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This paper presents an evaluation of the bearing capacity of cross-bracing in steel transmission tower structures. Design guidelines (ASCE 10-15, BS EN 50341-1, GB 50017-2017, and DL/T 5486-2020) related to the buckling capacity of the cross-bracing are summarized and compared with the experimental results. The current design provisions obtained the bearing capacity from the equivalent slenderness ratio, and then the stability coefficient and buckling capacity were derived. The calculated bearing capacity based on the design code tends to be overly progressive for smaller slenderness ratios (particularly those below 100), except for EN 50341-1-2012. Conversely, for larger slenderness ratios, ASCE 10-15 and DL/T 5486-2020 Class A design codes lean towards being overly progressive, while GB 50017-2017 and EN 50341-1-2012 codes tend to be more conservative. The design standard appears to exhibit unsafe predictions for Class A and B connections with low slenderness ratios and Class C connections. It needs to be noted that the effects of torsional stiffness and joint connection type are not considered in the current design codes, which are proved to be nonnegligible by the test results. In this paper, the bearing capacity calculation formula is proposed by introducing a modified effective length coefficient (K), and both the torsional stiffness and joint connection type are taken into account. The modified bearing capacity is verified with the test results; the correlation coefficient is 0.997, and the coefficient of variation is 0.04. It can provide a reference for the engineering design of steel lattice transmission tower structures. [ABSTRACT FROM AUTHOR]

An effective strategy to optimize the gas separation performance of hyperbranched polyimide (hyper‐PI) membranes by tuning their average cavity sizes is reported. Triphenylamine (TAPA) and 4,4′‐(Hexafluoroisopropylidene) diphthalic anhydride (6FDA) were used to prepare the hyper‐PI membrane, and the transformation in free fraction volume (FFV) was realized by the addition of an extra B2‐type monomer, 2,4,6‐Trimethylbenzene‐1,3‐diamine (DAM). In hyperbranched networks, DAM, in conjunction with 6FDA, generates longer linear parts and reduces the density of dendritic architectures formed by TAPA. The conformational freedom of hyperbranched TAPA‐6FDA is restricted, and chain packing is hindered. The ratio of DAM:TAPA predominantly influences both the average cavity sizes and the FFVs of the membranes, leading to the variation in gas permeabilities. DAM5:TAPA1‐6FDA shows the best performance in both O2/N2 and CO2/N2 separations. [ABSTRACT FROM AUTHOR]

The goal of cross-view image based geo-localization is to determine the location of a given street-view image by matching it with a collection of geo-tagged aerial images, which has important applications in the fields of remote sensing information utilization and augmented reality. Most current cross-view image based geo-localization methods focus on the image content and ignore the relations between feature nodes, resulting in insufficient mining of effective information. To address this problem, this study proposes feature relation guided cross-view image based geo-localization. This method first processes aerial remote sensing images using a polar transform to achieve the geometric coarse alignment of ground-to-aerial images, and then realizes local contextual feature concern and global feature correlation modeling of the images through the feature relation guided attention generation module designed in this study. Specifically, the module includes two branches of deformable convolution based multiscale contextual feature extraction and global spatial relations mining, which effectively capture global structural information between feature nodes at different locations while correlating contextual features and guiding global feature attention generation. Finally, a novel feature aggregation module, MixVPR, is introduced to aggregate global feature descriptors to accomplish image matching and localization. After experimental validation, the cross-view image based geo-localization algorithm proposed in this study yields results of 92.08%, 97.70%, and 98.66% for the top 1, top 5, and top 10 metrics, respectively, in CVUSA, a popular public cross-view dataset, and exhibits superior performance compared to algorithms of the same type. [ABSTRACT FROM AUTHOR]

Highlights: Highly efficient CuEDTA removal by an electrolyzer with MoS2 nanosheet cathode. Higher removal rate and Faraday efficiency compared with other widely reported electrocatalytic technologies. CuEDTA/Zn primary battery is constructed for the first time to realize CuEDTA removal and synchronous power generation. Electrocatalytic reduction of ethylenediamine tetraacetic acid copper (CuEDTA), a typical refractory heavy metal complexation pollutant, is an environmental benign method that operates at mild condition. Unfortunately, the selective reduction of CuEDTA is still a big challenge in cathodic process. In this work, we report a MoS2 nanosheet/graphite felt (GF) cathode, which achieves an average Faraday efficiency of 29.6% and specific removal rate (SRR) of 0.042 mol/cm2/h for CuEDTA at − 0.65 V vs SCE (saturated calomel electrode), both of which are much higher than those of the commonly reported electrooxidation technology-based removal systems. Moreover, a proof-of-concept CuEDTA/Zn battery with Zn anode and MoS2/GF cathode is demonstrated, which has bifunctions of simultaneous CuEDTA removal and energy output. This is one of the pioneer studies on the electrocatalytic reduction of heavy metal complex and CuEDTA/Zn battery, which brings new insights in developing efficient electrocatalytic reduction system for pollution control and energy output. [ABSTRACT FROM AUTHOR]

Triamine-based HBPI membranes are known for high gas separation selectivity and physical stability, but their permeabilities are still very low. In this study, we utilized a tetramine monomer called TPDA (N,N,N′,N′-tetrakis(4-aminophenyl)-1,4-benzenediamine) as a crosslinking center and incorporated an additional diamine comonomer called DAM (2,4,6-trimethyl-1,3-diaminobenzene) to enhance gas separation performance, especially gas permeability. The findings demonstrated that the resultant 6FDA−DAM/TPDA membranes based on tetramine TPDA exhibited a greater amount of free volume compared to the triamine-based HBPI membranes, resulting in significantly higher gas permeabilities. Furthermore, the higher concentration of DAM component led to the generation of more fractional free volumes (FFV). Consequently, the gas permeabilities of the 6FDA−DAM/TPDA membranes increased with an increase in DAM content, with a minimal compromise on selectivity. The enhanced gas permeabilities of the 6FDA−DAM/TPDA membranes enabled them to minimize the footprint required for membrane installations in real-world applications. Moreover, the 6FDA−DAM/TPDA membranes exhibited remarkable durability against physical aging and plasticization, thanks to the incorporation of a hyperbranched network structure. [ABSTRACT FROM AUTHOR]

Benign prostatic hyperplasia and its associated lower urinary tract symptoms seriously affect both the physical and mental health of older men. In order to determine the efficiency of Chinese Qigong Yi Jin Jing on prostate health in older individuals, thirty participants were randomized into either an Yi Jin Jing group (n = 15) or a control group (n = 15). After the 6-month intervention, the Yi Jin Jing group showed a significant decrease in international prostate symptom score and a significant increase in maximal urinary flow rate (compared with the control group p =.005, p =.001, respectively). Also, testosterone level increased and estrogen/testosterone ratio decreased in the Yi Jin Jing group (compared with the baseline p =.004, p =.002, respectively); estrogen level and estrogen/testosterone ratio were lower in the Yi Jin Jing group (compared with the control group p =.029, p =.012, respectively). The results showed that Yi Jin Jing is a promising way to reduce the risk of benign prostatic hyperplasia-lower urinary tract symptoms in older men. [ABSTRACT FROM AUTHOR]