hierarchies and degree of membership from improved fuzzy optimization theory. Eight characteristics of river flow, namely, the morphology, flow, water quality, river habitat, aquatic organisms, riparian zone, flood control safety, and level of the water supply, were investigated in this study to establish a system of indices to assess river health. We apply the above method to a river health assessment in the Luanhe River as sub-healthy. The results show that the method is accurate for the river health assessment compared with the actual conditions in Luanhe river. Moreover, the river health assessment method described in this study covers the different health states of river ecosystems, including the natural function and the social service function of a river. It is a reasonable river health assessment method that can evaluate river health status systematically, comprehensively and accurately. Therefore, this method is reasonable and effective and can be used to assess the ecological health of rivers in other regions.

Obtaining hydraulic properties is crucial for describing the transport of groundwater and pollutants in the faults area. In this way, the spatial distribution of hydraulic conductivity plays a major role in expressing the heterogeneous flow and non‐Fickian behavior of solute transport which both are common in nature. However, the existing methods are focusing on obtain the mean value (1D) of the aquifer’s hydraulic conductivity, and there are certain challenges in obtaining the spatial distribution (2D) of the hydraulic conductivity. Thus, in this study, a novel method was proposed that combines electrical resistivity tomography (ERT) with pumping test data to obtain the spatial distribution of hydraulic conductivity for metamorphic rock and granite fault zone in the Xinchang region of Beishan, China. The hydraulic conductivity of an aquifer was obtained using data from 30 pumping tests for seven pumping wells, and the results were fitted using the ERT and used to determine the aquifer resistivity at the respective positions. The measured resistivity and hydraulic conductivity were fitted to obtain a correlation (R-K). The hydraulic conductivity for metamorphic rock with a small hydraulic conductivity was better fit by an exponential (R2 = 0.97) than a linear or power law. The hydraulic conductivity calculated using the R-K correlation has an error of less than 10.50% compared with that measured by pumping tests, and the Nash-Sutcliffe efficiency coefficient is 0.96. The superior accuracy of the results obtained using the proposed method was confirmed by comparison with the results obtained using two established methods. The 2-D hydraulic conductivity distribution of the fault zone is potential for accurate and low-cost descriptions of groundwater and pollutant transport in the fault zone with strong heterogeneity.

Ecological vulnerability assessment of wetlands is a very important early-stage task for wetland protection, pollution treatment, ecological restoration and water resources utilization. On the basis of the study of vulnerability evolution mechanism of wetland ecosystem in the Yellow River Delta, this paper proposes a Pressure-Support-State-Response Model (PSSR) for ecosystem vulnerability assessment and employs a single-factor evaluation method. The proposed model is applied to assessing ecosystem vulnerability of wetland in Yellow River Delta (a case study of Dongying City). Research results show that: from 2005 to 2009, the ecosystem vulnerability of wetlands in Yellow River Delta was 0.62, and 0.68 from 2010 to 2014; the ecosystem vulnerability grade is moderately vulnerable during the two periods. Generally speaking, regional ecosystem vulnerability slightly decreases. More efforts should be made to protect and restore the ecosystem and prevent it from deterioration and wetlands degradation. This study may provide a theoretical support for wetland protection, management, exploitation and policy making in the Yellow River Delta.

In sportswear industry, the usage of synthetic material is increasing due to its excellent water transport characteristic. This study aims to evaluate the thermo-physiological comfort properties of different sports fabrics and to investigate the effect of fabric physical property and knitting parameter on comfort-related properties of commercial sportswear fabric. Vertical wicking test, wettability test, dry rate test as well as air resistance test were conducted on 17 types of polyester-knitted fabrics obtained from market. Analysis of variance and multiple-comparison least significant difference test was performed to select the best fabric for sportswear. A single jersey fabric sample No. 16 made of 75D/100f in 145 g/m2 as determined to be the best fabric for sports T-shirt due to its excellent wicking property, faster water absorbency, quicker dry rate, and lower air resistance. It is likely that finer filament, low fabric mass, and proper density are associated with best property. Besides, it ...

Last century 50 - 70 years, the dam construction of Shiyang Inland River Basin (SIRB) profound impact on the distribution of water resources and arable land in the basin. Through data collection, field surveys and remote sensing image interpretation, we analysis the use of land and water resources change process in the middle and lower reaches of SIRB in recent decades. The results show: (1) The cultivated area of SIRB has been an upward trend in recent decades, The whole basin cultivated area has increased total 229,000 hm2 from 1973 to 2010 and mainly in the middle and lower reaches. Midstream increased by 149,700 hm2 accounting for 65.36 percent of total, downstream increased by 70,000 hm2 accounting for 30.70 percent of total. (2) The amount of surface water resources of downstream reduce significantly gradually since dam construction, and the water table sharp decline. While the volume of surface water resources come downstream from the 1950s accounted for 30 to 40 percent of the total gradually reduced to less than 10% in 2012; (3) since the arable land area of middle and lower reaches of SIRB basin substantial increase, so the surface water resource does not meet irrigation needs. Agricultural irrigation relies heavily on exploitation of groundwater to supplement, resulting in Regional Groundwater Depth dropped rapidly, and forming several huge funnel groundwater settlements. 20 years from 1981 to 2001 the groundwater level of midstream dropped from around 5m to around 10m in Wuwei, and in Minqin dam-region of downstream along faster rate of decline in 20 years fell from 8.52 m to 22.68 m. Dam construction project has changed the pattern of the basin water cycle, the middle reaches closure a large number of surface water resources led to downstream sharp decline. Downstream continued exploitation of groundwater formed a few huge funnel groundwater settlements, it caused serious ecological problems. The basin should adjust the industrial structure and develop water saving irrigation, promote a virtuous cycle of water resources, to achieve sustainable development, seek a sustainable development ways conversion natural oasis to artificial oasis efficiency in arid zone.