Why a mosquito leg possesses superior load-bearing capacity on water:Experimentals

Mosquitoes possess the striking ability to walk on water because each of their legs has a huge water supporting force（WSF） that is 23 times their body weight.Aiming at a full understanding of the origins of this extremely large force,in this study,we concentrate on two aspects of it：the intrinsic properties of the leg surface and the active control of the initial stepping angle of the whole leg.Using a measurement system that we developed ourselves,the WSFs for the original leg samples are compared with those whose surface wax and microstructures have been removed and with those of a different stiffness.The results show that leg f exibility plays a dominant role over surface wax and microstructures on the leg surface in creating the supporting force.Moreover,we discuss the dependence relationship between the maximum WSF and the initial stepping angle,which indicates that the mosquito can regulate this angle to increase or decrease the WSF during landing or takeoff.These finding are helpful for uncovering the locomotion mechanism of aquatic insects and for providing inspiration for the design of microfluids miniature boats,biomimetic robots,and microsensors.

Roof pre-blasting to prevent support crushing and water inrush accidents

Support crushing and water inrush when mining under an unconsolidated confined aquifer in the Qidong Coal Mine was prevented by roof pre-blasting. The mechanism and applicable conditions for this method have been studied. The results show that when an overburden structure that may cause support crushing and a water inrush accident exists the weakening of the primary key stratum, which thereby reduces its weighting step, roof pre-blasting is both feasible and effective. If the position of the primary key stratum can be moved upward to exceed 10 times the mining height the possibility of support crushing and water inrush disaster caused by key stratum compound breakage will be lowered. The overburden structure of the number 7121 working face was considered during the design of a technical proposal involving roof pre-blasting. After comprehensively analyzing the applicability of roof pre-blasting the resulting design prevented support crushing and water inrush disasters from happening at the number 7121 working face and laid a solid foundation for mining safely.

Water environmental planning for new zone of economic-technological development in China

This paper analyzes the characteristics of water environmental planning in New Zone for EconomicTechnological Development (NZETD) in China and presents the task, procedure and method of the planning study Based on these analyses, the concept of Water Environmental Support Capacity (WESC) is put forward and the corresponding quantitative method is proposed to achieve the objective of coordinating the relationship between water environment and economic development As a case study, a comprehensive analysis and integrated water pollution control planning are made for the New Zone of EconomicTechnological Development in Benxi City in China Based on the costbenefit analysis and feasibility study of the planning alternatives, the comprehensive indexes of WESC are calculated and applied to evaluate the water pollution control planning alternatives

Water inrush evaluation of coal seam floor by integrating the water inrush coefficient and the information of water abundance

The method of singular coefficient of water inrush to achieve safety mining has limitation and one sidedness. Aiming at the problem above, large amounts of data about water inrush were collected. Then the data, including the maximum water inrush, water inrush coefficient and water abundance in aquifers of working face, were processed by the statistical analysis. The analysis results indicate that both water inrush coefficient and water abundance in aquifers should be taken into consideration when evaluating the danger of water inrush from coal seam floor. The prediction model of safe-mining evaluation grade was built by using the support vector machine, and the result shows that this model has high classification accuracy. A feasible classification system of water-inrush safety evaluation can be got by using the data visualization method which makes the implicit support vector machine models explicit.

Study on urban water environmental support capacity

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Placement of a Jejunal Feeding Tube via an Ultrasound-Guided Antral Progressive Water Injection Method

Background： Jejunal feeding tube allows the nutrition of critical care patients more easy and safe. However, its placement remains a challenge. This study aimed to introduce a jejunal feeding tube through an ultrasound-guided antral progressive water injection method and subsequently to examine its efficacy. Methods： Between April 2016 and April 2017, 54 patients hospitalized in the Department of Critical Care Medicine, Peking Union Medical College Hospital, China who needed nutritional support through a jejunal feeding tube were recruited for this study. Patients who applied ultrasound-guided antral progressive water injection method were classified into the experimental group. Patients who applied conventional method were registered as control group. Results： No significant differences were found in age, body mass index, and Acute Physiology and Chronic Health Evaluation score, but a significant difference in operation time was found between the experimental group and the control group. Of the 24 individuals in the control group, 17 displayed clear catheter sound shadows once the tube entered the esophagus. In comparison, of the 30 individuals in the experimental group, all harbored catheter sound shadows through the esophageal gas injection method. Subsequent observation revealed that in the control group （via ultrasonographic observation）, 15 individuals underwent successthl antral tube entry, for a success rate of 63%. In the experimental group （via antral progressive water injection）, 27 individuals underwent successful antral tube entry, for a success rate of 90%. There was a significant difference between the success rates of the two groups （x2 = 5.834, P= 0.022）. Conclusion： The antral progressive water injection method for the placement of a jejunal feeding tube is more effective than the traditional ultrasonic placement method.

Dynamic simulation of China’s water-grain-meat system and evaluation of its support capability based on water footprint theory

The supply capacity of water resources,food and meat products is of great importance to the people’s livelihood of a country.In recent years,although China has introduced many policies on water resources and grain production,the current situation of China’s food self-sufficiency and imbalance between supply and demand of water resources has not been fundamentally changed.Food security and water security are facing a serious situation.This paper takes the water footprint as the connection point,and combines the water food meat system with mutual influence,mutual causation and dynamic feedback into a composite system.At the same time,the simulation model of the composite system is established by using system dynamics,and the dynamic simulation of water grain meat in China from 2000 to 2050 is carried out to explore the current situation and future development trend of China’s water,grain and meat supply capacity.It was found that during the simulated period,the agricultural blue-green water footprint on the demand side would continue to dominate,followed by the gray water footprint.The blue water footprint on the supply side remained stable,whereas the green water footprint and the circulating water footprint showed an upward trend.According to the contemporary social and economic development and the model of water resources in China,there will be no meat shortage in the future,but issues have been found in the ability to guarantee water and food supply.The root of China’s food support capability problem is excessive grain consumption due to meat production,whereas the cause of the water support capability problem is the slow development of the water conservation.Food support capability issues can be solved by regulating the meat output of livestock farming and fishery operations,reducing excess production capacity,and stabilizing the meat supply and demand.To solve the water support capability issue,China should focus on accelerating the pace of agricultural water-conservation development,improving the sewage treatment system,building rainwater-collection projects,and promoting the research and development of water recycling technology.This study provides support for optimizing the structures of the meat and grain industries and the policy formulation of the efficient use of water resources in China.

Elimination of Surfactants and Small Dyes from Water with Silicasupported Dendritic Amphiphiles

Silica-supported branched polyethylenimine（Sil@PEI） is a conventional adsorbent and shows a limited affinity to anionic surfactants and small dyes（K = 106？107 L/mol）. If the PEI is alkylated with cetyl groups（C16）, the K of the resulting adsorbents（Sil@PEI@C16-x, where x is the fraction of PEI units being alkylated） is significantly improved. Optimization shows that Sil@PEI@C16-0.15 can best reduce aqueous surfactants to a residue around 10？10 mol/L; while Sil@PEI@C16-0.6 can reduce even small aqueous dyes to a residue below 10？10 mol/L, nearly 105-fold lower than that by Sil@PEI. The adsorbents are well recyclable. It is believed that in the case of dyes, the dense cetyl shell can isolate the PEI from the bulky water and thus suppress the competitive binding by water; while in the case of surfactants, the semiclosed cetyl shell can simultaneously meet electrostatic complement and hydrophobic complement to the surfactants.

Using Linked Data in a heterogeneous Sensor Web: challenges, experiments and lessons learned

Abundant sensor data are now available online from a wealth of sources,which greatly enhance research efforts on the Digital Earth.The combination of distributed sensor networks and expanding citizen-sensing capabilities provides a more synchronized image of earth’s social and physical landscapes.However,it remains difficult for researchers to use such heterogeneous Sensor Webs for scientific applications since data are published by following different standards and protocols and are in arbitrary formats.In this paper,we investigate the core challenges faced when consuming multiple sources for environmental applications using the Linked Data approach.We design and implement a system to achieve better data interoperability and integration by republishing real-world data into linked geo-sensor data.Our contributions include presenting:(1)best practices of re-using and matching the W3C Semantic Sensor Network(SSN)ontology and other popular ontologies for heterogeneous data modeling in the water resources application domain,(2)a newly developed spatial analysis tool for creating links,and(3)a set of RESTful OGC Sensor Observation Service(SOS)like Linked Data APIs.Our results show how a Linked Sensor Web can be built and used within the integrated water resource decision support application domain.