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The objective of the present study was to determine the optimal incubation conditions for Gloiopeltis furcata culture. Three experiments, each lasting 30 days, were conducted to study the effects of photoperiod (6:18, 8:16, 12:12, 14:10, and 16:8 h light/dark), different wavelengths of LED light (blue, green, yellow, red, and white), and solar radiation filtered through different plastic films (blue, green, yellow, red, and white) on the growth and photosynthetic pigment content of G. furcata. The results of these experiments demonstrated that the growth rate of G. furcata was significantly higher under 14:10 and 16:8 light/dark than under 6:18 and 8:16 light/dark, while the pigment content of G. furcata was significant higher under 6:18 and 8:16 than under 14:10 and 16:8 light/dark. The growth rate of G. furcata was the lowest when the algae were exposed to blue LED and the highest under yellow LED illumination, while the phycobiliprotein content was the highest under blue LED and the lowest under yellow LED. Solar radiation filtered through different plastic films had no significant effect on the growth rate of G. furcata, but affected its pigment content. The results indicate that a photoperiod of 12 h or more of light and yellow LED are the optimal parameters for culturing of G. furcata thalli on land.

Two-dimensional (2D) layered bismuth (Bi) with a thickness-dependent direct bandgap (0–0.55 eV) has attracted ever-increasing research interest in electronics, energy storage and conversion devices. However, few-layer Bi nanosheets (NSs) are easily oxidized under ambient conditions. Searching for a convenient and low-cost strategy to produce high-quality few-layer NSs in large scale is of great importance to prompt its practical applications. Herein we report that the liquid-phase exfoliation method with acetone solvent is suitable for fabricating 2D thin and low-oxidized Bi NSs. Next, we assemble the produced Bi NSs into all-solid-state supercapacitors (ASSPs). The as-prepared devices exhibit a volumetric capacitance of 36.8 F cm−3, together with excellent volumetric energy and power densities. The volumetric capacity can be further enhanced up to 68.7 F cm−3 by compositing with CNTs. The maximum volumetric energy and power densities are 9.5 mW h cm−3 and 203.2 W cm−3, respectively. Moreover, we demonstrate that the Bi/CNT devices exhibit outstanding flexibility (79.0% retention of the initial capacitance at 180° bending) and superior cycling stability (82.2% retention of the initial capacitance after 20 000 cycles), demonstrating the great potential of Bi/CNTs for high-performance flexible ASSPs.

Water pollution caused by CrO42− has become a global concern due to its high aqueous solubility and good mobility in the underground environment. Recently, water stable zirconium based metal–organic frameworks (Zr-MOFs) have been tested as adsorbents to remove pollutants from contaminated water. However, the low adsorption capacity of Zr-MOFs towards ionic pollutants is unsatisfactory due to their neutral nature. Herein, a cationic Zr-MOF (Zr-C-MOF) was obtained by directly introducing a pyridinium salt as a ligand with an impressive ion exchange capability. Zr-C-MOF demonstrated enhanced acidic resistance and selectively high adsorption of CrO42−. The characteristics of the obtained Zr-C-MOF were confirmed via various techniques including PXRD, FT-IR spectroscopy, 1H-NMR spectroscopy, TGA, SEM, EDX and XPS. Batch adsorption studies have been conducted to gain a deep understanding of the kinetics mechanism, pH effects, adsorption isotherm and the effects of other competing ions. The kinetics and adsorption isotherm of CrO42− adsorption onto Zr-C-MOF were found to well fit the pseudo-second-order rate equation and the Langmuir model, respectively. The comparison of FT-IR, PXRD, SEM, EDX and XPS results of the samples before and after CrO42− adsorption revealed the adsorption mechanism of the anion exchange process.

Backgrounds Pregnancy termination during the second trimester in patients with placenta previa and placenta accreta spectrum (PAS) is a complex and challenging clinical problem. Based on our literature review, there has been a relative increase in the number of such cases being treated by hysterotomy and/or local uterine lesion resection and repair. In the present study, a retrospective analysis was conducted to compare the clinical outcomes when different management strategies were used to terminate pregnancy in the patients with placenta previa and PAS. Methods A total of 51 patients who underwent pregnancy termination in the second trimester in Beijing Obstetrics and Gynecology Hospital between June 2013 and December 2018 were retrospectively analyzed in this study. All patients having previous caesarean delivery (CD) were diagnosed with placenta previa status and PAS. Results ① Among the 51 patients, 16 cases received mifepristone and misoprostol medical termination, 15 cases received mifepristone and Rivanol medical termination, but 1 of them was transferred to hysterotomy due to failed labor induction, another 20 cases were performed planned hysterotomy. There was no placenta percreta cases and uterine artery embolization (UAE) was all performed before surgery.② There were 31 cases who underwent medical termination and 30 cases were vaginal delivery. Dilation and evacuation (D&E) were used in 20 cases of medical abortion failure and in all 30 cases of difficult manual removal of placental tissue. ③ A statistically significant difference was found among the three different strategies in terms of gestational weeks, the type of placenta previa status, main operative success rate and β-HCG regression time (P Conclusions Terminating a pregnancy by vaginal delivery through medical induction of labor may be feasible if clinicians have an overall understanding of gestational age, the type of placenta previa status, the type of placenta accreta, and patients concerns about preserving fertility. A collaborative team effort in tertiary medical centers with a very experience MDT and combined application of multiple methods is required to optimize patient outcomes.

Background Breast cancer (BC) has a marked tendency to spread to the bone, resulting in significant skeletal complications and mortality. Recently, circular RNAs (circRNAs) have been reported to contribute to cancer initiation and progression. However, the function and mechanism of circRNAs in BC bone metastasis (BC-BM) remain largely unknown. Methods Bone-metastatic circRNAs were screened using circRNAs deep sequencing and validated using in situ hybridization in BC tissues with or without bone metastasis. The role of circIKBKB in inducing bone pre-metastatic niche formation and bone metastasis was determined using osteoclastogenesis, immunofluorescence and bone resorption pit assays. The mechanism underlying circIKBKB-mediated activation of NF-κB/bone remodeling factors signaling and EIF4A3-induced circIKBKB were investigated using RNA pull-down, luciferase reporter, chromatin isolation by RNA purification and enzyme-linked immunosorbent assays. Results We identified that a novel circRNA, circIKBKB, was upregulated significantly in bone-metastatic BC tissues. Overexpressing circIKBKB enhanced the capability of BC cells to induce formation of bone pre-metastatic niche dramatically by promoting osteoclastogenesis in vivo and in vitro. Mechanically, circIKBKB activated NF-κB pathway via promoting IKKβ-mediated IκBα phosphorylation, inhibiting IκBα feedback loop and facilitating NF-κB to the promoters of multiple bone remodeling factors. Moreover, EIF4A3, acted acting as a pre-mRNA splicing factor, promoted cyclization of circIKBKB by directly binding to the circIKBKB flanking region. Importantly, treatment with inhibitor eIF4A3-IN-2 reduced circIKBKB expression and inhibited breast cancer bone metastasis effectively. Conclusion We revealed a plausible mechanism for circIKBKB-mediated NF-κB hyperactivation in bone-metastatic BC, which might represent a potential strategy to treat breast cancer bone metastasis.

This paper presents an optimal solution for the alignment of horizontally curved track in a high-speed maglev line, in which the minimum length of the curved track is taken as a major objective fun...

Modification of silica gel by butanedioic anhydride (SiO2–BDAH) results in efficient adsorbents for removal of U(VI), Th(IV), and Eu(III) from aqueous solutions. SiO2–BDAH was characterized by Fourier Transform infrared spectroscopy, elemental analysis, N2 adsorption–desorption isotherms, thermogravimetic analysis, and potentiometric titration. The effect of contact time, pH, and initial concentration of radioactive solutions and temperature on the adsorption capacity of the sorbent was investigated. The sorption equilibrium times of U(VI), Th(IV), and Eu(III) onto SiO2–BDAH were 1.5, 2, and about 10 h. The sorption percentages of U(VI), Th(IV), and Eu(III) increased with increased pH from 1 to 5. The sorption process of U(VI), Th(IV), and Eu(III) can be described by the Langmuir model, with sorption capacities of 5.10 × 10−5, 5.06 × 10−5, and 3.44 × 10−5 mol/L, respectively. The enthalpy and entropy changes were all positive, whereas the free energy changes were negative. This study indicated that SiO2–BDAH can remove U(VI) and Th(IV) at the same time in the presence of multiple ions from waste water quickly.

Purpose To study the quality of our human ovarian tissue cryopreservation technique as performed in the first official "International Fertility Protection Centre" in China in patients with certain cancer types using a mouse model, and to find the best site for tissue transplantation in the mouse. Methods Thirty-six BALB/C female nude mice were randomly divided into 3 groups, group 1: control group; group 2: ovariectomized group; group 3: ovarian tissue transplantation group. Seventy-two pieces obtained from six ovarian tissue samples from each of three cancer patients were transplanted into the ovarian bursa cavity (OBC), the subcutaneous thigh (TS) and the subcutaneous neck (NS) and removed after 1.5 and 2.5 months, respectively. Follicular growth rate (FGR), total follicle surviving rate (TFSR), tissue recovery rate (TRR), antral follicles (AF), follicle stimulating hormone (FSH), estradiol (E2) and anti-Mullerian hormone (AMH) levels were measured. Results No significant differences in FGR, OBC, NS (p > 0.05); TFSR was 100% in OBC, NS and TS. No significant differences in TRR (p > 0.05); AF were found only in OBC; TFSR was 100% after transplantation; significantly higher FGR in the 2.5 months compared to the 1.5 months-group (p

Cementitious coatings are widely used to protect steel structures from fire, yet there are concerns about its performance in earthquakes, where partial damage to the fire protection could potentially compromise the fire safety of steel structures. In this paper, results from a series of experiments are presented to quantify the damage in cementitious fire resistive coatings under cyclic loading. Steel plates of various sizes are first tested under cyclic loading, which exhibit greater damage than the specimens subjected to monotonic loading. A steel column is subjected to cyclic load along with another subjected to monotonic load are both coated with 20 mm thick cementitious fire resistive material and tested to investigate the damage patterns in a more realistic setup than steel plates. Tensile transverse cracks on the flange, vertical cracks along the flange tip, and interfacial debonding of the coatings are the main forms of coating damage, which appear with a lower story drift ratio compared to the monotonically loaded column specimen.

This paper presents a general framework for the dynamic analysis of high-speed maglev trains running on elastic transitional viaducts, a complicated problem that lacks an efficient analysis tool. Unlike the straight and circular tracks, both the curve radius (CR) and height difference (HD) between the outer and inner rails vary along the transitional track. To start, the motion of each vehicle of the train running over a transitional track is expressed by a set of trajectory coordinates, with their orientations given in the Euler angles as functions of the CR and HD. The elastic transitional viaduct is simulated by finite elements in the global coordinates. For the maglev trains, the electromagnet force-air gap model is used to account for the interaction and coupling effect between the moving vehicles and supporting viaduct. By applying the proposed framework to the Shanghai maglev line (SML), the dynamic responses of the maglev vehicles running on the transitional viaduct are studied and compared with those on the straight and circular viaducts. Moreover, the effects of transitional track length and cant deficiency on the coupled system are investigated. The results show that for vehicles running on the transitional track, the levitation forces and vehicle’s angular velocity are highly related to the rate of change of HD of the track. The length of the transitional viaduct affects significantly all the vehicle’s responses. The increase of deficient cant angle causes a sharp increase in the responses of the transitional viaduct in both the radial and rotational directions.

Power transformer is the key equipment in the power system. In recent years, transformer explosion occurred frequently, most of which caused fire and resulted in heavy losses. Research in this field is still in the initial stage. To analyze the anti-explosion performance of transformers, an equivalent load model for transformer arc fault is firstly proposed in this paper, and the relevant numerical simulation is carried out. Fluid-structure interaction is considered in the numerical simulation, and finally the load distribution field and the structural response characteristics of the transformer are obtained for two typical arc fault locations.

This chapter presents an evaluation of the hysteretic performance of high-strength steel (HSS) H-section and box-section columns via cyclic loading test and finite element simulation. Trilinear moment–curvature hysteretic model for HSS H-section and box-section columns is proposed.

The emergence of impact investing over the past decade has been accompanied by increased interest in impact measurement to understand both social and financial returns. One of the constantly re-occurring themes in the research on impact measurement is the tension between financial return and social/environmental mission. However, we challenge this binary view by addressing the following questions: is the profit/purpose trade-off dilemma an immutable feature of impact investing? And, if so, how are investor-investee relationships negotiated through those tensions to keep the impact measurement process flowing productively? Using an exploratory multi-round Delphi Method study (15 panellists) and 22 semi-structured interviews, we discover a new set of impact measurement practices, which are relational and non-transactional in nature. These two levels of engagement, the transactional and the relational, occur in sequence and reinforce each other, ultimately creating both instrumental and intrinsic value. In the end, we propose the Transactional-Relational Spiral model and encourage further research and validation.

Objectives To evaluate the severe outcomes in pregnancies with pernicious placenta previa and prior cesarean delivery, and to analyze the predictive examinations and prevention strategies regarding severe complications in these women. Design Multicentre retrospective cohort study. Setting Thirteen hospitals in China. Population Selected 747 women with pernicious placenta previa and prior cesarean history. Methods The basic data relating to pregnancy, the examinations during gestation and the outcomes were collected and analyzed. Main outcome measures Outcomes including massive bleeding, placenta implantation and hysterectomy were monitored. Results Our results showed that placental implantation occurred in 47.5% of patients and the hysterectomy rate was 10.4%. The incidence of massive bleeding and blood transfusion was 55.8% and 64%, respectively. The women with placenta implantation predicted by both ultrasound and MRI had higher blood loss than those diagnosed only by either one of the examinations. Surprisingly, vascular occlusion had no effect on the occurrence of severe hemorrhage and hysterectomy. The latter was even higher in the vascular blocking group compared to that in the non-blocking group (34.2% and 8.6%, respectively). Conclusions: The pregnancies with pernicious placenta previa and prior cesarean delivery, had a dramatically higher risk of placenta implantation, hysterectomy and massive hemorrhage. MRI combined with ultrasound examination presented high accuracy in predicting severe outcomes in these patients. Vascular occlusion does not appear to be an effective approach to prevent severe outcomes. Surgical hemostasis should be the key goal in blocking massive bleeding, preserving the uterus and improving the prognosis of the patients.

Background Aberrant activation of the NLRP 3 (nucleotide‐binding oligomerization domain, leucine‐rich repeat–containing receptor family pyrin domain‐containing 3) inflammasome is thought to play a causative role in atherosclerosis. NLRP 3 is kept in an inactive ubiquitinated state to avoid unwanted NLRP 3 inflammasome activation. This study aimed to test the hypothesis that pharmacologic manipulating of NLRP 3 ubiquitination blunts the assembly and activation of the NLRP 3 inflammasome and protects against vascular inflammation and atherosclerosis. Since genetic studies yielded mixed results about the role for this inflammasome in atherosclerosis in low‐density lipoprotein receptor– or apolipoprotein E–deficient mice, this study attempted to clarify the discrepancy with the pharmacologic approach using both models. Methods and Results We provided the first evidence demonstrating that tranilast facilitates NLRP 3 ubiquitination. We showed that tranilast restricted NLRP 3 oligomerization and inhibited NLRP 3 inflammasome assembly. Tranilast markedly suppressed NLRP 3 inflammasome activation in low‐density lipoprotein receptor– and apolipoprotein E–deficient macrophages. Through reconstitution of the NLRP 3 inflammasome in human embryonic kidney 293T cells, we found that tranilast directly limited NLRP 3 inflammasome activation. By adopting different regimens for tranilast treatment of low‐density lipoprotein receptor– and apolipoprotein E–deficient mice, we demonstrated that tranilast blunted the initiation and progression of atherosclerosis. Mice receiving tranilast displayed a significant reduction in atherosclerotic lesion size, concomitant with a pronounced decline in macrophage content and expression of inflammatory molecules in the plaques compared with the control group. Moreover, tranilast treatment of mice substantially hindered the expression and activation of the NLRP 3 inflammasome in the atherosclerotic lesions. Conclusions Tranilast potently enhances NLRP 3 ubiquitination, blunts the assembly and activation of the NLRP 3 inflammasome, and ameliorates vascular inflammation and atherosclerosis in both low‐density lipoprotein receptor– and apolipoprotein E–deficient mice.

Based on boron-dipyrromethene (BODIPY), taking 2-hydroxy-N-(2-hydroxyphenyl)benzamide as recognition site, a new fluorescent probe HHPBA-BODIPY aimed at sensitively detecting Cu ions was designed, synthesized and characterized.The emission spectra of HHPBA-BODIPY exhibited an intensive green fluorescence around 510 nm, with a maximum absorption near 500 nm. When Cu

The aim of this study was to investigate early clinical features and risk factors for cesarean scar pregnancy (CSP). Study group of 206 CSP patients out of 6853 women with early pregnancies, diagnosed from 2014 to 2016 was compared with a randomly selected control group of 412 patients. Early clinical features for CSP were vaginal bleeding (OR: 9.65; 95% CI: 5.67-16.41), lower abdominal pain (OR: 3.8; 95% CI: 1.52-9.54) and increased white blood cells (OR: 1.30; 95% CI: 1.12-1.50). Important risk factors for CSP were artificial abortion within the last pregnancy (OR: 4.13; 95% CI: 2.23-7.66), 0 ∼ 1 year and 2 ∼ 3 year interval between present and last pregnancy (OR: 2.27; 95% CI: 1.11-4.67 and OR: 2.15; 95% CI: 1.15-4.03). Pregnancy problems are important issues within the scope of 'Gynecological Endocrinology'. Vaginal bleeding and lower abdominal pain, although unspecific, could be early clinical symptoms of CSP, especially if main risk factors exist such as abortion within the last pregnancy and short interval to the last pregnancy. Knowing this can help for prevention and early diagnosis CSP which can reduce life-threatening complications such as massive hemorrhage and can avoid hysterectomy. Consequence also must be to avoid unwanted pregnancies by using effective contraception, especially in risk patients.

Polyvinyl butyral (PVB) is often used in laminated glass and windscreen for its high ductility and good adhesion with glass. Previous studies have shown that the mechanical properties of PVB are both rate-dependent and temperature-dependent. To investigate mechanical properties of PVB material under different strain rates and different temperatures, a series of tensile tests on 1.52 mm-thick PVB specimens are carried out, covering designed engineering strain rates from 0.1/s to 300/s and temperatures from −30 °C to 40 °C, using an Instron high-speed servo-hydraulic testing machine and temperature box. Corresponding true stress-true strain curves are obtained. The testing results are then analyzed and empirical formulae are derived for key mechanical property parameters. Finally, based on G’Sell model, dynamic constitutive equations are given at different temperatures for PVB.

This study presents a more realistic modelling of the maglev-based high-speed railway line in Shanghai, China. Focus is placed on an accurate simulation of the two subsystems: the train subsystem i...

High strength steel reinforced concrete (HSRC) column refers to steel reinforced concrete column using high strength steel with its yield strength over 420MPa. So far, research on seismic behavior of HSRC columns is limited. This paper presents experimental and numerical studies on seismic behavior of HSRC columns. Two Q460 high strength steel reinforced concrete columns have been tested under low cyclic loading with constant axial compression ratio of 0.3. Flexural failure is observed in the test. From the hysteresis curves, the specimens exhibit good ductility and satisfactory energy dissipation capacity. Displacement ductility factors are larger than 2. When load descends to 85% of the peak load, the ultimate drift ratios of two specimens are 1/29 and 1/26 respectively, which meet the requirements of Chinese Seismic Design code (GB 50011). To study the seismic behavior of HSRC columns more comprehensively, a numerical model has been established for simulating the experiment using OpenSees, which adopts nonlinear beam-column element and fiber model. The numerical result fits the test data well, which validates the effectiveness of numerical model. Parametric study is then carried out to further investigate the seismic behavior of HSRC columns.

This work investigates the delamination behaviour of polyvinyl butyral (PVB) laminated glass under quasi-static loading based on a cohesive zone model (CZM) with an isotropic bilinear traction - separation (T – δ) law. It presents a 2D model of a through-cracked tensile (TCT) test within an implicit finite element framework of the commercial software ANSYS. Test results from literature are used to calibrate the adhesion properties of the PVB-glass interface in a numerical cohesive zone approach. The previous TCT tests were performed at a loading rate of 6 mm/min and a temperature of approx. 22 °C. Three different PVB adhesion grades, i.e., BG R10 (low), BG R15 (medium) and BG R20 (high) are considered. Given the uncertainty in the identification of adhesion parameters, including interfacial fracture energy, cohesive strength and stiffness, a parametric analysis is conducted quantifying the influences of model parameters on the simulation results. The study allows for decoupling of individual parameters in the calibration. Then, interfacial fracture energies and cohesive strengths of the PVB-laminated glass are calibrated by matching the force – displacement curves of the numerical simulations with those from the TCT experiments. One representative case was chosen for each adhesion grade. We obtain interfacial fracture energies of 425 J/m2, 650 J/m2 and 1000 J/m2 for BG R10, BG R15 and BG R20 PVBs, respectively, while the corresponding cohesive strengths are 3 MPa, 5 MPa and 10 MPa, respectively. Moreover, based on numerical simulation results, the conversion of energy during the delamination process is extracted and discussed. The mixed-mode delamination mechanism is investigated by calculating the mode I and mode II energy release rates with respect to different PVB thicknesses and adhesion. The results show that the proportion of the mode I energy release rate is around 30%∼40% of the total energy release rate at the stable delamination stage and increases with PVB thickness. The presented study contributes to the adhesion properties of various types of PVB interlayers reported in open literatures and proposes a methodology for the unique identification of adhesion properties.

The transparent ionomer material SentryGlas® or SG for short is widely used as interlayers in laminated glass and is also a potential adhesive in laminated connection. The material’s shear modulus is of practical interest before glass breakage because it allows a shear transfer between glass components. Due to the viscoelasticity behaviour of the material, its modulus is significantly dependent on the working conditions. This work investigates the effects of temperature, time, and strain rate on SG’s shear small-strain modulus from the point of practical application. The shear property at room temperature is obtained from the results of shear tests. Based on the viscoelastic theory, the time and temperature dependence within the actual application range is quantitively determined from DMA measurements. The glass transition temperature associated with modulus decline is then recalibrated. The effect of strain rate is also qualitatively measured. Finally, the time-temperature dependent equations of shear modulus are applied to numerical simulation of a long-term loading test on framed ionomer interlayer laminated glass.

The recent historic turn in management has seen scholars debate whether, why, and how history can be useful to managers (Wadhwani, Suddaby, Mordhorst, & Popp, 2018; Argyres, De Massis, Foss, Fratti...

Polytetrafluoroethylene (PTFE)/Kevlar fabric or fabric composites with excellent tribological properties have been considered as important materials used in bearings and bushing, for years. The components’ (PTFE, Kevlar, and the gap between PTFE and Kevlar) distribution of the PTFE/Kevlar fabric is uneven due to the textile structure controlling the wear process and behavior. The components’ area ratio on the worn surface varying with the wear depth was analyzed not only by the wear experiment, but also by the theoretical calculations with our previous wear geometry model. The wear process and behavior of the PTFE/Kevlar twill fabric were investigated under dry sliding conditions against AISI 1045 steel by using a ring-on-plate tribometer. The morphologies of the worn surface were observed by the confocal laser scanning microscopy (CLSM). The wear process of the PTFE/Kevlar twill fabric was divided into five layers according to the distribution characteristics of Kevlar. It showed that the friction coefficients and wear rates changed with the wear depth, the order of the antiwear performance of the previous three layers was Layer III>Layer II>Layer I due to the area ratio variation of PTFE and Kevlar with the wear depth.

In this paper, an analytical model for determining the iso-damage curves for framed monolithic glass panels subjected to blast loading is proposed. Two typical damage levels corresponding to different conditions in GSA/ISC are classified, namely (a) the glass crack limit and (b) glass fragments invading with a certain velocity. The nonlinear dynamic responses and failure modes of framed monolithic glass under different blast loadings are firstly analysed numerically. Then critical states of glass panel in both impulsive region and quasi-static region of the pressure-impulse (P-I) diagram are defined. Based on the energy balance approach, an analytical method is proposed for determining the pressure asymptote and the impulse asymptote of framed monolithic glass for different damage levels. The proposed method is verified through comparison with published experimental data and numerical results. The method can be applied for any framed monolithic glazing with different dimension and thickness and provides a practical approach for engineering design and hazard level estimation of framed monolithic glass against blast loading.

Anti-ram bollard systems, which are installed around buildings and infrastructure, can prevent unauthorized vehicles from entering, maintain distance from vehicle-borne improvised explosive devices (VBIED) and reduce the corresponding damage. Compared with a fixed bollard system, a removable bollard system provides more flexibility as it can be removed when needed. This paper first proposes a new type of K4-rated removable anti-ram bollard system. To simulate the collision of a vehicle hitting the bollard system, a finite element model was then built and verified through comparison of numerical simulation results and existing experimental results. Based on the orthogonal design method, the factors influencing the safety and economy of this proposed system were examined and sorted according to their importance. An optimal design scheme was then produced. Finally, to validate the effectiveness of the proposed design scheme, four dynamic impact tests, including two front impact tests and two side impact tests, have been conducted according to BSI Specifications. The residual rotation angles of the specimen are smaller than 30o and satisfy the requirements of the BSI Specification.

Universal couplings cause additional moments on the sleeve shaft of work roll. The problem becomes more obvious in the wide and heavy plate mill due to the large tilt angle and the great rolling torque, which may affect the deflection of roll system and the screw-down load deviation. Aiming at the structural characteristics of the drive system of a 5000 mm wide and heavy plate mill, additional moment models acting on the work roll are established, and the influence coefficients of the additional moment of the main drive system are obtained according to Mohr integral method. The screw-down load deviation affected by the additional moment is calculated based on the influence function method. Results show that the additional moment of the work roll drive end has little effect on the screw-down load deviation. And the fluctuation period of the additional moment is 180° with the input shaft rotating. The additional moment enlarges with the tilting angle increasing. If the tilt angle is equal to 4.82°, the vertical additional moment is about 8.5% of the output torque of motor shaft, while the horizontal additional moment is about 4.2% of that.

Steel reinforced concrete column has been widely applied in high-rise buildings and long-span structures. In this paper, an analytical study is carried out for predicting the axial compressive behavior of steel reinforced concrete (SRC) column using cross-shaped steel section with flanges. Firstly, respective material models were established for different components in the composite cross-section, including highly confined concrete, partially confined concrete, unconfined concrete, steel section as well as steel reinforcement. For highly confined concrete, the interaction mechanism between steel section and confined concrete has been investigated, based on which a uniaxial stress-strain relation is established. For partially confined concrete, as the hoop may not yield, an iterative procedure is applied to calculate the real stress in hoops and then the effective lateral confining pressure. For steel section, the biaxial stress state is considered in the material model. Based on section analysis method, a unified analytical model is then proposed and verified through comparison of analytical results with test results on SRC and partially confined SRC (PSRC) short columns. At last, a simplified method for calculating the real stress of the hoop and then the strength of partially confined concrete was proposed to avoid the iterative process and save the computing time.

Polytetrafluoroethylene/poly(methyl methacrylate) (PTFE/PMMA) composites were prepared by a self-curing method. The influence of heat treatment processes on the friction and wear behaviors of PTFE/PMMA composites against bearing steel balls were studied by a ball-on-disk tribometer. The thermal performance of PTFE/PMMA composites with heat treatment was analyzed by Thermogravimetric Analysis (TGA). The surface morphologies and element distribution of PTFE/PMMA composites in a PMMA matrix were detected by Field Emission Scanning Electron Microscopy (FE-SEM) and Energy Dispersive Spectroscopy (EDS). The results indicated that the wear rates of PTFE/PMMA composites with different heat treatments significantly declined compared with the unheated treatment composite. The wear rate of the PTFE/PMMA composite decreased firstly and then increased with molding temperature and time increasing, and reduced with the molding pressure increasing. The main wear mechanisms of PTFE/PMMA composites with different heat treatments were fatigue wear and abrasive wear.

PVB-laminated glass has been widely adopted for building windows as safety glass due to its significant post-crack load bearing capacity. To achieve a better understanding of the mechanical behaviour of framed PVB-laminated glass under explosion, a series of field blast tests were carefully designed and conducted aiming to study the dynamic responses and failure modes of framed PVB-laminated glass subjected to various blast loadings. The reflected overpressure and displacement time histories were measured in the tests. In particular, DIC technology was adopted to record the 3-D deflection field of the glass panel, which is essential for analyzing the dynamic response feature of laminated glass panels under blast loading. Three typical failure modes, i.e. global flexural failure, local punching failure and mixed failure, were identified and corresponding failure mechanisms were analyzed. Finally, the test results were used to check the effectiveness of different design approaches. The results from this study can provide reference for further blast resistant analysis and design for framed PVB-laminated glass.

The dry sliding tribological properties of hybrid PTFE/Kevlar fabric composite were investigated under ambient and different vacuums, loads, sliding velocities, and temperatures. The results showed that hybrid PTFE/Kevlar fabric composite displayed lower friction coefficient in vacuum than that in ambient and satisfactory antiwear performance in low vacuum and middle vacuum, but poor antiwear performance in high vacuum. In vacuum, the friction coefficient and wear rates decrease with the increasing of sliding velocities, loads and temperature within a certain range. But the higher temperature of 60 °C detriments the friction coefficient and wear rate. Textile structure also has an obvious influence on the antiwear performance. The main wear mechanism in vacuum including plastic deformation, micro-cutting, fatigue damage and abrasive wear.

Maglev, offers competitive journey-times compared to the railway and subway systems in markets for which distance between the stations is 100-1600km owing to its high acceleration and speed; however, such systems may have excessive vibration. Field measurements of Maglev train-induced vibrations were therefore performed on the world's first commercial Maglev line in Shanghai, China. Seven test sections along the line were selected according to the operating conditions, covering speeds from 150 to 430km/h. Acceleration responses of bridge pier and nearby ground were measured in three directions and analyzed in both the time and frequency domain. The effects of Maglev train speed on vibrations of the bridge pier and ground were studied in terms of their peak accelerations. Attenuation of ground vibration was investigated up to 30m from the track centerline. Effects of guideway configuration were also analyzed based on the measurements through two different test sections with same train speed of 300km/h. The results showed that peak accelerations exhibited a strong correlation with both train speed and distance off the track. Guideway configuration had a significant effect on transverse vibration, but a weak impact on vertical and longitudinal vibrations of both bridge pier and ground. Statistics indicated that, contrary to the commonly accepted theory and experience, vertical vibration is not always dominant: transverse and longitudinal vibrations should also be considered, particularly near turns in the track. Moreover, measurements of ground vibration induced by traditional high-speed railway train were carried out with the same testing devices in Bengbu in the Anhui Province. Results showed that the Maglev train generates significantly different vibration signatures as compared to the traditional high-speed train. The results obtained from this paper can provide good insights on the impact of Maglev system on the urban environment and the quality of human life nearby.

The blast resistance of point-supported laminated glass curtain wall has been investigated by means of field blast tests and numerical simulation. Nine site blast tests were carried out, considering two types of glass thickness and six TNT charges ranging from 0.4 to 30 kg. The overpressure and displacement time histories were measured and the failure modes were observed. The overpressure obtained from the measurement panel exhibited a typical pattern of near-field blast with a steep increase followed by a rapid decay within a few milliseconds. The displacement response of the laminated glass panels increased with the increase in the TNT charge almost linearly in the smaller tests (scaled distance ranging 4.5–7 m/kg1/3), which was in line with the increase in the blast impulse in these tests. The failure mode of the point-supported laminated glass panels was featured by tearing off of the polyvinyl butyral layer around the support area, while the glass shards still adhered to the polyvinyl butyral interlayer. Nonlinear dynamic finite element simulation agrees reasonably well with the results from the blast tests. Severe stress concentration has been predicted to occur at the rim of the support holes, leading to initiation of failure at these supports, and this also agrees with the failure mode observed from the blast test. Finally, parametric studies are carried out to investigate the influence of TNT charge weight and the geometric parameters of the panel on the blast response of the glass curtain wall.

The anti-ram bollard system (ABS) is installed around the perimeter of buildings and infrastructures to prevent the penetration of unauthorized vehicles and reduce the blast and debris caused by the vehicle-borne improvised explosive devices (VBIED). Comparing with the fixed anti-ram bollard system (FABS), the auto-lifting anti-ram bollard system (AABS) has the advantage to be set down automatically to allow authorized vehicles passing on. In this paper, a configuration of K4-rating AABS is proposed and a finite-element model is developed to simulate its performance. Differences between vehicle model and real vehicle, effects of boundary conditions are both taken into account. The effectiveness and accuracy of the numerical simulation are validated through predicting the results of relevant experiments. Based on the verified numerical model, 32 groups of numerical experiments of K4-rating AABS are investigated using an orthogonal array L32 (48×81). The order and significant levels of nine affecting factors are identified on the basis of the range analysis and variance analysis, respectively. It shows that gaps between substructure and outer sleeve, wall thickness of substructure, wall thickness of steel tube, diameter of steel tube and thickness of stiffening ribs have significant influences on the behavior of AABS. The optimal design is proposed according to the orthogonal analysis.

To evaluate hysteretic performance of welded Q690D high-strength steel H-section columns, cyclic loading test and numerical simulation were carried out. Firstly, cyclic loading test was performed on two H-section Q690D HSS welded columns with nominal axial compression ratio of 0.35. The observed failure mode is elastic–plastic local buckling of component plates. Hysteretic curves and skeleton curves of the test specimens show that the tested columns have a good energy dissipation capacity. Then, a finite element model was developed to simulate the hysteretic behavior of Q690D beam-columns and verified through comparison of numerical and experimental results. It is found that residual stresses are of ignorable influence on the ultimate bearing capacity of beam-columns. With the verified finite element model, extensive parametric analyses were conducted to investigate the effects of component plate slenderness ratio, column slenderness ratio and axial force ratio on the hysteretic performance of the Q690D H-section columns. Based on the observation and analyses of the experimental and numerical hysteretic curves, a trilinear moment-curvature hysteretic model for welded Q690D steel H-section column was proposed.

Suitable solvent and the related solution thermodynamics of fosfomycin phenylethylamine (FPEA) are essential for its purification by cooling crystallization. Two candidate solvents of ethanol and water are systematically investigated and compared, including the solubilities in them from 278.15 to 348.15 K with an interval of 5 K and the dissolution enthalpies at different concentrations at 303.15 K, which were measured using a static equilibrium method and solution calorimetry at atmospheric pressure, respectively. In addition, densities of FPEA in the two solvents at a diluted region were accurately measured for compositional analysis of equilibrium samples. Meanwhile, we explored the thermal stability of solid FPEA by using thermogravimetry. Crystalline FPEA was thermal stable blow 378.15 K and its molar heat capacity increased from 42.2 to 119.7 J·mol−1·K−1 when heated from 308.15 to 363.15 K, as determined by differential scanning calorimetry. When FPEA was further heated, it started to decompose at around 453.15 K without prior melting and then continued to decompose in several steps with the subsequent increase of temperature. When it was dissolved in the two solvents, endothermic effect was observed and the molar enthalpy of dissolution FPEA in ethanol at infinite dilution was about 2 kJ/mol higher than that in water, suggesting more hydrogen bond formation in water. The molality solubility of FPEA in water was generally higher than that in ethanol, but the difference decreased significantly with the increase of temperature. From 347.15 down to 279.15 K, the solubility in water decreased from 1.292 to 0.237 mol·kg−1, while that in ethanol decreased from 1.247 to 0.084 mol·kg−1, which justified the suitableness of using ethanol as the solvent for the cooling crystallization of FPEA with respect to product yield. The thermodynamic functions of solubility and solvation processes were estimated. An integrated approach by van't Hoff plot, enthalpy-entropy compensation analysis and solution calorimetry showed that enthalpy-entropy compensation was occurring in the dissolution of FPEA in both solvents and the enthalpic effect dominantly controlled the Gibbs free energy change of the process.

The ionomer material is widely used as interlayers in the laminated glass, and its tensile property plays a decisive role in the post-fracture response of the laminated glass. Since the ionomer material is a kind of polymer, its mechanical behaviour is highly affected by strain rate and temperature. In this work, two series of uniaxial tensile tests, low strain rate series (10−3s−1~10−1s−1) and medium to high strain rate series (1 s−1~800 s−1), were conducted over a wide temperature range (−40 °C~80 °C). Details of the test setup and corresponding true stress-true strain curves are presented. Characteristic mechanical parameters are then identified to evaluate the temperature and strain rate effects. It was found that higher strain rate and lower temperature result in higher strength and stiffness but lower ductility. The material shows apparent plasticity as more than 80% deformation is unrecoverable. Based on the observations, G’Sell model is adopted to build the temperature-dependent dynamic constitutive model, which is then validated through comparison between the predicted results and the published test data.