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Evaporative cooling is a widely employed method for air conditioning and heat dissipation, utilizing the phase transition of water to achieve simultaneous cooling and humidification. It relies on high-surface-area solid materials to enhance air-liquid contact upon wetting. However, these water-absorbing materials have drawbacks such as increased air resistance, degradation of water quality, and limited water retention capabilities. This study introduces a novel structure called the capillary container array (CCA) for effective humidification and cooling. The CCA structure overcomes the limitations of traditional methods by incorporating interconnected capillary containers with adjustable spacing and utilizing capillary forces to capture liquid droplets while minimizing the solid component. Compared to commercial paper-based wet curtains, the CCA structure offers significant advantages including strong water retention capabilities, high humidification performance, low air resistance and high pollution resistance. It increases water capacity by 6 times, humidification capacity by 8 %, and temperature drop by 2.2 °C. Moreover, it exhibits a 5-fold longer in water retention duration, a 30 % reduction in air pressure drop and a 3-fold increase in the performance coefficient, and maintains excellent water quality (<1 NTU) over prolonged operation. These advancements make the CCA structure highly promising for various applications in agriculture, industry and environmental conservation. • Application of CCA structures in humidification and cooling. • Capillary forces overcome gravity and create large gas-liquid surfaces. • The lower solids content reduces air resistance. • Maintain good circulating water quality. • Reduce pump energy consumption. [ABSTRACT FROM AUTHOR]

Considering the structural features of chrome-tanned collagen fibers (Cr-CF), the preparation of polymer modification fillers by using chrome shavings may be a feasible approach for the resource utilization of this tannery solid waste. Herein, Cr-CF from chrome shavings was used to modify the mechanical properties of melamine formaldehyde (MF) resin. Results proved that Cr-CF successfully toughened MF resin by intervening in the network polymerization and inhibiting the microcrack growth during material failure. The addition of 5 wt% Cr-CF powder that was prepared with an appropriate mechanochemical treatment enhanced the impact strength of MF resin by 324.4%, and increased the loss factor at 25 °C by 71.4%. These modification effects of Cr-CF were superior to those of other modification fillers. Therefore, the preparation of Cr-CF into toughening agent for thermosetting resin is a feasible method to achieve the effective recycling of chrome shavings. [Display omitted] • Using chrome-tanned collagen fibers as toughening fillers is a new method for the high-value utilization of chrome shavings. • Melamine formaldehyde resin was well toughened via blending with chrome-tanned collagen fibers. • Chrome-tanned collagen fibers intervened the network polymerization of melamine formaldehyde resin. • Chrome-tanned collagen fibers had the ability to inhibit the microcrack growth during material failure. • The toughening effects of chrome-tanned collagen fibers were superior to those of traditional fillers. [ABSTRACT FROM AUTHOR]

Abstract: DNA microarray provides a powerful basis for analysis of gene expression. Bayesian networks, which are based on directed acyclic graphs (DAGs) and can provide models of causal influence, have been investigated for gene regulatory networks. The difficulty with this technique is that learning the Bayesian network structure is an NP-hard problem, as the number of DAGs is superexponential in the number of genes, and an exhaustive search is intractable. In this paper, we propose an enhanced constraint-based approach for causal structure learning. We integrate with graphical Gaussian modeling and use its independence graph as an input of our constraint-based causal learning method. We also present graphical decomposition techniques to further improve the performance. Our enhanced method makes it feasible to explore causal interactions among genes interactively. We have tested our methodology using two microarray data sets. The results show that the technique is both effective and efficient in exploring causal structures from microarray data. [Copyright &y& Elsevier]

Collagen fiber network (CFN) is a kind of supermolecule composed of collagen molecules with a hierarchical structure. As collagen fibers possess this kind of structure and a relatively high nitrogen content, they have the potential to be processed into an efficacious flame-retardant filler. To realize this potential, the dispersion and fixation of collagen fibers must be controlled effectively. In this study, a series of CFNs with collagen fiber dispersed to different extents and those fixed with different tanning agents were prepared. The fiber dispersion, limiting oxygen index (LOI), combustion performance, thermal stability, carbon residue morphology, carbon residue composition, and thermal conductivity of these CFNs were characterized. The results showed that the flame retardancy of the CFNs improved with an increase in dispersion extent of collagen fibers and removal of the interfibrillar substance. The CFN fixed with 4 wt% zirconium tanning agent (based on ZrO 2) showed the best flame-retardant performance. Its LOI, total heat release, char yield at 800 °C and thermal conductivity were 62.3%, 15.51 MJ m−2, 18.33%, and 0.1362 W m−1 K−1, respectively. Because of these properties, this Zr-loaded CFN can be considered as a valuable flame retardant modifier for polymer materials. Image 1 • The novel flame retardance material based on collagen fiber network. • The strategy for control the structure and property of collagen fiber network. • A novel way to utilize collagen fiber material. [ABSTRACT FROM AUTHOR]

The feasibility of preparing refractory materials from ferrochromium slag was explored by assessing the influence of magnesia addition on the phase composition, microstructure and properties of refractory materials. The thermodynamic calculation results revealed that the presence of magnesia increased the amount of forsterite and spinel phases, and reduced liquid phase, which contributed significantly to improve the melting point of the ferrochromium slag system. The XRD and SEM-EDS analyses indicated that increasing the addition of magnesia was beneficial to the transformation and crystallization of the forsterite and spinel phases. In particular, as the magnesia addition changed from 0 wt % to 25 wt %, the growth of the spinel phase was significantly promoted, with the average spinel grain size increased rapidly from 2.42 μm to 11.36 μm. An excellent refractory material could be prepared by selecting an appropriate magnesia addition of 25 wt %. [ABSTRACT FROM AUTHOR]

Recently, carbon-based composite aerospace and mechanical structures have considerable attention due to their great material and mechanical properties. Carbon nanotubes (CNTs) or graphene platelets (GPLs) reinforcements for different matrices are common for the design of modern multilayer structures. In the present paper, the supersonic flutter of nanohybrid composite multilayer panels is examined and discussed. The nanohybrid multilayer panel is made of different technologically justified configurations of polymer layers reinforced by CNTs and GPLs The effective material properties of each CNTs and GPLs layer are determined according to two well-established homogenization techniques: the Mori–Tanaka scheme and the modified Halpin–Tsai model, respectively. Reddy's third-order shear deformation theory is applied to avoid determining shear correction factors for different distributions of material properties. Hamilton's principle and the first-order piston theory are applied to formulate aeroelastic coupled equations of motion of the panel. The numerical meshless method is employed to discretize dynamic equations and find generalized multi-parametric characteristic equations functionally dependent on the parameters of the structure with different boundary conditions. The accuracy of the obtained solution and results is examined by comparing the determined natural frequency and critical aerodynamic pressure with those obtained in previous studies. Then, a comprehensive parametric study is carried out to show the effects of hybridization of different distribution patterns of CNTs and GPLs, weight fractions, total layer number, and aspect ratio of hybrid composite panels on the flutter bounds. Results show that the present method provides a highly effective general numerical model for flutter analysis of hybrid nanocomposite panels with different boundary conditions for all thickness categories including thick plates. Moreover, an optimization nanoparticles distribution for the flutter of the nanohybrid composite panel has been obtained. • Flutter of novel polymer nanohybrid panel is investigated. • Epoxy/polymer matrix is assumed for each layer to reduce inter-laminar stresses. • Panels with FG-X pattern have the highest flutter bound. • Panels with FG-O pattern have the lowest flutter bound. • New insights into the nonlinear stability of nanohybrid panels. [ABSTRACT FROM AUTHOR]

Two tetra-nuclear cyanide-bridged square complexes [ cis -Fe(bpy) 2 (CN) 2 Mn( L )] 2 [PF 6 ] 4 ( 1 ) and [ cis -Os(bpy) 2 (CN) 2 Mn( L )] 2 [PF 6 ] 2 [ClO 4 ] 2 ( 2 ) (bpy = 2,2′-bipyridine, L = 1,6-diphenyl-2,5-bis(2-methylpyridyl)-2,5-diazahexane) were synthesized and fully characterized. The tetra-nuclear [ cis -M(bpy) 2 (CN) 2 Mn( L )] 2 4+ (M = Fe ( 1 ), Os ( 2 )) cation is composed of two [M(bpy) 2 (CN) 2 ] and two [Mn(L)] 2+ centers. Each M II ion adopts a distorted [MN 4 C 2 ] octahedral coordination, surrounded by four nitrogen atoms from two bpy ligands and two carbon atoms from the cyanide groups in a cis position. Each Mn 2+ ion adopts a distorted [MnN 6 ] octahedral coordination, occupied by four nitrogen atoms from L and two nitrogen atoms from the cyanide groups in a cis position. The magnetic susceptibilities measurements indicate 1 is weak ferromagnetic, and 2 is weak antiferromagnetic. [ABSTRACT FROM AUTHOR]

Twin-entry radial turbine has an evident advantage of enhancing the output power in internal combustion engine, while it is confronted by complex inlet conditions because of the interval flow feeding into two limbs. Although the performance of twin-entry turbine is notably influenced by admission conditions, detailed flow mechanism is yet fully revealed in previous researches. This paper investigates the mechanism of the influence by different admissions on a nozzleless twin-entry turbine via experimentally validated numerical methods. Turbine performance is studied under different admission conditions and the results demonstrate that twin-entry turbine performance is notably different between two partial admission conditions, although the volute passage is symmetrically divided. Rotor decomposition methods are employed for the analysis of loss distributions to understand this performance difference. Flow separation and tornado vortex generated near the rotor inlet is confirmed as the key source for the flow loss in the rotor. The off-design incidence angle near the hub rather than the shroud is the reason for the vortex initiation in the twin-entry turbine. Moreover, the volute flow features demonstrate that volute leakage flow is the reason for the lower incidence angle near the blocked limb. Consequently, the mechanism of the asymmetric performance of the symmetric twin-entry turbine under partial admission conditions is revealed. [ABSTRACT FROM AUTHOR]

Two tetra-nuclear cyanide-bridged molecular square complexes [M II (dppm) 2 (CN) 2 (Co II Cl 2 )] 2 (M = Ru, 1 ; M = Os, 2 ) (dppm = bis(diphenylphosphino) methane) were synthesized and characterized by elemental analysis, IR, electronic absorption spectra and single-crystal X-ray diffraction analysis. Both the isostructure complexes 1 and 2 crystallize in monoclinic space group P 21/ c , and possess two cis -M(dppm) 2 (CN) 2 (M = Ru, 1 ; M = Os, 2 ) and two CoCl 2 units through cyanido bridges. What’s more, the environment around the Co(II) atoms in 1 and 2 define a slightly distorted tetrahedron, and are coordinated by two nitrogen atoms from the cyanide groups with cis -configuration and by two chlorine atoms. Temperature dependence of magnetic susceptibilities show both 1 and 2 are weak antiferromagnetic coupling between the paramagnetic Co(II) ions across a diamagnetic cyanidometal –NC–M(II)–CN– bridge. Furthermore, complex 1 exhibits spin-canted behavior. However, there is no such magnetic behavior in complex 2 , which may result from the more diffuse nature of the 5d orbits with respect to 4d. [ABSTRACT FROM AUTHOR]

The large-amplitude free vibration behaviors of rotating pre-twisted functionally graded (FG) nanocomposite multilayered blade reinforced with graphene platelets (GPLs) in a thermal environment is comprehensively investigated in the paper. It is assumed that the GPLs volume fraction varies gradually from layer to layer across the blade thickness direction but remains constant in each individual GPLs-reinforced composite (GPLRC) layer. The modified Halpin-Tsai micromechanical model is exploited to obtain the effective Young's modulus of each GPLRC layer while Poisson's ratio, mass density, and thermal expansion coefficient are determined via Voigt's rule. The nonlinear dynamic model of pre-twisted GPLRC blades at moderate rotational speed in a thermal environment is derived based on the first-order shear deformation theory (FSDT) combined with the improved version of the Novozhilov nonlinear shell theory. The nonlinear vibration characteristics of FG GPLRC blades are obtained by applying the element-free improved moving least-square Ritz (IMLS-Ritz) method in conjunction with a direct iterative scheme. Validation of obtained results is performed in detail and show effectiveness of used numerical approach and fast convergence of obtained results to exact values. The impacts of rotating speed, pre-twisted angle, presetting angle, and aspect ratio on nonlinear to linear frequency ratio of GPLRC blades are studied with emphasis on temperature rise and nano reinforcement parameters. Finally, new insights into dynamics of nanocomposite rotating blades with conclusions are presented in detail. [ABSTRACT FROM AUTHOR]

This paper investigates turbine performance and gasdynamic behaviours of a radial turbine confronted by pulsating inflow via detailed flow measurement. Firstly, pressure propagation in the volute over circumferential direction is captured by six pressure transducers. The propagation speed is confirmed to be the sum of bulk flow velocity and sonic velocity by the experiment. Local flow parameters also propagate at the same speed with pressure pulse, which indicates that pulsations of the flow parameters are driven by the pulse of pressure. An evident phase-shift is observed between input power and output work, which is mainly resulted from the pulse propagation in the inlet duct. Furthermore, the pressure pulse at rotor inlet is evidently out-of-phase with that at rotor exit, producing a larger hysteresis loop of swallowing capacity. Specifically, the cycle-averaged input work is about 22.2% higher than the case with constant exit pressure. It is found to be resulted from the phase-flip of the pulse at rotor exit due to the gasdynamic behaviour at the interface between the rotor and exit duct, where sudden expansion happens. This paper unveils the gasdynamic behaviours of turbine confronted by pulsating inflow and can have a guide effect for performance enhancement design methodology. • Gasdynamic behaviours of turbine exposed to pulsating flow are experimentally and numerically studied. • Pressure, temperature and mass flow propagate at same speed of sonic speed puls flow velocity. • Phase shift between input/output power results from pulse propagation in inletduct and volute. • Pulse phase-flip in rotor leads to 23.4% wider range of pressure ratio and 22.2% higher power. • Pulse phase-flip at trailing edge resluts from gasdynamic behaviours of sudden expansion. [ABSTRACT FROM AUTHOR]

Twin-entry radial turbine has evident advantages on energy recovery of internal combustion engine because of better utilization of exhaust pulse energy. One-dimensional performance prediction plays an important role in automobile industry because of the cost-effective feature. However, as twin-entry turbine is confronted by out-of-phase pulses, to capture the flow distortion by twin-entry turbine model is challenging, especially under partial admission conditions. This paper establishes a reduced-order parallel-rotor model for performance prediction of twin-entry nozzleless radial turbine based on internal flow characteristics. Firstly, twin-entry turbine experiment and 3D simulation are applied to analyze the different flow features under partial admission conditions. The flow distortions in the spanwise and circumferential directions are both demonstrated. Based on these flow characteristics, a reduced-order twin-entry turbine model with parallel rotor passages is established for predicting the rotor at distorted flow field. Finally, the model is carefully validated against the results of CFD. The results show that satisfied consistency can be obtained and the maximum discrepancy of turbine performance is 3.8% and the performance difference and flow distortion under partial admissions can be captured, thus prove the credibility of the model. This investigation provides a reliable methodology for performance prediction and behavior analysis of twin-entry turbine. • A reduced order twin-entry turbine model is established based on flow characteristics. • Leakage flow makes incidence angle diverse at spanwise and circumference directions. • Twin-entry turbine rotor is divided into four parallel ones to simulate the flow distortions. • The 'parallel rotor' model is well validated and the maximum discrepancy is 3.8%. [ABSTRACT FROM AUTHOR]

Self-assembly of pyrazine-2-carboxylate (pyzca) with silver (I) nitrate in the aqueous-acetonitrile solutions results in a new coordination polymer, Ag(pyzca) (1). Crystal data: 1, orthorhombic, P21nb, a=6.954(2) Å, b=7.041(2) Å, c=11.527(2) Å, V=564.3(2) Å3, Z=4. The structure of 1 is constructed by a fascinating assembly of two kinds of helices along the a-axis ⧠ namely single helices [Ag&z.sbnd;O&z.sbnd;C&z.sbnd;C&z.sbnd;C&z.sbnd;N]n and triple helices [Ag&z.sbnd;O&z.sbnd;C&z.sbnd;C&z.sbnd;C&z.sbnd;N&z.sbnd;Ag&z.sbnd;N&z.sbnd;C&z.sbnd;C&z.sbnd;C&z.sbnd;N]n. The bonding interaction among the helical chains give 1 a silver three-connected three-dimensional framework structure in which the silver ions are coordinated by pyzca bridges. [Copyright &y& Elsevier]