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[Objective] The online real-time monitoring of water levels and flow rates in municipal sewage pipelines is crucial. It provides municipal workers with immediate insights into the operational conditions of these pipelines, enabling timely responses to any issues. However, current market offerings capable of simultaneous water level and flow rate detection are often prohibitive owing to their cost or complexity, limiting large-scale deployment. This highlights the need for an economically viable, real-time online device to monitor water levels and flow rates. In response to this need, we have designed a new device that measures both water levels and velocities using floating balls, all based on fluid flow theory. [Methods] In our study, we designed and manufactured a detection device based on flow field theory. The device measures water levels by tracking the distance between a fixed box and a hollow, stainless steel ball that floats on the water surface. A rod connects the ball and the measuring box, allowing us to determine water level changes by measuring the float ball's relative displacement. Flow velocity detection, alternatively, is indirect. We use a force sensor to measure the force exerted by the water flow on the floating ball. This force is transmitted and amplified by the lever mechanism of the rod. The flow velocity is then determined by sensing the thrust of the flow water on the floating ball. To prevent the floating ball from capturing debris, which could destabilize the flow and affect the measurements, we added a conical tail end to the floating ball, transforming it into a tail cone-tipped floating ball. The fish-like design of the floating device, featuring a large round head and a smaller cone tail, enhances its stability in water. The design of the measurement box encompasses hardware and software. The hardware of the detection system includes a microcontroller module, an A/D conversion module, and a display and remote data transmission module. The system receives water level and flow rate data through the device's GSM/GPRS module and transmits it to a remote monitoring endpoint, enabling remote online monitoring. We calibrated the water level and flow velocity measurement values of the detection device using experiments conducted on an open channel standard experimental platform. We then installed the device in an actual underground sewage pipeline for a 3-month on-site experimental monitoring of the sewage water level and flow velocity. [Results] The experimental results exhibit the following: 1 The improved floating device, equipped with a tail cone, is resilient to debris accumulation. This stability ensures the accuracy of the water level measurement process. 2 The deviation in measuring water level is within 3 mm, and the error does not exceed 0.5% of its full scale. The deviation value of flow rate measurement falls within ±0.04 m/s, and the error remains below 5% of its full scale. 3 Our onsite experimental monitoring results indicate that the detection device works normally. The monitored changes in water level and flow rate are consistent with the actual conditions, proving the measurements to be accurate enough for pipeline water flow condition monitoring. [Conclusions] The developed sewage pipeline water level and flow rate detection device offers several advantages. With its simple structure, low cost, and resistance to debris accumulation, it is an easy-to-install solution that can deliver remote data transmission. These issues make it well-suited for application across the entire sewage pipeline network. [ABSTRACT FROM AUTHOR]

Effective permeability is a key parameter for evaluating reservoirs and their productivity. With the wide application of resistivity logging tools in drilling, the advantages of resistivity logging in response to the dynamic invasion process of drilling fluids have become increasingly prominent. We analyzed the variation law of the measured resistivity data for different permeability formations at different times. In this study, we proposed an effective permeability modeling method based on the time-lapse resistivity logging data. First, based on the resistivity measurement data at different times, the dynamic resistivity profile of the reservoir was obtained through joint inversion; we then obtained the invasion depth and invasion zone resistivity of the drilling fluid at different times, along with the original formation resistivity. Subsequently, combined with parameters such as the soaking time, fluid viscosity, and saturation change of the drilling fluid, we obtained the phase permeability curve of the reservoir and dynamic effective permeability of the fluid near the wellbore. This study provides basic parameters for subsequent formation analyses and productivity prediction and substantially improves the reservoir evaluation technology from static to dynamic. [ABSTRACT FROM AUTHOR]

It has become clear that the anomalous properties of cuprate superconductors are intimately related to the formation of a pseudogap. Within the framework of the kinetic-energy-driven superconducting mechanism, the effect of the pseudogap on the electronic Raman response (ERR) of cuprate superconductors in the superconducting-state is studied by taking into account the interplay between the superconducting gap and pseudogap. It is shown that the low-energy spectra almost rise as the cube of energy in thechannel and linearly with energy in thechannel. It is also shown that the pseudogap is strongly anisotropic in momentum space, where the magnitude of the pseudogap around the nodes is smaller than that around the antinodes, which leads to that the low-energy spectral weight of thespectrum is suppressed heavily by the pseudogap, while the pseudogap has a more modest effect on the ERR in theorientation. [ABSTRACT FROM AUTHOR]

• HSP27 expression increased at both tissue and cellular levels after E. coli infection. • HSP27 overexpression enhanced the ability of IPEC-J2 to resist E. coli F18 infection. • RSK2 in the MAPK pathway may have a synergetic role with HSP27. Heat shock protein 27 (HSP27) plays an important role in protecting cells from various stress factors. This study aimed to investigate the function of HSP27 gene and its regulatory mechanism as infected by Escherichia coli (E. coli) at the tissue and cellular levels. Real-time PCR was used to detect the differential expression of HSP27 gene in F18 resistant and sensitive Sutai pigs and the differential expression upon E. coli F18ab, F18ac, K88ac bacterial supernatant, thallus infection and LPS induction in IPEC-J2. In addition, the HSP27 gene overexpression vector was constructed to detect the effect of the HSP27 gene overexpression on the adhesion of E. coli F18 to IPEC-J2, secretion of pro-inflammatory factors, and the expression of the upstream key genes in Mitogen-activated protein kinase (MAPK) pathway. Ribosomal S6 kinase (RSK2) is an important protein in the MAPK pathway. Therefore, the RSK2 gene overexpression vector was constructed and the number of colonies was counted after co-transfection of HSP27 and RSK2 gene. Results revealed that the expression level of HSP27 gene in resistant individuals in 11 tissues was higher than sensitive type. At the cellular level, the relative expression levels of HSP27 gene were increased after F18ab, F18ac bacterial supernatant, F18ab thallus infection, and LPS induction for 4 h (P < 0.01). The adhesion ability of E. coli F18ab to IPEC-J2 was significantly reduced after HSP27 gene overexpression (P < 0.01), and the concentration of pro-inflammatory factors in the HSP27 gene overexpression group was significantly reduced compared with the control group after F18ab infection (P < 0.05). Furthermore, the expression of RSK2 was significantly increased in HSP27 overexpression group upon F18ab infection (P < 0.01). The colonies quantitative results also showed that the number of colonies was significantly reduced after co-transfection of HSP27 and RSK2 gene. We indicated that the high expression of HSP27 gene may resist the inflammatory response caused by exogenous stress and enhance the ability of IPEC-J2 to resist E. coli F18 infection. RSK2 gene in the MAPK pathway may cooperate with HSP27 gene to participate in the immune response of the organism, which provides a theoretical basis for the study of the mechanism of anti- E. coli infection in piglets. [ABSTRACT FROM AUTHOR]

With the premise of investigating mechanical properties, the thermal conductivity of autoclaved aerated concrete (AAC) is a key index of self-insulation block walls for building energy conservation. This study focused on the effect of pore structures on the mechanical performance and thermal conductivity of AAC with the comparison of AAC base materials. Different kinds of AAC and their base materials were prepared and experimentally investigated. While maintaining a consistent mix proportion of the AAC base material, the pore structure of AAC was changed by the dosage of aluminum power/paste, foam stabilizer, and varying the stirring time of aluminum paste. The steam curing systems of AAC and the base material were determined based on SEM (Scanning Electronic Microscopy) and XRD (X-ray Diffraction) tests. With almost the same apparent density, the pore size decreased with the increasing content of foam stabilizer, and the mixing time of aluminum paste and foam stabilizer has a great influence on pore size. The thermal conductivity test and compressive test results indicated that that pore size had an effect on the thermal conductivity, but it had little effect on the compressive strength, and the thermal conductivity of sand aeration AAC was 8.3% higher than that of fly ash aeration AAC; the compressive strength was 10.4% higher, too. With almost the same apparent density, the regression mathematical model indicates that the thermal conductivity of AAC increased gradually with the increase of pore size, but it had little effect on the compressive strength. From the test results of basic mechanical properties, the mechanical model of cubic compressive strength, elastic modulus, axial compressive strength, and splitting tensile strength was obtained. The proposed stress–strain relationship model could well describe the relationship of AAC and the base material at the rising section of the curve. [ABSTRACT FROM AUTHOR]

• The pore diameter and pore number of AAC were obtained through the image. • The air pores of AAC were generated, and the AAC model was built by software. • The relationship between thermal conductivity/porosity and pore size was obtained. The pore structure has great influence on the mechanical properties and thermal conductivity of autoclaved aerated concrete(AAC). In this study, through the binary processing of the surface image of AAC, the pore diameter and number of AAC were obtained. Based on Monte Carlo method, the spherical coordinates of the air pores of AAC were generated by MATLAB software, and then they were imported into ANSYS software for modeling and grid generation. By comparing the pore size distribution and thermal conductivity between the finite element model and AAC product, to some extent, the finite element model in this paper is feasible. By the finite element analysis, the thermal conductivity is inversely proportional to the porosity and directly proportional to the pore diameter. Based on the thermal conductivity prediction model of porous materials, the mathematical models of porosity and thermal conductivity, pore diameter and thermal conductivity of AAC were established. [ABSTRACT FROM AUTHOR]

The triplet excited states of molecules play an important role in photophysical processes, which has attracted great research interest. Perylene diimide (PDI) is a widely studied material closely associated with the generation of triplet states, and it is highly anticipated to become an electron acceptor material for improving photovoltaic conversion efficiency. In this work, we prepared dimers and tetramers composed of selenium-modified PDI-C5 ( N,N '-bis(6-undecyl) perylene-3,4,9,10-bis(dicarboximide)) units. We investigated the photophysical processes of these dimers and tetramers in chloroform and toluene using UV-visible absorption spectroscopy, fluorescence spectroscopy, and femtosecond transient absorption spectroscopy. Both the dimers and tetramers undergo efficient triplet state formation processes in the solvents. Solvents with higher polarity facilitate charge transfer thereby promote the triplet states formation. The differences in the configurations of the dimer and tetramer molecules lead to variations in triplet states generation. The twisted angles in the tetramer restricted the intramolecular electronic coupling, posing certain hindrances to exciton coupling and lowering the intramolecular CT characteristics. The emission of excimer in tetramers also competes with the triplet states formation. The research demonstrates the influence of various factors on the generation of triplet states of PDI oligomers.

Fly ash is a potential alternative to activated carbon for mercury adsorption. The effects of physicochemical properties on the mercury adsorption performance of three fly ash samples were investigated. X-ray fluorescence spectroscopy, X-ray photoelectron spectroscopy, and other methods were used to characterize the samples. Results indicate that mercury adsorption on fly ash is primarily physisorption and chemisorption. High specific surface areas and small pore diameters are beneficial to efficient mercury removal. Incompletely burned carbon is also an important factor for the improvement of mercury removal efficiency, in particular. The C-M bond, which is formed by the reaction of C and Ti, Si and other elements, may improve mercury oxidation. The samples modified with CuBr2, CuCl2 and FeCl3 showed excellent performance for Hg removal, because the chlorine in metal chlorides acts as an oxidant that promotes the conversion of elemental mercury (Hg0) into its oxidized form (Hg2+). Cu2+ and Fe3+ can also promote Hg0 oxidation as catalysts. HCl and O2 promote the adsorption of Hg by modified fly ash, whereas SO2 inhibits the Hg adsorption because of competitive adsorption for active sites. Fly ash samples modified with CuBr2, CuCl2 and FeCl3 are therefore promising materials for controlling mercury emissions.