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© 2019 Elsevier Ltd This article presents experimental and numerical results following blast tests on a polyether grade thermoplastic polyurethane (TPU). Aluminium alloy (AA) 2024-T3 skins were used as facings to enhance the blast resistance of sandwich structures with TPU cores and varying thicknesses. The experimental results highlighted an improvement in blast resistance with the addition of skins to the TPU core. Increasing the thickness of the TPU core in the sandwich panels served to increase the blast resistance of the structure. For example a 20 mm core offered a blast resistance that was 50.2% higher than an equivalent 5 mm core and 71.2% higher than a plain (i.e. no skin) 5 mm TPU core. Numerical simulations of the blast response of the TPU panels were conducted by converting the explosive loading regime applied to the panels to a simplified pressure pulse loading. Good agreement was obtained between the numerical and experimental results for the back face deflection profiles through the central cross-sections of the panels.

This chapter covers pertinent issues around the management of children with status epilepticus within and outside of specialist centres. A detailed overview of the work-up of a child in status epilepticus is presented. Additionally, the potential management of patients with refractory status epilepticus and super-refractory status epilepticus is evaluated. Furthermore, the chapter focuses on strategies to aid decision-making related to the practical challenges paediatric intensivists face, such as the suitability of extubating patients at the referring hospital, the decision to transfer patients to specialist centres for ongoing management, the role of neuroimaging, and about use of quantitative electroencephalogram (EEG) as a continuous neuromonitoring modality.

The mining activities significantly lower the sustainability in the stone mining region. Cleaner production (CP) is more likely to be proposed to achieve the sustainable development in the mining regions. Therefore, the stone mining industry has begun to implement many CP technologies and initiatives to tackle with ecological problems caused by the mining production. However, the CP practices do not solve the problems sufficiently, because of the low level of implementations by the stone mining companies, especially in the developing countries. This paper aims to establish a support framework for the stone mining industry to develop reasonable CP strategy and avoid inefficient CP practices. Our research provides a methodology for evaluating the CP level, including the principles of establishing indicator and standard system, the method of developing evaluation algorithm and the approach of data collection. A CP evaluation system is developed for the first time in the stone mining industry, which enables the methodology to be operationalization in the real evaluation process. The study also introduced the sensitivity analysis and confidence interval (ci) theory to ensure the reliability of the system and the validity of the evaluation results, respectively. A case study in Laizhou region of China illustrates how a CP strategy develops based on the CP evaluation results. The strategy has achieved collaborative optimization of various indexes of sustainability performance in the mining region.

This paper presents a study focusing on the perforation resistance of glass fibre-reinforced PEKK composites. Woven S-glass fibre (GF) reinforced poly-ether-ketone-ketone (PEKK) thermoplastic prepreg materials were manufactured using a dry powder prepregging method. Prior to impact testing and modelling, the properties of the composites were evaluated by conducting a series of quasi-static tests at room and elevated temperatures. Quasi-static tensile and perforation tests showed that the optimum weight fraction of PEKK, wf, is approximately 0.4, which gives the peak tensile strength and perforation resistance. Tests at elevated temperatures highlighted the excellent stability of these materials under extreme conditions. As expected, the energy required to perforate the targets increased with projectile diameter. Subsequent tests highlighted the severity of conically-shaped projectiles with the perforation resistance dropping under sharp object impact loading. A series of finite element models were also developed to predict the response of the glass fibre/PEKK composites to impact by projectiles based on different diameters and shapes. The predictions were validated against the experimental force-displacement traces and failure modes with good agreement.

The behaviour of concrete filled steel tube (CFST) columns has been investigated intensively against lateral and axial impact loading. However, there is a lack of knowledge on the impact response of the connection between such the column and steel beam. In order to close this gap, the most common connections with a partial depth end plate (PDEPCs), as a simple connection, and a flush plate (FPCs), as a moment resisting connection, were investigated under lateral impact loads. The long bolts were used to connect the CFST column to the beam as an alternative technique to the ordinary bolts. Here, eight specimens were tested under loading conditions with different locations and plate thicknesses. 3D finite element models were then developed and validated against the corresponding experimental results. Full range analyses of the connection response under the loading regime were then carried out using the validated FE models to examine the internal forces and the energy dissipation of the connections. The main findings are as follows: (1) the failure modes of both connection types investigated were similar at both loading locations only with slightly higher tearing fracture on the PDEPC; (2) using a thicker end plate increases the moment capacity of the connection but decreases its energy absorption; (3) the performance of long bolts provides the connection with appropriate ductility up to failure.

Lightweight cores, based on an egg-box core design, have been manufactured using a simple compression-moulding technique. Two types of composite prepreg were used to manufacture the core materials, these being a woven carbon fibre reinforced epoxy and a woven glass fibre reinforced epoxy. The resulting cores were of a high quality, exhibiting little or no wrinkling following the manufacturing procedure. Subsequent compression tests at quasi-static rates of loading showed that the compression strength of the core depended strongly on the level of constraint applied during testing, with sandwich panels based on composite skins bonded to an egg-box core offering a load-bearing capability that was more than double that of its unconstrained counterpart. The quasi-static compression strength of the carbon-based cores has been shown to be slightly higher than the glass fibre systems, particularly at higher core densities. Local splitting damage at cell joining regions and crushing of the cell of the egg-box structure was identified as the primary failure mechanism in the sandwich panels. Impact tests, conducted using a drop-weight impact tower, have shown that the compression strength of the egg-box cores is higher at dynamic rates of loading than at quasi-static rates. Here again, the local splitting and crushing was the primary mode of failure in the sandwich structures. Finally, the finite element technique has been used to model the mechanical response of these core designs under both quasi-static and impact loading testing conditions. Here, agreement between the predicted and observed responses was found to be good for both extremes of loading-rate.

Reliably predicting and estimating roof collapse in underground cavities such as mine goafs and power caverns is a serious concern in mining and geotechnical engineering fields. An analytical expression for a three-dimensional (3D) failure mode of a generic-shaped cavity crown is derived according to the upper bound theorem via limit analysis, where the Hoek-Brown yield criterion represents rock mass strength. The proposed method is validated by comparison against the extant research; the comparison also suggests that the roof profile plays a crucial role in cavity stability. Specific example is given to ellipsoidal cavity and the stability graph with respect to roof profile and cavity span is obtained and discussed. The effects of numerous factors on potential collapse are investigated based on the numerical calculation results. These results may provide workable guidelines for the optimization of roof shapes and support designs in minimizing rock detachment above cavity roofs in practice.

We presented the employment of ascorbic acid as the reducing agent for the in situ deposition of Ag nanoparticles on the surface of TiO2 nanotube arrays (TiO2 NTs/Ag). The structural investigation by scanning electron microscopy and transmission electron microscopy indicated that Ag nanoparticles with average diameters of 15 nm uniformly grew on TiO2 NTs walls. The possible formation mechanism of TiO2 NTs/Ag was proposed. UV–vis absorption and photoelectrochemical measurements indicated that the Ag sensitization extended the visible light absorption region, improved the photocurrent response, and enhanced solar-induced photoelectrocatalytic activities.

In order to improve the inherent brittleness of the conventional coarse-grained YAG transparent ceramics, nano-grained YAG transparent ceramics were fabricated at 5 GPa/450 °C using the super high pressure sintering technique. Their mechanical properties were investigated by nanoindentation and the Vickers indentation measuring methods. It was found that the nano-grained YAG transparent ceramics exhibited much better ductility compared with the coarse-grained counterparts. The grain-boundary sliding provides the main contribution to plastic deformations of nano-grained YAG transparent ceramics. Keywords: Nano ceramics, YAG, Nanoindentation, Mechanical property, Toughness

TiO2 nanotube arrays (TiO2 NTs) were prepared by a two-step anodization of titanium foils in ethylene glycol electrolyte. Then, CdS and Bi2S3 nanoparticles were deposited on TiO2 NTs by an one-pot solvothermal method. The investigations of X-ray diffraction and scanning electron microscopy indicated that CdS and Bi2S3 nanoparticles grew uniformly on the surface of TiO2 NTs. UV–vis absorption and photoelectrochemical measurements proved that the CdS and Bi2S3 co-sensitization significantly improved the visible light absorption, photocurrent response and photoelectrocatalytic removal of RhB and Cr(VI). In addition, the influence of Cd2+/Bi3+ concentration ratios on the photoelectrochemical performance of TiO2 NTs-CdS/Bi2S3 was investigated in detail. The TiO2 NTs-CdS/Bi2S3 (1:1) showed an optimal photoelectrochemical activity which could be attributed to the improvement of visible light response and charge separation derived from the coupling effect of CdS/Bi2S3 nanoparticles.

TiO2 nanotube arrays sensitized with Sb2S3 microcrystalline were successfully fabricated by a two-step process of photodeposition method followed by annealing treatment. The structural investigation by X-ray diffraction, scanning electron microscopy and transmission electron microscopy indicated that the Sb2S3 microparticles grew uniformly on the walls of TiO2 nanotubes. The amorphous Sb2S3 microspheres could be transformed into octahedral microcrystals after annealing treatment. The Sb2S3 modification of the TiO2 nanotube arrays resulted in an increase in visible light adsorption and photocatalytic activities toward degradation of methyl orange (MO) and rhodamine B (RhB) dyes under visible light irradiation.

In this work, we developed a novel environmentally friendly strategy toward solvothermal synthesis of 3D hierarchical Cu2FeSnS4 microspheres with the utilization of l -cystine, an amino acid, as a coordination agent and sulfur donor. The crystal structure, surface morphology and microstructure of the as-prepared products were investigated. The results showed that the 3D hierarchical Cu2FeSnS4 microspheres were composed of stannite nanosheets, and the average thickness of nanosheets was 100 nm. Moreover, the 3D hierarchical Cu2FeSnS4 exhibited high efficiency in the photodegradation of RhB under visible light illumination, suggesting a promising candidate for treatment of organic pollutants in waste water.

In order to comparatively assess near-neutral pH stress corrosion cracking (NNpH-SCC) resistance of pipeline steels with different strength, constant load tests in NS4 solution purged with 5%CO2–N2 gas mixture were conducted on American Petroleum Institute (API) grade X70, X80 and X100 pipeline steels. Experimental results show that pit cracks appeared on the surface of X70 steel and non-pit cracks appeared on X100 steel. However, for X80 steel both pit cracks and non-pit cracks were observed, but pit cracks dominated. The near-neutral pH SCC resistance decreased in the order of X70, X100 and X80 at the same applied stress level.

Ag nanoparticles modified TiO2 nanotube arrays (TiO2 NTs/Ag) were fabricated by a simple solvothermal method using ethanol as solvent and AgNO3 as precursor. The composition and structural investigation by X-ray diffraction, scanning electron microscopy and UV–vis diffusion reflection spectroscopy indicated that Ag nanoparticles were deposited into the TiO2 NTs. The TiO2 NTs/Ag exhibited more excellent photoelectrochemical and photocatalytic activities than those of the TiO2 NTs under UV and visible light irradiation. The enhanced photoelectrochemical activity of the TiO2 NTs/Ag could be attributed to the improvement of surface plasmon resonance absorption and charge separation derived from Ag nanoparticles.

Based on microsensor technology, a novel test rig was developed for the first time to measure real-time multi-point temperatures and relative humidities inside a cricket helmet worn by a human subject for obtaining the corresponding thermal and moisture mapping. Two types of helmets with and without ventilation openings were investigated to visualise the hot and wet spots clearly inside the helmet. The results show the clear influence of ventilation openings on effective reduction of the temperature as well as the relative humidity inside the helmet. Also, the subjective data were linked to the digital temperature and relative humidity measurements for possible assisting design of helmet with improved thermal comfort. The technology developed is a useful measurement approach to other head gears such as safety, fire fighter and motorcycle helmets, and further to study microclimate environments in close contact with human body.

Roll plane fluid slosh within a partly-filled tank with an elastic membrane restraining the free surface is investigated through development of a two-dimensional computational fluid dynamic and fluid-structure interaction (CFD-FSI) model. The air-membrane-liquid interaction analysis is performed to investigate effect of the membrane on the liquid cargo movement. Laboratory experiments were conducted on a circular tank with an elastic membrane-like restraint under harmonic lateral acceleration excitations. The validity of the CFD-FSI model is demonstrated on the basis of the laboratory-measured responses. The effectiveness of the membrane in limiting the fluid slosh is illustrated by comparing simulation results obtained for a circular tank with and without the membrane. It is shown that addition of the membrane could yield substantial reduction in the fluid cargo motion and thus roll moment, while increasing the fundamental slosh frequency by more than two times that obtained for the cleanbore tank.

Novel N and V co-doped TiO 2 mesosponge (N-V-TMSW) layers were successfully prepared by one-step hydrothermal treatment of TiO 2 nanotube arrays, and the phase composition, morphology and optical property were characterized by X-ray diffraction (XRD), Scanning electron microscopy (SEM), Atomic force microscope (AFM), X-ray photoelectron spectroscopy (XPS) and UV–vis diffusion reflectance spectroscopy (DRS). The crystal structure and density of states were studied by means of the first-principle pseudo-potential plane wave. The results indicated that titanium ions and oxygen atoms in TiO 2 were successfully substituted by vanadium ions and nitrogen atoms, respectively. The sample N-V0.1-TMSW showed a remarkable absorption in the visible light range of 400–600 nm and high visible photocatalytic activity

Study of fiber reinforced plastics (i.e. CFRP, BFRP and AFRP) for rectangular beams reinforcement effect, using the FRP were 90o vertically and 45o slantingly parceled 10 rectangular timber beams shear performance, recorded specimen failure process. This paper analyzes the different FRP reinforcement plies, different reinforcement on beam properties of specimen, failure mode, bearing capacity, load-deflection relationship and strain distribution. The results showed that: FRP changed beams brittle failure mode, improve the beam bending, shear performance, ultimate bearing capacity increased by 28.2%~55.1%, the stiffness of the specimen and also improved ductility. In addition, its more effective to paste the FRP sheets vertically than slantingly with the angle of 45°. Using FRP strengthening beams the performance of the method is effective, the method can significantly improve the performance of wood. To improve the utilization efficiency of wood, expand the application range of timber provides useful reference.

A coaxial quasi-elliptic bandpass filter (BPF) with controllable mixed electric and magnetic coupling is proposed in this paper. Adding a ridged transmission line section between the posts of inner resonator cavities is applied to enlarge the magnetic coupling between the adjacent resonators. On the other hand, the metallic caps on the top of the inner posts increase the capacitance loading of the coaxial resonators, thus not only decreasing its resonant frequencies and reducing the filter size, but also enhancing the electric coupling between the cavities. The proposed three-order BPF has two independently tunable transmission zeros (TZs). By simply adjusting the heights of the ridges and the distances between metallic gaps in a mixed coupled filter, the magnetic and electric coupling coefficients can be changed and two TZs can be tuned in the lower stopband, upper stopband, or both. The filter carries many advantages, such as compact size, low insertion loss, and high rejection level. A three-order mixe...

The chemical modified Idesia polycarpa Maxim. var. vestita Diels (IPMVVD) oil as a biodegradable lubricant was described in the paper. IPMVVD oil was modified by epoxidation and reaction of ring opening to resolve poor oxidative stability and low-temperature fluidity when vegetable oils as lubricants directly. The effects of the parameters in the process were studied, and then the product was evaluated. The results showed that the modified IPMVVD oil had higher viscosity index and superior oxidative stability comparing with unmodified oil; its mixtures with Dioctyl phthalate (DOP) offered a wide range of kinematic viscosities and lower pour point (-22°C), displayed preferable low temperature performance.

Linoleic acid (LA) was extracted and purified from Idesia polycarpa Maxim.var. vestita Diels (IPMVVD) oil by urea adduction fractionation, and the response surface methodology (RSM) was successfully employed to optimize the process. The optimal conditions for purification of LA from mixed fatty acids by urea adduction fractionation were as follows: a weight ratio of 4.4:1.0:1.0 (w/w/w) of methanol/urea/mixed fatty acids, a temperature of -5°C and a time of 24.6 h, respectively. Under these conditions the experimental LA yield (48.65%) agreed with the predicted value and the purity of LA was 98.74%.

The focus of this study is to analyse the stress distribution of corrugated web girder subjected to out-plane bending. Welded joining is considered in this study to connect the corrugated web and beam flange. As stress concentration is very critical for the prediction of fatigue life of the structure, this study provides preliminary results for further fatigue assessment of box-section girder bridge with such structural details. A finite element analysis based study has been conducted to trace the stress distribution along the corrugated web with varying thickness and cope hole details. The comparison with related simplified expression and typical stress concentration behaviours are outlined in this paper. Comments are given for the further consideration of presented stress characteristics in the fatigue design.

Problems regarding the combined axial force and bending moment for the behaviour of semi-rigid steel joints under service loading have been recognized in recent studies. As an extended research on the cyclic behaviour of a bolted endplate joint, this study is performed relating to the contribution of column axial force on the cyclic behaviour of the joint. Using finite element analysis, the deteriorations of the joint performance have been evaluated. The preliminary parametric study of the joint is conducted with the consideration of flexibility of the column flange. The column axial force was observed to significantly influence the joint behaviour when the bending of the column flange dominates the failure modes. The reductions of moment resistance predicted by numerical analysis have been compared with codified suggestions. Comments have been made for further consideration of the influence of column axial load in seismic design of bolted endplate joints.

Objective Our previous study showed that human umbilical cord blood–derived stromal cells (hUcBdSCs) expanded CD34 + cells in vitro. This study further explored the role of hUcBdSCs in vivo. Methods The cultured hUcBdSCs were infused into transplanted haploidentical mice to observe hematopoietic recovery and complications. Results The engraftment was faster in transplantation with hUcBdSCs than without hUcBdSCs. The numbers of fibroblast (CFU-F), granulocyte/monocyte (CFU-GM), erythrocytic (CFU-E), and megakaryocyte (CFU-Mg) colony-forming units were greater among mice transplanted with hUcBdSCs than without hUcBdSCs. The scoring of graft-versus-host disease was significantly lower in mice that had been subjected to transplantation with hUcBdSCs than without hUcBdSCs. The infused hUcBdSCs migrated to the bone marrow of the recipients. Conclusions These data indicated that hUcBdSCs improved hematopoietic reconstitution in haploidentical transplantation in mice.

Reinforced concrete construction is very common recently and extensively used both in industrial and commercial buildings. With the gradual rise in occurrences of fire accidents in recent years, a more thorough and quantitative understanding of the damage phenomenon in concrete structures is required. However, the mechanical behavior of concrete could actually be more complex under high temperature conditions than at room temperature. Restoration and reinforcement of the structures exposed to fire may have to be based on residual strength analysis and therefore require a correlation between temperature and mechanical properties. Thus, in order to meet the modern challenges of rapid engineering advances and societal development, further research on the concrete material and its structural behavior at high temperatures becomes extremely important. The present paper deals with investigations on the effect of high temperature exposure on the compressive strength of natural aggregate concrete. Experiments were conducted to study the compressive strength variations with increasing temperatures, up to 700 °C, and the subsequent cooling modes such as natural and spray cooling. Results show that the compressive strength gradually decreases with increasing temperatures. And micro-structural observations of the concrete specimens by means of scanning electron microscopy (SEM) were obtained. These test methods and results can be used for analyzing and investigating the behavior of recycled aggregate concrete with increasing temperatures.

The yield line analysis method is adopted to develop expressions for predicting yield load of bolted I-section web as the connecting face governs the failure of such connection. The proposed expressions are studied by varying the ratio, , of the bolt gauge width to the effective width of the web. By introduction of connecting face deformation limit, the comparison of the yield loads predicted by theoretical expressions and finite element analysis are demonstrated a satisfactory result for practical design. Thus, the yield load predicted by proposed expressions can be used as the basis for design of the bolted connections to I-section webs.

Fatigue in the very long life regime has assumed great significance in recent years particularly after it has been established that a fatigue limit doesn’t exist in most cases. The paper deals with investigations of gigacycle fatigue and near threshold fatigue crack growth behaviors of AA7075-T6, AA6061-T6 and AA2024-T3 Al alloys using piezoelectric accelerated fatigue at 20KHz. Experiments were conducted in air at room temperature on hourglass-shaped specimens under completely reversed loading conditions ( R = − 1 ) . It was noticed that failure continues to take place right up to the gigacycle ( 1 0 9 cycles) range, at nominal cyclic stresses. The high cycle fatigue fractures are generally rough in appearance and seen to initiate predominantly from the surface. Furthermore, they contain a significant number of voids, exhibit crystallographic faceting, and discernible fatigue striations. Gigacycle fatigue fracture of AA2024-T3, however, shows features of ductile tearing instead of striations. The studies also show that fatigue crack growth rates of small cracks are greater than those of large cracks for almost the same stress intensity factor range Δ K , and that some small cracks may grow at Δ K values below the large crack threshold in the near-threshold crack growth regime.

Problem statement: Free Met as one of the most limiting AA in dairy cows would be mostly degraded in the rumen. This study was to determine the effect of different levels of Rumen-Protected Met (RPMet) on dairy performance and serum amino acid metabolism. Approach: Thirty-six Holstein cows in similar condition were randomly assigned to six experimental treatments with six replicates each. Levels of RPMet in six treatments were 0(control), 14, 28, 42, 56 and 70 g day-1 per cow, respectively. Results: Treatment had no effect on percentage of milk protein, lactose and SNF. However, milk yield of cows fed 42 g day-1 RPMet was significantly higher than that of the control group and milk fat percentage was significantly increased with 56 g day-1 RPMet supplementation. There was the trend to decrease the concentration of serum amino acids except Met and Arg with the supplementation of RPMet. Serum EAA contents of the group supplementation of 42 g day-1 RPMet were lowest although there were no significant differences among all treatments. Serum BCAA concentrations of cows fed 28 g RPMet were significantly lower than that of the control group. Supplementation of 42 g RPMet could significantly decrease the concentration of NEAA and TAA compared to the control group. Conclusion/Recommendations: Supplementation of rumen-protected methionine improved dairy performance and promoted amino acid utilization in lactating cows in the present experiment. The optimal level of RPMet in the diet was 42 g per cow day-1.

The benefits of skeletal myoblast (SkM) transplantation for cardiomyoplasty are limited due to their decreased functional integration with host cardiomyocytes and the poor survival of implanted cells in ischemic hearts. However, little success has been achieved with respect to the strategies aiming to improve the efficiency of SkM transplantation. In this study, we demonstrated that LiCl-preconditioned SkMs resulted in significantly increased connexin 43 (Cx43) expression and gap-junctional communication with cardiomyocytes. Vascular endothelial growth factor (VEGF) expression of SkMs was significantly upregulated in response to LiCl. Furthermore, hydrogen peroxide induced SkM apoptosis and increased caspase-3 expression, whereas LiCl inhibited SkM apoptosis, resulted in the decrease of caspase-3 expression and promoted SkM proliferation. These effects of LiCl were mediated by inactivating glycogen synthase kinase-3β (GSK-3β), stabilizing the effector protein β-catenin and translocating it into the nucleus of SkMs, confirming that LiCl mimics canonical Wnt signaling. These findings suggest that LiCl preconditioning may be a novel strategy to optimize SkM function for cellular cardiomyoplasty in vitro.

In the paper, nanostructured, multimodal and conventional WC-12Co cermet coatings were sprayed by HVOF and the properties and structures of the coatings such as microhardness, microstructure, phase composition were compared. Finally sand solid and slurry erosion wear tests were carried out and their wear failure mechanisms were explored by XRD and SEM analysis. Research results show that microstructures of nanostructured and multimodal WC-12Co coatings prepared by HVOF are dense with little porosity, and their microhardness values are obviously higher than conventional WC-12Co coating. As well, it was found that nanostructured and multimodal WC-12Co coatings exhibited better sand solid and slurry erosion wear resistance in comparison with conventional coating and nanostructured WC-12Co coatings possessed the best sand solid erosion resistance properties at large impact angles and slurry erosion wear resistance. Testing results also show that although decarburization of WC occurred during spraying multimodal and nanostructured WC-12Co powders, the decarburization of WC for the nanostructured powder was more severe.

A series of experiments is carried out on the characteristics at the wedge bond interface. Bond lift-off characteristics are studied by using Scanning Electron Microscope with EDS-test. The characteristics of input impedance of PZT transducer are analyzed by the driving electric signal measured by Oscilloscope. Results show that the pattern of partially bonded material at the interface of ultrasonic wedge bonds exposed by peeling underdeveloped bonds simulates a torus with an unbonded central region. For the same machine variables, the input impedance and transforming power of the first wedge bond are greater than that of the second wedge bond. Some conclusions drawn by analyzing the input impedance and the power of PZT consist with the results gotten by testing microstructures at the interface.

In this paper, monotonic tensile and fatigue crack growth (FCG) studies were conducted on 7075-T6 Al substrates with and without bonded boron/epoxy patches. The Al substrates were machined to V-type side notch specimen. The presence of the pre-crack significantly decreased the plastic displacement and caused a slightly higher stiffness compared with the unnotched Al substrate. It was found that the repairs appeared to make the pre-cracked substrates slightly more plastic. The experimental results show that both static strength and fatigue life of the repaired aluminum substrates had been significantly increased for the bonded composite patches. The different patch-ply repairs were found to provide about a 5–14 times improvement in the fatigue life and a 2–4 times decrease in the stress intensity factor. The 4-ply-patch repaired specimen demonstrated its effectiveness in preventing static failure and increasing fatigue life of the cracked substrates. An analytical model, based on Rose's analytical solution and Paris' power law, was developed to predict FCG behavior of the repaired substrates. The analytical and experimental results are in good agreement.

Delta-6 fatty acid desaturases are rate-limiting desaturases involved in metabolic processes of fatty acids, and they are encoded by the FADS2 gene. In the current study, an F2 resource population of Gushi chickens crossed with Anak broilers was used to investigate the genetic effects of the chicken FADS2. Two adjacent single nucleotide polymorphisms (SNPs) (g.4290CG and g.4291CA) were identified in the transcriptional regulatory region of the FADS2 gene by means of polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and created restriction site-PCR-RFLP. Associations between the two SNPs with chicken fatty acid contents and growth traits were determined using linkage disequilibrium, haplotype construction, and association analysis. The two SNPs and their haplotype combinations were significantly associated with linoleic acid (C18:2), α-linolenic acid (C18:3), arachidonic acid (C20:4), body weight (BW)2, BW4, BW6, shank girth (SG)4, and breast bone length 4 (P0.05). These results suggested that the SNPs of the FADS2 gene affected the content of essential fatty acid in muscle, and played a role in the early-stage growth rate of chickens.

This paper presents a new model of parallel manipulator for manufacturing, whose mechanism comes from the general Stewart platform which has the advantages of high rigidity and high load capacity. A scheme of the link mechanism is also proposed to make the link structure very simple. The mechanism parameters are optimized by workspace analysis of the parallel mechanism. With the view of kinematics equivalence between parallel mechanism and serial mechanism, by way of hypothesis serial mechanism and branch hypothesis serial mechanism, an efficient kinematics algorithm has been developed. The problem, derived motion produced by the link structure, has also been solved conveniently.