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• The strength of the TC4-CFRTP joint was improved by adding PA6/epoxy interlayer. • The addition of interlayer increases the binding area of TC4 and CFRTP. • The joining mechanism and fracture mechanism of the joint was revealed. • The temperature of the joint interface during welding was measured. Ti-6Al-4 V titanium alloy (TC4) and carbon fiber reinforced resin matrix composites (CFRTP) were successfully connected by laser welding after adding PA6 or epoxy as the interlayer. Experiments and simulations were performed to clarify the influence of the interlayers on the joint characteristics, including the strength, interfacial microstructure, failure behavior and joining mechanism under different laser heat inputs (LHI). The results showed that with the increasing heat inputs, the joint strength first increased and then decreased in accordance with the degree of melting/decomposition of the PA6/epoxy interlayer. When the interlayer was PA6, the highest tensile strength of 3428 N was generated under 38.5 J/mm. When the interlayer was epoxy, the highest tensile strength of 3855 N was generated under 45 J/mm. For each interlayer, there was an optimal LHI, when the LHI was lower than the optimal value, the interlayer was not completely melted; Otherwise, the high temperature at the interface can easily damage the CFRTP. All joints regardless of the types of interlayer demonstrated three fracture modes. Both the PA6 and epoxy interlayers can improve the heat distribution on surface of the CFRTP, leading to an increase in melting zone of the resins and thus a joint strength improvement. [ABSTRACT FROM AUTHOR]

• Confucian culture enhances the precision of analysts' earnings forecasts. • This impact is more pronounced in private enterprises. • This effect is more pronounced in enterprises situated in areas with higher levels of marketization. This article's findings reveal that Confucian culture enhances the precision of analysts' earnings forecasts. Tests for heterogeneity demonstrate that in private enterprises and more marketized samples, Confucian culture's governance impact is more significant. This study offers empirical support for the notion that Confucian culture serves as a vital external oversight mechanism for businesses. [ABSTRACT FROM AUTHOR]

• A tryptophan based hypercrosslinked polymer was prepared via facile one-step polymerization. • The polymer exhibited excellent adsorption selectivity and capacity for sulfonamides. • The polymer was used as sorbent for pipette tip solid phase extraction of sulfonamides. • The developed PT-SPE/HPLC method was validated in water, milk and meat samples. A novel tryptophan-based porous polymer is designed and synthesized via a facile one-step hypercrosslinking polymerization process, and applied as sorbent for extraction of trace sulfonamides in foodstuffs. The developed polymer has high surface area, large conjugate system, and abundant functional groups (e.g., π-π stacking, hydrogen bonding, hydrophobic and electrostatic attraction interactions), which endow it with superior affinity and high adsorption capacity for sulfonamides (16.16–59.29 mg g−1). The optimized SPE method is coupled with HPLC-DAD to create a sensitive and efficient protocol that provides good linearity (R2 ≥ 0.9979), low limits of detection, satisfactory recoveries (92.5–109.5 %) and high precisions (RSDs < 8.24). In addition, the newly proposed method greatly reduces the amount of adsorbent (2.0 mg) and organic solvent (2.0 mL) used. Adsorption kinetics, isotherms, and simulation calculations studies further reveal the presence of monolayer adsorption, chemical adsorption process, and multiple interactions. Thus, this work presents a polymer capable of multiple interactions for the pretreatment of trace sulfonamides in foodstuffs. [ABSTRACT FROM AUTHOR]

With rapid population growth and increased water pollution, the global water situation is deteriorating. Due to this risk, it is now crucial to efficiently remove organic contaminants from water. Metal-organic frameworks (MOFs), due to their unique qualities including adjustable porosity, large pore volume, and excellent adsorption and regeneration properties have recently gained significant scientific interest in the field of water treatment. The knowledge mapping, classification, synthesis, and design of MOFs are described in this review of the literature in order to clarify the advancement of MOFs in the removal of organic contaminants from aqueous solutions. To generate fresh concepts for the use of MOFs in the treatment of organic pollutants, the mechanism of adsorption of organic pollutants in MOFs is described, the application trends of MOFs for the treatment of organic pollutants are reviewed, and the bottleneck issues and application prospects of MOFs are compiled. [Display omitted] • Metal-organic frameworks efficiently remove organic pollutants from aqueous solutions. • Using Cite Space, a knowledge map of the literature on MOFs from 2012 to 2022 was visualized. • Discussed are MOFs synthesis and design routes that use less energy and solvent. • The mechanism of organic pollutant adsorption in MOFs is reviewed. • Challenges and future prospects of MOF briefly discussed. [ABSTRACT FROM AUTHOR]

Reaction of Cu(II) bromide and chloride with 2-amino-5-iodopyridine produced a family of 4- and 5-coordinate complexes. Magnetic susceptibility measurements show antiferromagnetic exchange via the bihalide superexchange pathway. [Display omitted] Reaction of 2-amino-5-iodopyridine (5IAP) with copper(II) bromide or chloride in alcoholic solution led to four coordination complexes: [(5-IAP) 2 CuCl 2 ](H 2 O) (1), (5-IAP) 2 CuBr 2 (2), [(5-IAP) 2 CuBr 2 ] 2 (3) and [(5-IAP) 3 CuCl 2 ](H 2 O) n (4). The compounds were characterized by single crystal X-ray diffraction and variable temperature magnetic susceptibility measurements. 1 crystallizes as monomeric units with the 5IAP ligands in the syn -conformation and one lattice water molecule. 2 also exhibits syn- conformation 5IAP ligands, but forms a common bromide bibridged dimer structure. 3 is a conformational polymorph of 2 with anti -oriented 5IAP ligands. Long Cu⋯Br contacts link the molecules into chains. 4 crystallizes with 1.67 lattice water molecules, disordered over three positions. All four compounds exhibit strong halogen bonding. Variable field and temperature magnetic data were obtained on 1 – 3. 1 is paramagnetic, with no indication of magnetic exchange down to 1.8 K. 2 is well modeled as an antiferromagnetic dimer (J/k B = −22 K) with significant antiferromagnetic interactions between the dimers. 3 is well modeled as a uniform antiferromagnetic chain (J/k B = −6 K) with weak interchain interactions. [ABSTRACT FROM AUTHOR]

The stretchable conductive materials with adjustable electromagnetic interference (EMI) shielding performance and other multifunctional integrated applications are remarkably desirable and challenging in flexible electronics. However, the existing stretchable materials often suffer from the decay of EMI shielding performance during the stretching process, which limits their practical applications. Meanwhile, it remains a great challenge to construct materials with ordered porous frameworks as integrated shielding devices. Incorporating porous structure will generate abundant interior surfaces/interfaces, facilitating multiple reflections of incident electromagnetic waves (EMWs). Herein, we employ ultrasound method to modify liquid metal (LM) with carbon nanotubes (CNTs), and further utilize an UV in-situ polymerization method to fabricate CNT@LM/polyacrylamide/gelatin (LMCPG) dual network hydrogel elastomer. The LMCPG hydrogel elastomer possesses high strength and durability, and its tensile strength reaches 117 kPa at 1033% strain owing to the high strength of the rigid network and the beneficial deformation ability of the flexible network. Deformable CNT@LM droplets elongate randomly during stretching process, which facilitates establishing more conductive paths. The EMI shielding capacity of the stretched elastomer can be controlled, achieving an intelligent on-off behavior, which exhibits a 211% increase at 200% strain in EMI shielding effectiveness (SE) compared with the undeformed state. Moreover, the LMCPG elastomer shows a significant triboelectric performance, which can provide power supply for flexible electronic devices, achieving an uninterrupted monitoring of the human body motion by devices. Therefore, as a flexible electronic material, it can offer a facile solution to achieve intelligent multifunctional integrated EMI shielding materials. [Display omitted] • A multifunctional integrated dual-network liquid metal-based hydrogel is fabricated. • This flexible electronic material can realize intelligent on-off EMI shielding. • This material achieves self-power and provide continuous human motion detection. [ABSTRACT FROM AUTHOR]

Interfacial strength between CFRTP and titanium is still weak and restricts its application in lightweight manufacturing. In this work, a new concept by in-situ constructing a sandwich interface with an interlocking structure and multi-chemical bonding to enhance interfacial strength was proposed. A novel method by designing and presetting interlayers with intersect-curved structures and dissimilar compositions was put forward to realize this in-situ construction. On the one hand, through presetting interlayer with designed intersect-curved structures, surface of CFRTP is changed from continued-heating to alternated-heating, which increases the maximum heat-input tolerance of CFRTP and prolongs cooling time. These contribute to deeper pinning depths with fully-filled resin into intervals, which greatly improve the interlocking strength at interface. On the other hand, by choosing an interlayer with a constituent chemically active with both CFRTP and base metal, the interfacial reaction is further enhanced, resulting in multi-chemical bonding including Fe-Ti and Fe-O at interface. This sandwich interface contributes to high strength of 45 MPa, which was 55% higher than non-interlayer samples in high heat input and four-folds higher than non-interlayer samples in low heat input. Compared with existing pre-treatment methods, this method was quite worth being recommended due to outstanding performance and low cost. [ABSTRACT FROM AUTHOR]

Traditional sludge disposal is currently restricted by the risk of secondary pollution. Sludge carbon material has gained widespread attention because of its low cost and environmentally sustainable properties. However, owing to the high ash content and low–energy density of sludge, sludge pyrolysis alone has certain limitations, and the performance of carbon materials needs to be improved. Herein, a sludge–cyanobacteria composite carbon (SCC) was easily synthesized, and the adsorption process of Cu(II) and Cr(VI) by SCC was examined. SCC-700-2-50% exhibited a high S BET (1047.54 m2/g) and developed pore structure rich in functional groups (such as –NH, –OH, and C–O). The combination of pore structure and functional groups improved the adsorption performance of SCC. The adsorption processes exhibited a synergistic effect in a binary system: the q m of Cu(II) and Cr(VI) were 386 mg/g and 341 mg/g, respectively, and the selectivity of Cu(II) adsorption by SCC was greater than Cr(VI). The adsorption process, examined by SEM-EDS, FTIR, and XPS analysis, indicated that Cu(II) as a cationic interface strengthens Cr(VI) adsorption through electrostatic interaction, and the anion Cr(VI) created a valid electrostatic shield against the electrostatic repulsion between H+ and Cu(II), facilitating Cu(II) adsorption. SCC had great reusability: Cu(II) and Cr(VI) adsorption capacity were 90% and 84%, of the initial adsorption capacity, respectively, after six cycles. This study demonstrates the prospect of SCC as a valid adsorbent for multiple heavy metal contaminations removal. [Display omitted] • High-performance SCC was prepared from sludge and cyanobacteria. • SCC exhibited high adsorption capacity and good regenerative abilities. • Cu(II) enhanced Cr(VI) adsorption by electrostatic interaction. • Cr(VI) promoted Cu(II) adsorption through electrostatic shielding. • SCC as an adsorbent is promising for removing of multiple heavy metal contamination. [ABSTRACT FROM AUTHOR]

Aims: The associations of moderate alcohol consumption, sleep duration, and tobacco smoking with coronary heart disease (CHD) among patients with type 2 diabetes mellitus (T2D) are not clearly clarified. The aims of the study were to evaluate the associations of lifestyle factors, hypertension, obesity, depression and sleep duration with CHD development among patients with T2D, and particularly, to examine the gender differences in risk factors for CHD.Methods: A total of 2335 T2D adults were selected from the 2012 National Health Interview Survey. Weighted univariate and multiple logistic regression analyses were used to estimate the odds ratios with 95% confidence intervals.Results: The CHD prevalence among patients with T2D was 14.2% (18.1% and 10.4% for males and females, respectively), which increased with age (10.3% and 19.6% for age groups 18-64 and 65+, respectively). After adjusting for other factors, weighted logistic regression analyses showed that CHD among patients with T2D was significantly associated with being male, older age, past smoking, long sleep duration, hypertension, and high cholesterol level. Furthermore, the significant association of older age, past smoking, hypertension and high cholesterol level were observed particularly in males, while the association of long sleep duration with CHD was only observed in females. Hypertension was associated with CHD for both genders.Conclusions: Gender, age, past smoking, long sleep duration, hypertension and high cholesterol level were significantly associated with CHD among T2D patients; however, such associations differed by gender. Such gender disparities should be considered in the prevention and treatment of T2D. [ABSTRACT FROM AUTHOR]

Aiming at the resolving long biofilm formation period problem of the moving bed biofilm reactor, a method for preparing modified carriers of bioflocculant doped in polylactic acid (PLA) to promote biofilm formation is proposed. The micron-scale porous structure is verified by optical microscopy and scanning electron microscope. The modified material also has nano-scale pores in BET test. FTIR shows that the bioflocculant modified carriers have amino carboxyl and polysaccharide functional groups. The biofilm formation time is shortened, and the removal efficiency of COD and ammonia nitrogen are 14.14–21.15% and 6.08–15.41% higher than that of polyethylene carrier. Extend DLVO theory shows that bioflocculant modified carriers have lower energy barrier (149.18 kT) than other modified carriers. By immersing modified carriers and ordinary carriers in the bioflocculant bacteria solution, the high-throughput sequencing reveals that the microorganisms attached on the carriers of bioflocculant doped in PLA have better biodiversity and abundance of functional gene expression than others. [Display omitted] • A preparation method of bioflocculant doped in PLA modified carrier is proposed. • Biofilm formation is promoted on bioflocculant-doped carriers. • The doping of bioflocculant increases the diversity of biofilm communities. • Extend DLVO theory shows that bioflocculant-doped carrier has smaller energy barrier. [ABSTRACT FROM AUTHOR]