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Abstract: Visible-light-driven one-dimensional (1D) anatase TiO2/Ag plasmonic photocatalyst was successfully prepared through a facile wet impregnation method. Experimental results indicate that Ag nanoparticles cover on the surface of TiO2 uniformly and the heterogeneous structure is formed efficiently. The obtained 1D anatase TiO2/Ag heterogeneous composites exhibit excellent photocatalytic activity (nearly 100% within 2h) for degradation of 2,4-dichlorophenol in wastewaters, which is ascribed to the suitable particle size of Ag nanoparticles in favor of enhancing the surface plasmon resonance and the heterogeneous structure advantageous of the separation of photogenerated electron–hole pairs. After reusage for ten times, the composites still present high photocatalytic activity, indicating the excellent stability. [Copyright &y& Elsevier]

Abstract: Few case-crossover studies were conducted in China to investigate the acute health effects of air pollution. We conducted a time-stratified case-crossover analysis to examine the association between air pollution and daily mortality in Anshan, a heavily-polluted industrial city in northeastern China. Daily mortality, air pollution, and weather data in 2004–2006 in Anshan were collected. Time-stratified case-crossover approach was used to estimate the effect of air pollutants (PM10, SO2, NO2 and CO) on total and cardiopulmonary mortality. Controls were selected as matched days of the week in the same month. Potential effect modifiers, such as gender and age, were also examined. We found significant associations between air pollution and daily mortality from cardiovascular diseases in Anshan. A 10μg/m3 elevation of 2-day moving average (lag 01) concentration in PM10, SO2, NO2 and CO corresponded to 0.67% (95% CI: 0.29%, 1.04%), 0.38% (95% CI: −0.06%, 0.83%), 2.11% (95% CI: 0.22%, 4.00%) and 0.04% (95% CI: 0.01%, 0.07%) increase of cardiovascular mortality. The associations for total and respiratory mortality were generally positive but statistically insignificant. The air pollution health effects were significantly modified by age, but not by gender. Conclusively, our study showed that short-term exposure to air pollution was associated with increased cardiovascular mortality in Anshan. These findings may have implications for local environmental and social policies. [Copyright &y& Elsevier]

Two-dimensional triaxial braided composite (2DTBC) often fails by external force from different directions in service. In this work, the in-plane compression failure mechanism of 2DTBC was studied along the axial (0°), off-axial (±60°) and perpendicular (90°) directions at quasi-static and high strain rate. The progressive failure process was recorded by infrared thermography with the final morphology using computer tomography technology. A three-dimensional mesoscale finite element model was established to simulate the initiation, accumulation and propagation of various damages. The results show that the in-plane compression strength, strain, energy absorption and failure mode of 2DTBC depends on whether there are main load-bearing (axial or braided) yarns directly transferring stress along load directions. The occurrence and development of localized damages can be captured by high-speed IR thermography and verified by final morphology. The in-plane failure mechanism of 2DTBC is induced by different dominating factors under different load directions, such as the out-of-plane movement of braided yarns, kinking effect at crimp positions, structure antisymmetry effect, buckling and shear instability. • Effect of main load-bearing (axial or braided) yarns during the in-plane compression. • Occurrence and development of damages captured by high-speed IR thermography. • Effect of yarns out-of-plane movement, kinking, buckling and shear instability. [ABSTRACT FROM AUTHOR]

[Display omitted] • Integral braiding and near-net forming of CFRP and CFRP/Al hybrid composite tubes. • In-situ and real-time failure mode analysis of CFRP and CFRP/Al composite tube under transverse impact. • Comprehensive effect of braiding angle, locailzed temperature rise, and ductile aluminum on the damage mechanism. High-speed infrared thermography, micro-CT characterization and full-scale mesostructural simulation were jointly applied to reveal the impact deformation and damage mechanism of composite tubes. Two different failure modes, namely the Impact Side Dominated (ISD) and Impact-/Non-impact Side (INIS), were found to have relation with the braiding angle and localized temperature rise. The hybrid effect can not only prevent resin fragmentation in the triangle region at the lateral side and the diamond region at the non-impact side, but also inhibit the CFRP damage development at the lateral and non-impact side. In small-angle braided tube, the impact-side rebound trend of CFRP layer leads to mismatch at the CFRP-Al interface, which results in opening delamination. In large-angle braided tube, the non-impact-side damage plays an important role in further load-bearing capacity. Apart from the structure effect, temperature rise has an effect on composite damage mode by degrading the localized matrix stiffness. [ABSTRACT FROM AUTHOR]

This study evaluated the compressibility of multislice CT (MSCT) datasets and its dependence on (1) slice thickness and (2) the use of three-dimensional (3D) vs. 2D JPEG2000 compression methods. Five thoracic CT datasets were obtained using a 16-detector MSCT scanner with a collimation of 0.75 mm (120 kVp, 90 mAs) and reconstructed at five slice thicknesses from 0.75 to 10.0 mm. These datasets were irreversibly compressed using a standard 2D JPEG2000 encoder and a developmental 3D JPEG2000 algorithm based on Part 2 of the JPEG2000 standard. Compression ratios ranged from 4:1 to 64:1. Image distortion was computed utilizing peak signal-to-noise ratio (PSNR) and the Sarnoff JNDmetrix visual discrimination model. For 2D compression, the thinnest sections were substantially less compressible than thicker sections for the same level of image quality, particularly at higher compression ratios. Applying 3D compression yielded consistently higher image quality in most cases compared to 2D compression at the same ratios. The advantage of 3D compression increased for thinner slices and higher compression ratios. These results indicate that 3D JPEG2000 (Part 2) compression offers substantial advantages over the current 2D JPEG2000 standard, yielding better quantitative image quality at similar compression ratios or comparable image quality at higher compression ratios. [Copyright &y& Elsevier]

Coiled tubing (CT) has been increasingly used in offshore oil and gas engineering. However, a number of issues should be solved to guarantee reliability and safety of the application. In this study, a mechanical model of CT-in-riser system is extracted from actual operations. Moreover, micro elements of the CT and riser are respectively analyzed using the infinitesimal method, and then a coupling model is derived. After differential equations are replaced by algebraic equations, the Newton iteration method is used to solve the coupling model. To validate above theory, an experimental platform based on the similarity laws is built. There are two types of experiments to be investigated, including the effects of fixed and floating boundaries, and the effects of three annular clearances. The results show that the force-out has a similarly increasing trend along the force-in under the fixed and floating boundaries, and the larger the annular clearances, the lower the transfer efficiency of the axial force. The maximum error between calculation results and experimental results is within ±5%, which validates the accuracy of the coupling model. The study will provide a theoretical support for CT's operations in offshore engineering. [ABSTRACT FROM AUTHOR]

To meet the demand of lightweight truss, thin-walled single-/double-/four-cell carbon fiber reinforced polymethacrylimide foam sandwich composite beams were manufactured by tubular braiding. Transverse impact damage and axial compression failure of the braided sandwich beams were investigated by finite element modeling, micro-CT detection, acoustic emission and infrared imaging characterization. It is found that impact damage concentrated at edges of the indentation region, internal CFRP walls and surrounding foams. Different from the continuous vertical wall in double-cell beam, cracks on the internal vertical wall of four-cell beam were suppressed at half height due to the discontinuous horizontal wall. During the axial compression, six failure modes were observed for non-impacted(0J) and impacted(40J, 60J, 80J) specimens, which were determined by the combined effect of impacted damages and inner configurations. And the inner configurations have an advantage over the transverse impact effect on the axial failure mechanism. Unlike the single-cell beams, the double- and four-cell counterparts did not present buckling or bending failures owing to the effective support from internal CFRP walls, however, more significant fracture was found at their outer CFRP layers due to the progressive mechanism of shear, tearing, splaying, and separation. • Integral braiding and net forming of sandwich beams with complex cross sections. • Mutual verification by micro-CT, FE analysis, and morphology characterization. • Real-time failure analysis by joint application of AE and IR method. • Effect of pre-impact and inner configurations on CAI properties of sandwich beams. [ABSTRACT FROM AUTHOR]

• Ultralight PAFP/GONRs-A aerogel was prepared facilely by solvothermal polymerization method. • The aerogel showed a low density, large specific surface area and high phosphorus content. • The aerogel presented an unexpectedly high adsorption capacity and selectivity for thorium. • Phosphonic groups play an important role in Th(IV) adsorption. • DFT calculations revealed the coordination modes of Th(IV) with the aerogel, confirming the experimental results. An ultralight three-dimensional porous network phosphonic acid functionalized polymer/graphene oxide nanoribbons aerogel (PAFP/GONRs-A) was prepared using trimethylolpropane trimethacrylate (TRIM) and vinylphosphonic acid (VPA) as monomers via solvothermal polymerization method for thorium capture from aqueous solutions. The synthesized aerogel presented a low density (10.6 mg cm−3), large specific surface area (433.2 m2 g−1) and high phosphorus content (18.2%). The adsorption process of Th(IV) on PAFP/GONRs-A was pH-dependent, spontaneous and endothermic, and well described by the pseudo-second-order kinetic and Langmuir isotherm model. Under optimal experimental conditions (10 mg of adsorbent dosage, 50 mL of solution volume, 240 min of contact time, 298 K of temperature), PAFP/GONRs-A presented an excellent high adsorption capacity of thorium, with maximum capacity of 457.9 mg g−1 at a pH of 3.0, and maximum thorium-selectivity of 87.1% at a pH of 2.0. The values of ΔG for Th(IV) adsorption on PAFP/GONRs-A were calculated to be −21.78, –23.32, −24.87 and −26.41 kJ mol−1 at 283, 298, 313 and 328 K, respectively. Density functional theory (DFT) calculations and X-ray photoelectron spectroscopy (XPS) revealed that Th(IV) ions were fixed in aerogel by coordinating with the P = O groups of PAFP/GONRs-A, and both 1:2 ratio of Th(IV) with the P = O ligands on the same graft chain and 1:4 ratio of Th(IV) with P = O ligands on two distinct graft chains could jointly contribute to the adsorption of Th(IV) on PAFP/GONRs-A. This work offers a facile approach for synthesizing the phosphonic acid functionalized graphene oxide nanoribbons aerogel and demonstrates that PAFP/GONRs-A has high potential as a candidate adsorbent for the capture of thorium from aqueous solution. [ABSTRACT FROM AUTHOR]

SiO x has aroused great attractions as a promising substitute for the anode materials of high-performance lithium-ion batteries (LIBs) because of the high specific capacity and the longer cycle life as well as relatively low volume expansion compared to Si. However, the unstable structure and poor conductivity of the SiO x lead to unideal electrochemical properties in LIBs, and thus hindering the widespread application of the SiO x anode. Herein, a facile approach has been put forward to prepare the high-performance mesoporous structure SiO x /carbon (m-SiO x /C) composites by electrospinning technique and sintering processes. The spherical SiO x nanoparticles are well anchored on the carbon fibers, and the reserved space can accommodate large volume expansion of the SiO x materials. Besides, the fibrous carbon materials can significantly enhance the conductivity for the SiO x anodes. Therefore, the resultant m-SiO x /C composites exhibit high discharge specific capacity of 1434 mAh g−1 at 500 mA g−1 with 67.5% capacity retention after 500 cycles and the good rate properties of 410 mAh g−1 at 2000 mA g−1. In consequence, the reasonable structural design and innovative fabrication technique can facilitate the practical application for the m-SiO x /C composites and further promote the comprehensive electrochemical performance of LIBs. [ABSTRACT FROM AUTHOR]

Background: Long-term glycemic variation in diabetes patients may have contributed to cancer incidence.Aim: In this study we aimed at the association between annual glycemic variation and the risk of cancer in Chinese patients with type 2 diabetes mellitus (T2DM).Methods: Subjects of this study were from an established population-based cohort of T2DM patients in Minhang District of Shanghai, China. Incident cancer were obtained from the Shanghai Cancer Registry. Glycemic variation was evaluated using the annual fasting glucose coefficient of variation (FG-CV), which was used as a time-dependent variable in a Cox regression model to estimate the associations with the cancer risk. Restricted cubic splines were used to explore potential non-linear associations.Results: A total of 2,140 incident cancers (1100 men and 1040 women) were identified from the 46,202 diabetes patients during 12-year follow-up. The annual FG-CV remained significantly associated with an increased risk of cancer, even after adjusting for the annual mean FG level. A significant non-linear association was found in male T2DM patients, and a significant linear association in female patients.Conclusions: The positive association of the annual FG-CV with the risk of cancer in T2DM patients indicate the importance to stabilize the FG level. [ABSTRACT FROM AUTHOR]

Low-velocity impact and flexure-after-impact (FAI) tests were performed on 2D plain woven fabric (PWF) and 3D orthogonal woven fabric (OWF) reinforced carbon fibers/epoxy composite beams while the electrical resistance measurement was applied during impact and FAI tests via four-probe technique to study the relations between resistance variation (RV) and residual mechanical properties. The impact tests (from 3 J to 9 J) showed that OWF specimens have better suppression of delamination than PWF, which was also evaluated through thermography and cross-sectional imaging method. Then FAI tests were implemented on impacted specimens while acoustic emission signals were captured. The residual flexural strength and modulus from the FAI tests were normalized by the values of intact specimens and compared with the RV from impact tests. The relations between electrical and mechanical properties revealed that the rise of resistance after the impact is an effective sign that indicates the reduction in the residual flexural strength and modulus of the composite beam. Moreover, the relation between RV and residual modulus is more effective than that with residual strength. [ABSTRACT FROM AUTHOR]

Oriented construction of high-performance mesoporous TiNb 2 O 7 (m-TNO) is important to the design innovation of anode material for next-generation lithium-ion batteries (LIBs) due to the high capacity and long cyclic life of m-TNO. However, the conductivity enhancement of m-TNO and thus accelerating Li+ transfer is still the key point to realize its practical application in LIBs. In this work, a synergistic strategy based on the single-core/dual-shell m-TNO@TiC@NC hierarchical structure is put forward, which is achieved by using m-TNO as host architecture as well as TiC and N-doped carbon layer (NC) as dual-shell layers. The results show that the m-TNO@TiC@NC hierarchical structure can not only provide an integrated conductive network to improve the conductivity of m-TNO, but also can establish a reinforced structure to maintain the anode stability. Besides, it is found that the m-TNO@TiC@NC composite has a high capacity of 328.6 mAh g−1 at 0.5 C after 200 cycles and a high-rate capacity of 186.4 mAh g−1 at 5 C by galvanostatic discharge-charge tests. Therefore, this kind of special single-core/dual-shell structure design can convincingly enhance the conductivity of m-TNO and facilitate the Li+ transfer rate, thus promoting electrochemical performances of LIBs due to the synergistic effect of dual-shell layers. Image 1 • The m-TNO@TiC@NC composite is achieved by using m-TNO as host architecture as well as TiC and NC as dual-shell layers. • The m-TNO@TiC@NC composite shows the single-core/dual-shell hierarchical structure. • The new-type ceramic material TiC is used as conducting layer. • The m-TNO@TiC@NC composite displays good electrochemical performance. [ABSTRACT FROM AUTHOR]

Interlayer friction is an important factor in producing rolls of glass-fiber woven fabric and strongly depends on the fabric structure and fabric interlayer contact mechanism. This paper investigates the effect of the initial contact state on the fabric/fabric friction coefficient by adjusting dislocations along circumferential and axial directions with a Capstan-based test setup. Results reveal that the maximal friction coefficient is approximately proportional to the height gradient between two adjacent yarns, while the minimal friction coefficient is less sensitive to the fabric structure. Moreover, a dislocation between fabric layers reduces both the maximal static and dynamical friction coefficients, and actively reciprocating a dislocation along the axial direction is an effective way of avoiding the interlayer friction from remaining at a low level. A dislocating mechanism is developed and introduced to a commercial fabric winding machine to verify the effectiveness of the proposed method in improving winding quality. [ABSTRACT FROM AUTHOR]

The activated carbon cloth (ACC@TNO) with flexible self-support structure, which is decorated by TiNb 2 O 7 (TNO) nanoparticle, is successfully obtained through hydrothermal reaction and calcination process in high temperature, and is used as the binder-free anode material of lithium ion batteries (LIBs). The morphology characteristic, pore structure properties and the phase structure of the ACC@TNO composites are detailedly studied by the scanning electron microscopy (SEM), Brunauer–Emmett–Teller adsorption/desorption measurement (BET) and X-ray diffraction (XRD). Meanwhile, the electrochemical properties of ACC@TNO composite are further tested by cyclic voltammetry and galvanostatic charge-discharge tests. As a result, the LIBs with ACC@TNO as anode material shows an initial discharge capacity of 356 mAh g−1 and an initial coulombic efficiency (ICE) of 87% at the current density of 0.5 C with the voltage window of 1.0–3.0 V. It also has been found that the reversible capacity can still keep as 290 mAh g−1 with the capacity retention of 81% after 500 cycles. Besides, when the cutoff voltage range is set to 0.01–3.0 V, the reversible capacity can reach 340 mAh g−1. Apparently, this work is of great significance for the exploration of the new anode materials with high performance and long cyclic life in next-generation LIBs. Image 1 • The ACC@TNO composite is obtained by epitaxially growing TNO particles on ACC surface like stab grown on the thorn. • The thiourea is use as a nitrogen source and sulfur source to treat the carbon cloth. • The ACC@TNO composite is binder-free anode material. • The ACC@TNO composite displays good electrochemical performance. [ABSTRACT FROM AUTHOR]