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Significant damage has occurred to Ukraine’s water management infrastructure since the start of military operations in February 2022. This has led to the loss of key ecosystem services provided by reservoirs, including water supply, irrigation, and fishing. The total water resource loss is estimated to be about 18–20 km3, which is roughly a third of the country’s accumulated reserves. The economic and ecological efficiency of growing various crops on irrigated lands has been evaluated. The impact on industrial and recreational fishing, along with the loss of aquatic biological resources due to the drainage of littoral areas and spawning grounds, has also been assessed. Alternative water supply solutions for the regions affected by the conflict have been proposed and substantiated. Finally, strategies for the post-war development of Ukraine’s water sector, aimed at achieving both ecological and economic benefits, have been considered. [ABSTRACT FROM AUTHOR]

Translation abstract Bridge rehabilitation by means of UHPC overlays in AustriaThe rehabilitation and integralisation of the Steinbach Bridge on the motorway network between Vienna and Graz is Austria's first project using the method of strengthening by an UHPC overlay. As unique features, the bridge was neither sealed nor equipped with an additional wearing surface. Thus, the 7 cm thick, structurally effective UHPC layer works as water barrier and as carriageway surface. Experience from this pilot project has been incorporated into the UHPC guideline of the Austrian society for Construction Technology, both in terms of construction and design. In this article, the relevant key topics such as bond strength between UHPC and existing concrete, both statically and in terms of fatigue, crack widths, construction joints and surface grip are treated in more detail. The behaviour as well as the performance is presented by means of experiments. Design rules derived from those experiments are shown using the project Steinbach Bridge as an example. A closer look at the condition of the Steinbach Bridge after more than ten years of intensive use completes the picture of this still young but already well‐developed method of construction, which is now regulated by the guideline. [ABSTRACT FROM AUTHOR]

The membrane electrode assembly (MEA) is promising for practical applications of the electrocatalytic CO2 reduction reaction (CO2RR) to multi-carbon (C2+) compounds. Water management is crucial in the MEA electrolyser without catholyte, but few studies have clarified whether the co-feeding water in cathode can enhance C2+ formation. Here, we report our discovery of pivotal roles of a suitable nanocomposite electrocatalyst with abundant Cu2O−Cu0 interfaces in accomplishing water-promoting effect on C2+ formation, achieving a current density of 1.0 A cm−2 and a 19% single-pass C2+ yield at 80% C2+ Faradaic efficiency in MEA. The operando characterizations confirm the co-existence of Cu+ with Cu0 during CO2RR at ampere-level current densities. Our studies reveal that Cu+ works for water activation and aids C‒C coupling by enhancing formations of adsorbed CO and CHO species. This work offers a strategy to boost CO2RR to C2+ compounds in industrial-relevant MEA by combining water management and electrocatalyst design. Water plays a key role in electrocatalytic CO2 reduction, but the role of catalyst in water management is unknown. Here, the authors report the importance of catalyst in determining the function of water and demonstrate that the catalyst containing Cu+ promotes water activation and C2+ formation. [ABSTRACT FROM AUTHOR]

To address the challenge of precise flow rate measurement in microchannels, this research details the conceptualization and comprehensive evaluation of a thermal flowmeter which works on the principle of calorimetry for measuring small flow rates between 0.1 and 180 mL/h. The thermal flowmeter is composed of a silicone pipe, a heater, three platinum thermal sensors (T1, T2, T3), and water as the working fluid. The flowmeter is strategically placed to monitor the complex thermodynamics between upstream and downstream flows. The analysis revealed a notable decay in the slope of the temperature differences beyond a flow rate of 40 mL/h, indicating the exceptional sensitivity of the device at lower flow rates and making it an ideal choice for medical applications. Parametric analysis was also carried out to place the sensors at optimized locations for better sensitivity. [ABSTRACT FROM AUTHOR]

Municipal waterworks services in Surabaya City are considered inadequate and have caused many public complaints. To change this situation, innovation in government services is needed. The innovation provided must be in accordance with customer conditions and complaints. Municipal waterworks, which are regionally owned enterprises, are closely related to local governments; that is why governance innovation is needed. This study aims to describe innovative governance in Municipal Waterworks Surya Sembada Kota Surabaya. This study used the qualitative descriptive method. The subjects of this study were 5 Surabaya City people who were users of Municipal Waterworks Surya Sembada Surabaya services and 3 employees of Municipal Waterworks Surya Sembada Surabaya. The object of this study is the quality of services. Data collection techniques included interviews and documentation that is analyzed descriptively. Interviews were conducted about efficiency, effectiveness, conflict, orientation, and decision-making in providing services. The results obtained from this study show that Municipal Waterworks Surya Sembada Surabaya City has carried out innovative governance consisting of digitalization of services and work systems. Municipal Waterworks Surya Sembada Surabaya City uses the CIS (Customer Information System) application to make it easier for customers to report, pay, and register new installations. Innovative governance of Municipal Waterworks Surya Sembada Surabaya City has met eight indicators, namely, increased efficiency, improved effectiveness, improved service quality, no research conflicts, public interest orientation, carried out openly, fulfilled decision values, and accounted for the results. The human resources of Municipal Waterworks Surya Sembada Surabaya City are very competent but still experience obstacles in building communication with the community. The facilities and infrastructure of Municipal Waterworks Surya Sembada Surabaya City have met the standards, but additional transportation fleets are still required. Information technology of Municipal Waterworks Surya Sembada Surabaya City services has been maximized with the digitalization of services and work systems, but it is still constrained by applying for permits to local governments, which must be done manually and takes a long time. [ABSTRACT FROM AUTHOR]

Load‐carrying and deformation behaviour of penstock manifolds Steel penstocks of (pumped) storage power stations have penstock manifolds to distribute the works water from the main pipe to the individual branch pipes for the turbines and pumps in the power house. The paper sums up the results of a research project, lasting for two years, dealing with the load‐carrying and deformation behaviour of penstock manifolds, executed by the Institute of steel structures at Graz University of Technology. Based on nonlinear global analyses with 3D FE models with elastic and elastic‐plastic material models, the realistic behaviour of penstock manifolds was studied in detail. It was shown that such structures have an unexpected high plastic load‐carrying capacity. Based on that, higher settlements at the supports can no longer be assessed as that critical. A realistic assessment of the risk of fatigue with the structural stress concept also allows a focus on a few decisive areas in existing manifolds with regard to targeted inspection and monitoring measures. In addition, also the accuracy of the global analyses in the past was studied, using only a beam‐model in combination with 3D FE models for the individual bifurcations of the manifold, compared with a global 3D FE model of the whole manifold. [ABSTRACT FROM AUTHOR]

A large number of water mites of the species Kawamuracarus elongatus Uchida, 1937 were found to accumulate on a water-filtering sieve in a drinking water treatment plant in Fukuoka, Japan. Such a situation probably could be caused by the temporal reduction of the dissolved oxygen in the filtration bed. Newly recognized morphological features of this species are noted based on the specimens collected in Fukuoka. Further, water mites discovered so far in water supply systems in Japan are reviewed, and more accurate information of water mites as organisms of water supplies is provided.

The hydrogeological conditions of the Qianbei coalfield are complex, and karst water in the roof rock frequently disrupts mining operations, leading to frequent water inrush incidents. Taking the representative Longfeng Coal Mine as a case study, research was conducted on the development pattern of the water-conducting fracture zone and the water inrush mechanisms beneath karst aquifers. On the basis of key stratum theory and calculations of the stratum stretching rate, the karst aquifer in the Changxing Formation was identified as the primary key stratum. It was deduced that the water-conducting fracture zone would develop into the karst aquifer, indicating a risk of roof water inrush at the working face. Numerical simulations were used to study the stress field, displacement field, and plastic zone distribution patterns in the overlying roof strata. Combined with similar simulation tests and digital speckle experiments, the spatiotemporal evolution characteristics of the water-conducting fracture zone were investigated. During the coal mining process, the water-conducting fracture zone will exhibit a "step-type" development characteristic, with the fracture morphology evolving from vertical to horizontal. Near the goaf boundary, the strain gradually decreases, and the instability of the primary key stratum significantly impacts the mining space below, leading to the closure of interlayer voids or the redistribution of water-conducting fissure patterns. Field measurements of the water-conducting fracture zone reveal that postmining roof fractures can be classified into tensile-shear, throughgoing, and discrete types, with decreasing water-conducting capacity in that order, the measured development height of the water-conducting fracture zone (51 m) aligns closely with the theoretical height (51.37 m) and the numerical simulation height (49.17 m). Finally, from the perspective of key stratum instability, the disaster mechanisms of dynamic water inrush and hydrostatic pressure water inrush beneath the karst aquifers in the northern Guizhou coalfield were revealed. The findings provide valuable insights for water prevention and control efforts in the Qianbei coalfield mining area. [ABSTRACT FROM AUTHOR]

The conservation of 20th-century architectural heritage presents unique challenges due to the modern materials and construction techniques used by pioneering architects. This paper investigates the preservation challenges of iconic architectural works exposed to water environments, focusing on Fallingwater by Frank Lloyd Wright and the Boa Nova Tea House by Álvaro Siza Vieira. These structures, situated in natural settings with significant exposure to water, serve as case studies for examining conservation methods and their broader implications. This study explores archival documents, interviews with conservation experts, and literature reviews to highlight the main degradation phenomena related to the impact of environmental conditions on the material's integrity. Despite limited specific data on monitoring and maintenance, this research underscores the importance of ongoing conservation efforts. Fallingwater's case highlights the necessity of restoration techniques, while the Boa Nova Tea House illustrates minimal intervention strategies to maintain authenticity. This study concludes that the effective conservation of 20th-century built heritage necessitates a balance between preserving original design intents and adapting to environmental challenges. It emphasizes the need for innovative conservation strategies, adherence to international guidelines, and the establishment of comprehensive management and monitoring plans to safeguard the integrity and authenticity of culturally significant architecture. [ABSTRACT FROM AUTHOR]

The subject of investigation presented in this article is a filling and draining system of the ship lock installed in the Gabčíkovo Waterworks. This article describes the operation and construction of the special regulation segments, i.e., the check gates that are situated in the ship locks. After the failure and replacement of the original check gate with the new, improved one, the strain gauge sensors were applied to the new check gate in order to determine stress distribution on the segment surface as well as the loading of the actuating arms. The application method and application places of the strain gauge sensors are described in detail. The performed measurements detected the occurrence of additional motional resistances during the opening and closing of the check gate. These resistances caused a partial non-functionality of the original check gate actuating mechanism. [ABSTRACT FROM AUTHOR]

In order to ascertain the impact of working water flow rate and inlet pressure on the performance of the liquid–gas jet pump with square nozzle, the pumping volume ratio and efficiency of the liquid–gas jet pump with square nozzle were experimentally investigated at different inlet pressures and working water flow rates. Furthermore, the internal flow characteristics of the liquid–gas jet pump with square nozzle were explored through the utilization of visualization technology in the self-designed square-nozzle liquid–gas jet pump experimental setup. The findings indicate that the pumping ratio of the liquid–gas jet pump increases in conjunction with an elevation in the inlet pressure. Liquid–gas jet pump efficiency is higher at lower inlet pressures, up to 42.48%, and drops rapidly as inlet pressure increases. The pumping volume ratio of the liquid–gas jet pump increases significantly as the working water flow rate increases, and the working water flow rate exerts a minimal effect on the working efficiency of the liquid–gas jet pump. In the context of extreme vacuum conditions, a considerable number of droplets undergo substantial reflux in the posterior section of the throat, with a notable absence of bubbles in the diffusion tube. The size and number of bubbles diminish gradually along the axial direction. The objective of this paper is to provide a reference point for determining the optimal operational parameters for a square-nozzle liquid–gas jet pump in a practical context. [ABSTRACT FROM AUTHOR]

In order to minimize the subsequent cutting of aerospace structural parts of difficult-to-machine materials such as high-temperature alloys and to shorten the machining cycle, this paper proposes a machining method that uses electrical discharge machining (EDM) for initial hollowing. The method adopts a U-shaped fine copper tube electrode, with an open row of holes on this electrode in the processing area, and uses deionized water as a working medium to take advantage of the jet effect. The copper tube electrode in the processing area takes part in reciprocating movement to complete the EDM hollowing processing. Three types of feeds—linear feed, S-shaped feed, and lateral reciprocating feed—were designed for the copper tube electrodes. The material removal rate and tool wear ratio of the three feeds are compared and the etching mechanism is analyzed. It is found that the transverse reciprocating feed has the highest material removal rate, 29.99 mm3/min, which is 255% and 135% greater than those of the linear feed and S-shaped feed, respectively. The tool wear ratio of the transverse reciprocating feed is the lowest, at 3%, less by 60% and 46%, respectively, than for the linear feed and the S-shaped feed. The interpolar medium flow field formed by the lateral reciprocating feed is found to be more conducive to chip discharge. At the same time, the lateral reciprocating feed creates a mixed gas-liquid medium environment between the poles, which increases the breakdown voltage and increases the discharge gap. These results are favorable to the discharge of etched products, thus improving the material removal rate and the processing stability. [ABSTRACT FROM AUTHOR]

While controlling underwater adhesion is critical for designing biological adhesives and in improving the traction of tires, haptics, or adhesives for health monitoring devices, it is hindered by a lack of fundamental understanding of how the presence of trapped water impedes interfacial bonding. Here, by using well-characterized polycrystal diamond surfaces and soft, nonhysteretic, low-surface energy elastomers, we show a reduction in adhesion during approach and four times higher adhesion during retraction as compared to the thermodynamic work of adhesion. Our findings reveal how the loading phase of contact is governed by the entrapment of water by ultrasmall (10-nanometer-scale) surface features. In contrast, the same nanofeatures that reduce adhesion during approach serve to increase adhesion during separation. The explanation for this counterintuitive result lies in the incompressibility-inextensibility of trapped water and the work needed to deform the polymer around water pockets. Unlike the well-known viscoelastic contribution to adhesion, this science unlocks strategies for tailoring surface topography to enhance underwater adhesion. [ABSTRACT FROM AUTHOR]

Mesophase micro lotion is a special stable dispersion system, whose components mainly include surfactant, water and oil. This microemulsion system has a unique three-phase coexistence characteristic, that is, it can exist with the remaining water phase and the remaining oil phase at the same time, forming a complex phase structure, which has potential application value for the removal and treatment of pollutants. In order to further guide the preparation and optimization of micro lotion in industrial production and provide guidance for the design and development of new and efficient surfactants, a method for the formation of mid phase micro lotion and the determination of its characteristic parameters was proposed. The reservoir water solution, solid sodium carbonate, surfactant, polymer alkaline water solution and distilled water were prepared into five basic water samples and four working water samples in a certain proportion, and six alkyl aryl phosphates with different structures were prepared. The characteristic parameters of mesophase micro lotion under the influence of different alkyl chain lengths, different aromatic ring positions and different temperatures were measured. It can be seen from the experimental analysis that there are two particle size dispersion groups in the working water sample, namely, the nanometer sized mesophase micro lotion liquid bead and the nanometer sized fine mesophase micro emulsion liquid bead. When no alkali is added or the concentration of alkali is low, the working water sample contacts the crude oil to form the mesophase micro lotion； When the water sample time is from 7 d to 91 d, the accumulated liquid droplets of mesophase micro lotion formed by crude oil and working water sample U0D3 are reduced from 97% to 87%, which proves that there is instability in the mesophase micro lotion, and the salt resistance of the mesophase micro lotion is negatively related to the alkyl chain length and the aryl position, and positively related to the temperature change； The solubilization ability is positively correlated with alkyl chain length and aryl position, and negatively correlated with temperature changes [ABSTRACT FROM AUTHOR]

Adsorption chiller dynamics and its effect on the performance are greatly influenced by the adsorbent particle size because they govern both the micro (intra-particle) and macro (inter-particle) heat and mass transfer resistances within the adsorber bed. The net effect of adsorbent particle size and shape on the overall cooling system performance is addressed here. Initial CFD analysis of columnar adsorber bed with silica gel + water as the working pair, assuming uniform spherical adsorbent, showed increased uptake capacity with smaller sized (0.23 mm radius) particles over bigger sized (0.8 mm radius) ones despite smaller vapor penetration depth of the former. Subsequently, the effect of adsorbent particle size and shape on the overall cooling system performance is investigated experimentally in a single-stage one-bed mode for RD 2060 (0.8 mm radius) and RD 3070 (0.23 mm radius) silica gel specimens. Though the smaller size of RD 3070 is favourable for the adsorption kinetics at the particle level, its non-spherical shape and highly non-uniform size distribution resulted in significantly lower permeability and thermal diffusivity of the packed adsorber bed, thus hindering the cyclic steady state throughput. For the same operating conditions, RD 2060 and RD 3070 yield a cooling capacity (CC) of 107 W and 22 W, respectively. Further, the coefficient of performance (COP) drops by 73% in the case of RD 3070. The present study indicates that the adsorber bed design must consider both the adsorbent size and shape, in addition to other system operational parameters to enhance performance indicators. [ABSTRACT FROM AUTHOR]

Aircraft encounters with volcanic ash have caused significant damage over the past 40 years, resulting in particular attention being given to the issue. We analyzed the volcanic ash-aircraft encounter database published by the USGS. We added new volcanic eruptions and parameters such as eruption types, and dry–wet. Then, we applied standard and advanced statistical methods. Over 130 encounters have been documented in the mentioned database, with volcanic ash causing severe abrasions to the windshield, airframe, wings, and engine components. In nine cases, aircraft engines failed. We applied the binary regression analysis and some laboratory melting experiments on volcanic ash. Besides phreatomagmatism, we use the term external water in this work to describe meteoric water that enters volcanic plumes through precipitation or melting ice on ice-capped volcanoes. We demonstrated that engine failure occurs when our regression analyses undergo dry-to-wet conditions. In other words, statistically, there is a positive correlation between wet ash encounters with aircraft and engine failure incidents. Moreover, experiments conducted at 900 °C and under 40 bar pressure showed increased sintering in the dry sample, while melting textures were more prevalent in hydrated samples. We concluded that despite the various eruptive dynamics of volcanic ash, the introduction of external water into the volcanic plumes, probably causing instantaneous hydration of volcanic ash, is a common factor in engine failure incidents. Thus, we have identified the reasons behind engine failures during encounters between aircraft and volcanic ash and the specific damage that can occur depending on the type of eruption involved. [ABSTRACT FROM AUTHOR]

Crisis is a recurrent motif in discussions of the environment in the Middle East. Concerns about water scarcity, food insecurity, climate disasters, and resource degradation play into common associations of the region with conflict, malfunction, and despair. Yet this single story obscures as much as it illuminates. In this paper, I draw examples from my work on Nile water politics, climate change, and bread in Egypt to illustrate the power of this dominant narrative and its limitations. I reflect on the multiple stories that emerge when we shift our starting point or scale of analysis. I argue for the need to move beyond thinking about the environment just as a problem space to consider it as the space in which people are living their daily lives. [ABSTRACT FROM AUTHOR]

Many dammed reservoirs in dry climate conditions witness high sediment inflow rates due to higher soil erodibility, yet there are limited actual sediment influx measurements. Therefore, this study first applies the Soil and Water Assessment Tool (SWAT) hydrologic model to simulate reservoir sedimentation inflow to the Haditha Reservoir. Next, utilizing sediment inflows estimated by the SWAT model, the Trap Efficiency Function (TEF) is employed to estimate its remaining storage capacity and its useful life at multiple reservoir water levels. Calibration (1986–1997) and validation (1998–2007) of the SWAT model were conducted at three streamflow gaging stations and one sediment station located upstream of the reservoir. Results show that the SWAT model performed better during calibration than during the validation period for all streamflow and sediment gaging stations. In addition, modeled streamflow and sediment predictions were relatively more accurate on a monthly scale than on a daily scale. Simulated daily sediment inflow to the reservoir demonstrates slightly lower accuracy than daily streamflow, where the Coefficient of Determination (R2) and Nash-Sutcliffe Efficiency values are 0.34 and 0.32 in the case of sediment load, compared to 0.39 and 0.33 for streamflow, respectively. Reservoir storage capacity for the period (1986–2005) shows a continuous decrease with time at all reservoir water levels, which indicates an increase in sediment accumulation. According to measurements taken between 1986 and 2005, sediment accumulation has reduced the reservoir's capacity by approximately 15% at a water level of 112 m (the lowest water level in the reservoir). During the same period, the storage capacity loss at 147 m (the design working water level in the reservoir) was calculated to be 35%. Over 19 years of operation (1986–2005) at the 147-m water level, the total sediment buildup in the reservoir is estimated at 3.2 million tons. Notably, about one-third of this sediment was deposited in the five-year span from 2000 to 2005. [ABSTRACT FROM AUTHOR]

The present work examined water bath (WB) heating with microwave heating (WM) under different levels of transglutaminase (TGase) additions in a low-salt Mandarin fish surimi to obtain excellent gel properties. The breaking force was gradually enhanced with increased TGase additions (0.0 - 0.8 U/g), while WM with 0.8 U/g TGase produced the maximum gel strength. In the texture analysis, WM depicted a reduced hardness and an increased springiness at the corresponding TGase additions than that of WB. In low-field nuclear magnetic resonance spectroscopy (LF-NMR) studies, TGase reduced water protons’ relaxation times to different extents, while WM increased their water-binding abilities, especially at 0.8 U/g. Fourier transform infrared spectroscopy (FT-IR) revealed that the relative contents of the secondary structures did not apparently change at 0.2 - 1.0 U/g. Therefore, using WM and adding 0.8 U/g TGase improved the gel quality of low-salt Mandarin fish surimi gel, providing a new strategy for preparing healthy surimi products. [ABSTRACT FROM AUTHOR]

In multi-seam coal mining, the water accumulation in the goaf of the upper coal seam will seriously threaten the safety of the lower coal-seam recovery. How to accurately determine the water charging source in the goaf and predict the amount of water accumulation in the goaf after a certain time interval has become a major challenge that urgently needs to be solved in coal production. In this study, we consider the water-discharging goaf of the Tangjiahui Coal Mine as the object of research to investigate the problem of water accumulation in the goaf during the fully mechanized caving mining of extra-thick seams of top coal. We used geochemical methods, water-accumulation space methods, and large-well methods to analyze the hydraulic connections between goaf water and other aquifers, predict the amount of water accumulation in the goaf, and explore the characteristics of water level changes over time. We then used the results to discuss the relationship between the elevation of the accumulated water and the time taken for it to fill the goaf. The results showed that there is a hydraulic connection between the water in the airspace and the goaf water (GW), roof water (RW), floor water (FW) and Ordovician limestone water (OW); the volume of water in the goaf of the working face after mining was 2,106,838.496 m3. The average rate of water accumulation was 65.407 m3/h, and the goaf was expected to have been filled in 32,211.208 h. The derived relationship between the water level and time was H 0 = − 10 − 12 t 3 + 10 − 7 t 2 − 0.0042 t + 814.61   (R 2 = 0.9837) . This study is of great significance for the sustainable development of the safety evaluation of water blocking coal pillars at the mine boundary. [ABSTRACT FROM AUTHOR]

Maintenance-Renewal Works (MRWs) are among the most complicated planning operations of water companies and usually involve a group of experts. However, experts are often hesitant in their decision making as they often need to rely on unreliable quantitative operational data, which prompts doubts about the effectiveness of their decisions. This problem can be addressed by using linguistic (qualitative) values instead of imprecise numerical data. Hence, this study develops a qualitative-risk-based model to plan the MRW of six Iranian networks comprising pipes with unreliable operational data. The study also investigates the effectiveness of group decisions on planning pipe MRW. The results indicate that planning with imprecise numerical operational data can be improved by using a qualitative-risk-based model. Additionally, it is found that group decisions do not significantly change the pipe priorities, although they have a decisive effect on determining the pipe maintenance-renewal strategies. Furthermore, increasing the number of criteria is found to lead to more accurate results within the developed model, although increasing the number of decision-makers has no decisive effect on the results. [ABSTRACT FROM AUTHOR]

Aided by the local fractional derivative, we present a new local fractional (3+1)-dimensional Kadomstev-Petviashvili equation for describing the fractal water wave in this work. The non-differentiable transform is utilized to convert the local fractional equation into a local fractional ODE. On defining the Mittag-Leffler function on the Cantor sets, then a trialfunction based on the Mittag-Leffler function is proposed to seek for the non-differentiable exact solutions. The results reveal that the proposed method is a promising way to study the local fractional PDE arising in engineering and physics. [ABSTRACT FROM AUTHOR]

This work proposes a novel flat heat pipe technology, namely the rod-plate heat pipe, formed by the diffusion bonding of a set of parallel rods, of around 8 mm diameter, between flat plates of approximately 500 × 60 × 2 mm3. This design is inspired by the mini wire-plate heat pipe concept. This work is the first in the literature to apply this technology to large size heat pipes. A theoretical model is devised and used to predict the fluid distribution along the heat pipe, detect regions of flooding and dry-out and determine the best charging volume. Experiments are performed with a stainless-steel device operating in horizontal orientation with water as working fluid. Electrical cartridge resistances play the role of the evaporator heat source, while the condenser is cooled by either natural convection and radiation or heat exchangers linked to a thermal bath. For the experiments using a device with an exposed condenser, the minimum thermal resistance is 0.147 °C/W, for 88.50 W for heat input. The operation temperature increases with heat input up to 326.56 °C for a heat load of 191.40 W. The thermal resistances of the heat pipe cooled by heat exchangers have a minimum of 0.123 °C/W at 171.57 W heat transport rate, for a 40 °C thermal bath temperature. The theoretical results and data obtained so far corroborate the feasibility of this technology, with devices able to transfer up to 22.18 W per groove. [ABSTRACT FROM AUTHOR]

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This manuscript shows an innovative water-based processing route to fabricate lead-free piezoceramics. It faces the challenge of substituting conventionally used organic solvents by innocuous water. The procedure involves two methods of widespread use in industry: attrition ball-milling and freezing-lyophilization. Powders with nominal composition (Ba 0.92 Ca 0.08)(Ti 0.95 Zr 0.05)O 3 were effectively obtained. A narrow monomodal size distribution (600 nm) proved high reactivity that allowed solid-state synthesis at ultra-low temperature (700 °C-2 h). Optimal two-step sintering method (900 °C-3 h,1280 °C-6 h) allowed well-sintered homogeneous ceramics with pure tetragonal perovskite phase. They showed high piezo-sensitivity (d 33 =320 pC/N, d 31 =−110 pC/N, k p =31.45% and N p =2750 kHz·mm, ε ′ 33 T =3670, tanδ=0.036 at 1 kHz), comparable to that found for routes in organic media. Therefore, attrition ball milling in water and lyophilization work in synergy to successfully activate the precursors, influencing on the structural, microstructural and electrical properties of the final BCZT ceramics. This is an unprecedented development to produce piezoelectric ceramics using a sustainable, environmentally benign water-based process, with a positive impact in noteworthy industrial applications. • Novel mixed oxides route to fabricate (Ba 0.92 Ca 0.08) (Ti 0.95 Zr 0.05) O 3. • Attrition ball-milling in water, freezing and lyophilization activate the precursors. • Fine lyophilized powder (600 nm) allows ultra-low synthesis at 700 °C. • Two-step sintering at 1280 °C results in a pure tetragonal perovskite phase. • High piezo-sensitivity, alike that obtained by milling in organic media. [ABSTRACT FROM AUTHOR]

The essence of roof water inrush in coal mines fundamentally stems from the development of water-bearing fracture zones, facilitating the intrusion of overlying aquifers and thereby leading to water hazard incidents. Monitoring rock-fracturing conditions through the analysis of microseismic data can, to a certain extent, facilitate the prediction and early warning of water hazards. The water inflow volume stands as the most characteristic type of data in mine water inrush accidents. Hence, we investigated the feasibility of predicting water inrush events through anomalies in microseismic data from the perspective of water inflow volume variations. The data collected from the microseismic monitoring system at the 208 working face were utilized to compute localization information and source parameters. Based on the hydrogeological conditions of the working face, the energy screening range and its calculation grid characteristics were determined, followed by the generation of kernel density cloud maps at different depths. By observing these microseismic kernel density cloud maps, probabilities of roof water-conducting channel formation and potential locations were inferred. Subsequently, based on the positions of these roof water-conducting channels on the planar domain, the extension depth and expansion direction of the water-conducting channels were determined. Utilizing microseismic monitoring data, a quantitative assessment of water inrush risk was conducted, thereby establishing a linkage between microseismic data and water (inrush) data, which are two indirectly related datasets. The height of microseismic events was directly proportional to the trend of water inflow in the working face. In contrast, the occurrence of water inflow events and microseismic events exhibited a specific lag effect, with microseismic events occurring prior to water inrush events. Abnormalities in microseismic monitoring data partially reflect changes in water-conducting channel patterns. When connected with coal seam damage zones, water inrush hazards may occur. Therefore, abnormalities in microseismic monitoring data can be regarded as one of the precursor signals indicating potential floor water inrushes in coal seams. [ABSTRACT FROM AUTHOR]

Coal mine pre-grouting is an important means to reduce the risk of coal seam floor water inrush, and the scientific evaluation of its effects is an important basis for the formulation of water control countermeasures and the realization of safe mining. This paper takes the Guhanshan Mine 15,051 working face grouting project as the research object and selects the grouting volume, the length of the meter grouting, the dry material value in tons of water, the complexity of faults, and the threat of water inrush at the working face as the index factors with which to evaluate the effectiveness of the grouting. The geological structure is quantified by fractal theory. The subjective, objective, and comprehensive weights of the index factors are determined by the analytic hierarchy process, the CRITIC method, and the combination weighting method. The grouting effect on the working face is quantitatively identified by the fuzzy variable set comprehensive evaluation model, and zoning is carried out. The research shows that the areas with optimal, good, qualified, and poor grouting effect at the 15,051 working face account for 4.66%, 74.34%, 21.00%, and 0% of the working face area, respectively, and the proportion at the level of qualified or above accounts for 100%. The safety results at the 15,051 working face prove that the selected evaluation index factors are representative, the established model is reliable, and the evaluation results are in line with actual conditions. [ABSTRACT FROM AUTHOR]

Unmanned surface vehicles (USVs) are intelligent platforms for unmanned surface navigation based on artificial intelligence, motion control, environmental awareness, and other professional technologies. Obstacle avoidance is an important part of its autonomous navigation. Although the USV works in the water environment (e.g. monitoring and tracking, search and rescue scenarios), the dynamic and complex operating environment makes the traditional methods not suitable for solving the obstacle avoidance problem of the USV. In this paper, to address the issue of poor convergence of the Twin Delayed Deep Deterministic policy gradient (TD3) algorithm of Deep Reinforcement Learning (DRL) in an unstructured environment and wave current interference, random walk policy is proposed to deposit the pre-exploration policy of the algorithm into the experience pool to accelerate the convergence of the algorithm and thus achieve USV obstacle avoidance, which can achieve collision-free navigation from any start point to a given end point in a dynamic and complex environment without offline trajectory and track point generation. We design a pre-exploration policy for the environment and a virtual simulation environment for training and testing the algorithm and give the reward function and training method. The simulation results show that our proposed algorithm is more manageable to converge than the original algorithm and can perform better in complex environments in terms of obstacle avoidance behavior, reflecting the algorithm's feasibility and effectiveness. [ABSTRACT FROM AUTHOR]

Because of the long horizontal length and reservoir heterogeneity, water production and injection are different along different locations of a horizontal well. Besides, the conventional models for inferring interwell connectivity between directional wells are not suitable for horizontal wells. In this paper, a new model for inferring interwell connectivity between horizontal wells is built and a new water injection string is presented which can meet the demand of water injection of different locations for a horizontal well. Based on the conventional water injection string, a water distributor working cylinder was installed to respectively distribute water to root and toe of a horizontal well. A horizontal well can be considered as several directional wells with different physical properties such as permeability and porosity and so on. The reservoir is characterized as a coarse model consisting of a number of interwell units which is controlled by any two directional wells. Injection and production data were used to infer interwell connectivity and geological characteristics. The results obtained from the new proposed model are in consistent with the oxygen activation of injectors. Interwell connectivity coefficient of each injector was calculated and the preponderance flow paths were found. [ABSTRACT FROM AUTHOR]

The process of impinging-jet atomization involves the collision of multiple liquid jets to create atomization. This study specifically focuses on a system that utilizes impinging atomization with multiple jets. The injectors used in this study are arranged in either a planar configuration for doublet injectors or a stereoscopic configuration for quadruplet injectors, both designed to facilitate impinging atomization. The angle at which the jets collide is set at 90°, with injector intersection angles of either 60° or 120°. The diameter of the jets ranges from 0.8 to 1.1 mm, while the length–diameter ratio of the pipe remains fixed at 10. To investigate the atomization process, experiments were conducted by varying flow rates (ranging from 30 to 130 mL/min) from each injector using pure water as the working fluid. This resulted in a range of Weber numbers spanning from 4 to 206 and Reynolds numbers ranging from 578 to 3443. Four atomization regimes were observed in the impinging atomization flow field: closed-rim mode, periodic drop mode, open rim mode, and fully developed mode. The experiment utilized a high-speed camera to observe the formation and breakup of the liquid sheet. However, increasing the number of jets and altering the impingement configuration had minimal impact on the liquid sheet patterns as the Weber number increased. Compared to traditional double jet atomization, quadruplet jet atomization resulted in the wider extension of liquid sheets and similar atomization patterns. This study is useful for designing jet impingement-atomization systems for confined spaces. [ABSTRACT FROM AUTHOR]

Approximately 40 % of the final energy is used for heating and cooling of buildings. Of this, as much as 75 % is used in residential buildings. The proportion of energy needed in buildings is relatively high, so it is necessary to start using technologies that have low energy consumption, use it efficiently or provide it from renewable sources. One such technology is thermal energy storage, which allows us to store excess energy for later when we need extra energy. The paper presents two experiments in the field of adsorption space heating. In the first experiment, measurements were carried out on the adsorbents - zeolite 13X and zeolite NaYBFK, which were placed into a duct, through which humid air was transported by means of a centrifugal fan. In the second experiment, water vapour as the working medium was used. With the first experiment we achieved better water uptake on NaYBF, while the second experiment shows the increase of water uptake of zeolite 13X. [ABSTRACT FROM AUTHOR]

Self-compacting concrete, as a performing material whose casting and compacting can be made without applying the vibration technique, due to the flowability properties that allow it to flow by its own mass, was produced and tested in several versions of the material composition. Flowability gives high structural homogeneity and allows fast concrete pouring rate in a shorter time. During the experiment, four experimental versions were tested successively using coal ash, metallurgical slag, limestone dust as well as a combination of fly ash-slag as cementitious materials, that partially replaced Portland cement. Also, a water-reducing additive (polycarboxylate ether) was added in different ratios. Aggregates were chosen at low particle size (fine sand below 2 mm and granite gravel less than 12 mm). Mixing the materials together with the working water led to obtaining the paste with excellent flowability properties. The consolidated concrete had compactness and homogeneity and the mechanical characteristics were comparable to those of traditionally made concrete. Except for the remarkable flow characteristics of the paste, in this experiment it was proven that the compression strength of self-compacting concrete can reach very high values (after 28 days) of up to 60.4 MPa. [ABSTRACT FROM AUTHOR]

In newly commissioned drinking-water polyethylene (PE) pipes, biofilm develops on the inner pipe surface. The microbial community composition from colonization to the establishment of mature biofilms is less known, including the effect on the distributed water quality. Biofilm development was followed through 1.5 years in PE-pipe side streams at two locations of a full-scale, non-chlorinated drinking-water distribution system (leaving a waterworks versus 5–6 km from a waterworks) along with inlet and outlet water quality. Mature biofilms were established after ∼8–9 months, dominated by Proteobacteria, Actinobacteria and Saccharibacteria (61–93% relative abundance), with a higher diversity (OTUs/Shannon Index/16S rRNA gene amplicon sequencing) in pipes in the far end of the distribution system. Comamonadaceae, and specifically Aquabacterium (>30% of reads), dominated young (∼1.5-month-old) biofilms. Young biofilms were linked to increased microbiological counts in drinking water (HPC/ATP/qPCR), while the establishment of mature biofilms led to a drop in HPC and benefited the water quality, highlighting the importance of optimizing commissioning procedures for rapidly achieving mature and stable biofilms. [ABSTRACT FROM AUTHOR]

Graphene is a fundamental unit of carbon materials and, thus, primary sp2-bonded carbon material. Graphene is, however, easily broken macroscopically despite high mechanical strength, although its natural degradation has rarely been considered. In this work, we evaluate the natural degradation of two-layer graphene in vacuo, in low-humidity air, and in high-humidity air at 300, 400, 450, and 500 K. Over 1000 days of degradation at 300 K, the graphene structure was highly maintained in vacuo, whereas the layer number of graphene tended to decrease in high- and low-humidity air. Water was slightly reacted/chemisorbed on graphene to form surface oxygen groups at 300 K. At 450 and 500 K, graphene was moderately volatilized in vacuo and was obviously oxidized in high- and low-humidity air. Surprisingly, the oxidation of graphene was more suppressed in the high-humidity air than in the low-humidity air, indicating that water worked as an anti-oxidizer of graphene by preventing the chemisorption of oxygen on the graphene surface. [ABSTRACT FROM AUTHOR]

When the Brooklyn Waterworks opened in 1859, it was one of America's most advanced water and sewer systems. Yet after Brooklyn was annexed by New York City, the waterworks' history slipped into obscurity, despite having a now-famous champion: the "poet of America," Walt Whitman, whose brother worked on the project. This article shows the Brooklyn poet's fierce, multiyear lobbying effort for the waterworks in various newspapers and introduces a wealth of newly recovered Whitman writings on the issue. As a journalist, Whitman exemplifies the nineteenth-century press as an intermediary between expert engineers and popular readers. The poet brought precise expertise, translated engineers' technical arguments into everyday language for his readers, and fought the resulting day-to-day political battles over construction in print. Whitman, then, is an underappreciated case study of the confluence of technology, public health, and local journalism. [ABSTRACT FROM AUTHOR]

This study focuses on the economic value and carbon benefits of riparian buffers in urban drinking water production. The impact of riparian buffers on the waterworks operation in the Raccoon River watershed was quantified using the following metrics: nitrate concentration, days of nitrate removal operation, material and energy cost (based on 17 years of historical records with a watershed model), regression, and cost analysis. The findings indicate that the presence of riparian buffers in agricultural land can substantially decrease nitrate concentration in the water intake of the waterworks during the crop‐growing season: 19% in April, 9% in May, and 11% in June. These reductions mean less nitrate treatment of the plant intake flow: 23% in April, 12% in May, and 3% in June. These changes lead to significant resource savings: 425 metric tons of sodium chloride (NaCl), 147 810 kWh of electricity, 253 metric tons of powdered activated carbon, and 20.8 million liters of fresh water. The buffers would also reduce greenhouse gas emissions by 86.9 metric tons (CO2 equivalent) in 17 years. The total cost saving was estimated at $327 326, with the highest potential savings in May ($215 100), followed by April ($65 465), and June ($46 761). When factoring in buffer installation, cropland loss, nitrate removal, and cost associated with buffer harvest for biofuel in an established biomass market, the benefit to the entire watershed community would be $2.63 million annually. The results underscore the significant cost benefits and environmental benefits associated with cropland riparian buffers in a watershed community. The approach employed in this study holds promise for assessing riparian buffer benefits in other watersheds, contributes to an understanding of sustainable water management practices, and provides a basis for decision making in a wide range of agricultural regions. [ABSTRACT FROM AUTHOR]