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Moving bed heat exchangers have been the economic alternatives for the granular flow in industries. To predict the heat transfer coefficients, a better understanding is required of the contact resistance (1/hws) and the penetration resistance (1/hso). In this work, the heat transfer coefficients were simulated using the finite volume method to investigate these resistances in both ordered and random packing sphere particles. It was found that, the 1/hws is determined by the effective thermal conductivity in the wall region, of which the thickness is around 3/22 particle diameters. Moreover, the 1/hso is affected by the heat capacity, thermal conductivities and particulate structures. The effect is reflected by two modified equivalent heat absorption coefficients (1/p1 and 1/p3) in granular flows. Generally, p1 is smaller in the ordered structure because the peak local solid fraction is higher, while p3 is smaller in the random structure due to the lower average porosity.

Discrete element method (DEM) is a powerful tool for solid granular, while the related heat transfer model requires more calibrations due to the over-simplified heat transfer path. In the present study, the calibration of overall thermal resistances (Rp) was conducted between a particle and the wall, where heat conduction in the particle interior and gap is more remarkable. It was found that, the existing DEM models should be improved in a wide range of the solid-to-gas ratio of thermal conductivity (ks/kg) and the dimensionless body distance (Sx/dp). The ideal heat transfer path may result in larger deviations as ks/kg > 250 or Sx/dp > 0, which can be only mathematically modified by the empirical factor. The general descriptions for modification are still required. To overcome the limit, an effective thermal conductivity model is proposed with certain formulas, where Rp is divided into two parts in the mixing phase zone and the gas zone.

A simplified finite volume method (SFVM) was developed for effective thermal conductivity in discrete particles. The solid granular was simplified as equivalent porous medium in control volumes, and local effective thermal conductivities were calculated to establish thermal resistance network. Finally, the overall effective thermal conductivity was obtained by the Kirchhoff's law. In SFVM, the heavy mesh work can be avoided, and particles are easily divided by regular grids, of which mesh size should go down to 1/11 of particle diameter. The local thermal resistance can be built based on the existing equivalent models, which are determined by the solid-to-gas ratio of thermal conductivity (ks/kg). As ks/kg

Human milk fat substitutes (HMFSs) are the structured lipids intended for infant formula. It provides energy and essential fatty acid for infant. HMFSs are mainly prepared by enzymatic method. In this study, we aim to explore the potential for producing HMFSs by fermentation using R. opacus. The results indicated that different compounds with chain length from 12 to 18, used as carbon source, could be incorporated into triacylglycerols directly. Polyunsaturated fatty acids in term of ARA, EPA, DHA could enter the kennedy pathway directly and involved in the biosynthesis of triacylglycerols. GC, UPLC-MS and 13C-NMR analysis demonstrated that typical structured lipids β-OPL (40.09%) was synthesized in R. opacus. Transcriptome analysis revealed that β-oxidation, fatty acid elongation and kennedy pathways existed in R. opacus. It was concluded that fatty acid supplied as carbon source could enter the kennedy pathways directly or via the de novo fatty acid biosynthesis pathway depending on the chain length, thus, affect the triacylglycerol species formed in the Rhodococcus opacus.

Automatic and early detection of flow influx during drilling is important for improving well-control safety. In this paper, a new method that can automatically analyze real-time drilling data and detect the flow influx event is presented. The new method combines the physics-based dimension reduction and time-series data mining approaches. Two kick indicators are defined, representing the drilling parameter group (DPG) and flow parameter group (FPG), respectively. Additionally, two real-time trend-analysis methods, the divergence of moving average (DMA), and the divergence of moving slope average (DMSA) are applied to quantify trend evolutions of the two indicators. The kick event is identified based on the anomalous trends held by the two kick indicators. A final kick-risk index (KRI) is calculated in real time to indicate the probability of kick events and to trigger the alarm. The method is tested against four offshore kick events. With KRI threshold setting as 0.8, the average detection time is 64% less than the reported detection time. The application of DPG kick indicator allows the early kick detection without additional downhole sensors or costly flow meters.

The present work investigated systematically the glass forming ability, the mechanical properties and the shear deformation of the TiZrHfCuBe high entropy bulk metallic glass (HE-BMG) with minor Sn addition. The results revealed that the glass forming ability and the thermal stability are enhanced by minor Sn addition but within a rather limited composition range. A nanoindentation study of the mechanical response in the (TiZrHfCuBe)1-xSnx (x = 0, 1, 2 and 3 at. %) HE-BMGs showed that the structural heterogeneity caused by Sn addition resulted in higher hardness, larger number of shear bands and smaller size of shear transformation zone, ascribing to the positive enthalpy of mixing between the Sn and Cu/Be elements. A statistical analysis of the serrated flow revealed that the chemical heterogeneities promote a relatively large population of shear deformation units and lead to multiple nucleation of shear bands. The present work might has implications in establishing the link between minor element addition and structure heterogeneity, which is of critical importance for understanding of shear banding behaviors in BMGs.

Visual evoked stimulation is an important method to study the response of optic nerve at the visual cortex. The visual cortex is closely related to the physiological state of the occipital lobe in brain. In the human, steady-state visual evoked potentials (SSVEP) and cerebral oxygenation changes, as measured by multi-modal of near-infrared spectroscopy (NIRS) and electroencephalography (EEG), are assessed to elucidate the relation between electrophysiological and haemodynamic responses to a checkerboard stimulus reversing. Further validation was done on ten healthy adults using a visual stimulation protocol to detect local hemodynamic changes and SSVEP component P100N135 amplitude. The experimental results show that there is a linear relationship between P100N135 amplitude and cerebral oxygenation concentrations in visual cortex. Within the 1-min stimulation period we find a decrease in P100N135-component amplitude, closely coupled to a decrease in the concentration of the oxyhemoglobin (HbO 2 ) and an increase of the deoxygenated hemoglobin (HbR).It provides a new way to clinical brain function detection and analysis through the multi-modal NIRS and EEG.

It has been demonstrated that mesenchymal stem cells (MSCs) have potent immunosuppressive capacities. But it is controversial whether differentiated mature stromal cells (SCs) share the immunosuppressive capacities. A previous study examined the ability of SCs from different human tissue sites to inhibit the proliferation of lymphocytes. The results are all positive but the mechanism isn't clear, and few mouse data have been published on this topic. Using an efficient mixed cell culture assay, our in vitro data show that the anti-proliferative ability of murine MSCs on lymphocytes is shared by mature murine SCs, i.e. chondrocytes and fibroblasts. Though conflicting results have been published, our results suggest that nitric oxide and IFN-γ are critical to the immunosuppressive effect. We also demonstrate that murine MSCs cultivated in chondrogenic differentiation medium still possess the anti-proliferative capacities on lymphocytes in vitro.

A significant number of literatures have concentrated on diverse issues related to Public–Private Partnership (PPP) both in China and abroad. However, there is no systematic analysis on the PPP research progress and status in Chinese journals, which is worth investigating because China is one of the largest PPP markets globally. In addition, there are many PPP publications in international journals based on the context of China. A comparative study is still missing between the PPP publications in Chinese journals and international journals. This paper hence aims to conduct a critical review of PPP publications from selected first tier Chinese journals and international journals. Based on a three-stage literature review research framework, 615 and 70 high quality research papers on PPP topics were selected from Chinese and international journals in the last decade between 2005 and 2014, respectively. Main research methods, research topics and research findings were then identified through content analysis and statistical analysis methods. It is found that in these two journals the frequently adopted research methods are case study , literature review , modeling , questionnaire survey and comparison ; and the popular research topics include PPP models and their application , risk management , financing and economic issues , l egal and procurement issues , government regulation and guarantee . Comparison analysis results show that in terms of order of popularity, there are more similarities in the research topics than research methods in Chinese and international journals. The outcomes of this paper contribute to the PPP body of knowledge through summarizing PPP research in Chinese journals and international journals in the context of China. In addition, the findings are valuable for Chinese researchers to embark future research on PPP. This paper also breaks the language barrier and enriches western researchers a better understanding of the research status of PPP in the context of China.

Moisture content (MC) and its variation have a significant influence on creep in wood. Therefore, reducing moisture absorptive/desorptive effect is one of the best means to minimize creep deformation in wood. Moreover, furfuration treatment of wood is one of the most economical methods to achieve this purpose. In this project, samples of Poplar wood (Populuseuramevicana) were treated with 30% furfuryl alcohol solution (furfurylated wood) and then tested for normal creep (NC) and mechanical sorptive creep (MSC) at different stress levels in several relative humidity (RH) conditions. Results from the experiment and analysis indicated that the normal creep performance of furfurylated wood was similar to that of classical untreated wood material. Nevertheless, furfurylated wood at different stress levels (less than 35%) or in different relative humidity environments did not follow MSC performance (i.e. creep deflection increases during moisture desorption while decreases during moisture absorption) of untreated wood and only exhibited wood NC characteristics (i.e. creep deflection increases continuously with time). Moreover, the maximum MSC deflection of furfurylated wood was 72.3% and 72.2% lower than that of untreated wood at the same 10% stress level and the same range of 65–98% relative humidity variation, respectively. The stress level was positively related to the deformations of instantaneous elastic, viscoelastic, viscous and bending creep, but negatively related to deformation of furfurylated wood creep recovery. Furthermore, it was also found that variation in RH did not have a significant impact on MSC deflection of furfurylated wood compared with untreated wood. The 4-element Burgers model and the 2-parameter Weibull distribution could well simulate the normal creep and creep-recovery responses respectively for furfurylated wood.

In this paper, the gravity-driven granular flow was investigated by discrete element method (DEM) in the moving bed heat exchanger with tube oscillation. The particle update, the particle contact and the heat transfer were all discussed around tube out-wall. Moreover, the heat resistance analysis was developed to reveal the heat transfer mechanisms. It was found that, tube oscillation can significantly improve heat transfer coefficients (h). The relative growth of locally optimal h varies from 59.2% to 22.6%, when the outlet velocity (u) ranges from 0.65 mm/s to 6 mm/s. In details, the heat transfer can be enhanced by tube oscillation due to the smoother flow in the upstream, the denser contact in the downstream and the more particle mixing inside the flow. However, the particle separation aside the tube has a negative effect simultaneously. Therefore, there is a best frequency (f) to optimize h. The frequency is inversely proportional to the amplitude (DA) and decreases with u. Furthermore, the larger DA can increase the best h. In the present study, the optimal h was obtained as f locates between 3 and 5 Hz at DA > 1 mm.

Workplace accidents would incur various losses to the injured workers and their families, employers and society. This study aims to investigate the magnitude of workplace accident costs to building contractors and identify factors influencing workplace accident costs of building projects. Data were collected using multiple techniques (structured interviews, archival records and questionnaires) from 47 completed building projects in Singapore. Data were analyzed using bivariate correlation analysis and moderated regression analysis. It is found that the average direct accident costs, indirect accident costs and total accident costs of building projects account for 0.165%, 0.086% and 0.25% of contract sum, respectively. It is concluded that workplace accident costs of building projects are influenced by accident rates, project hazard level, project size, company size and the involvement of sub-contractors. The findings of this study may enhance decision makers’ understanding of financial implications of workplace accidents in their building projects and motivate them to undertake accident prevention initiatives voluntarily.

Purpose To examine the incidence of age-related macular degeneration (AMD) and its associated factors in an adult Chinese population. Design Population-based study. Participants The Beijing Eye Study, which included 4439 subjects (age ≥40 years) in 2001, was repeated in 2006 with 3251 (73.2%) subjects participating. Methods Fundus photographs were graded using the International Age-related Maculopathy Epidemiological Study Group grading system. Main Outcome Measures Incidence of AMD. Results Gradable slides were available on 3049 (93.9%) subjects who participated in the survey of 2001 and again in 2006. The incidence of early, late, and neovascular AMD per eye was 2.6% (95% confidence interval [CI], 2.2–3.0), 0.1% (95% CI, 0.00–0.2), and 0.1% (95% CI, 0.00–0.2), respectively. The incidence of early, late, and neovascular AMD per person was 4.2±0.4% (95% CI, 3.5–5.0), 0.1±0.1% (95% CI, 0.0–0.2), and 0.1±0.1% (95% CI, 0.0–0.2), respectively. By multivariate analysis, incident early AMD was associated significantly with greater age at baseline ( P = 0.01; odds ratio [OR], 1.03; 95% CI, 1.01–1.06), smaller optic disc size ( P = 0.007; OR, 0.50; 95% CI, 0.30–0.83), smaller scleral spur distance ( P = 0.04; OR, 0.59; 95% CI, 0.36–0.98), and hyperopic refractive error ( P = 0.057; OR, 1.15; 95% CI, 1.00–1.33), with the latter being significant only marginally. It was not associated with the systemic parameters of gender, body height, body mass index, region of habitation, level of education, profession, smoking, arterial blood pressure, diabetes mellitus, fasting blood concentrations of glucose, triglycerides, high-density or low-density lipoproteins; or the ocular parameters of intraocular pressure, retinal arterial and vein diameters, retinal microvascular abnormalities, amount of nuclear cataract, cortical cataract or subcapsular cataract, pseudophakia, glaucoma, nonglaucomatous optic neuropathy, retinal vein occlusions, size of the beta zone of parapapillary atrophy, or progression of the zone of atrophy during the follow-up from 2001 to 2006. Conclusions Hyperopia, short interscleral spur distance, and small optic disc size were, beside older age, the main factors associated with incident early AMD. This may point to a small globe size, potentially in relation to a firmly attached vitreous, playing a role in early incident AMD. Financial Disclosure(s) The authors have no proprietary or commercial interest in any of the materials discussed in this article.

In this study, EU-1 zeolite was successfully synthesized via a quasi-solid state approach and assembled to catalyst for the C8 aromatics isomerization process. The catalytic properties were tuned through careful modification of the acidity of EU-1 zeolites and metal-doping of the catalyst. It was shown that EU-1 was an excellent candidate for the C8 aromatics isomerization process due to its unique structure. In addition, steam treatment of EU-1 at 450–500 °C could optimize the acidic properties of the catalyst, hence enhance its catalytic performance. The effect of the amount of Pt on ethylbenzene conversion was studied and the optimum amount was determined to be about 0.3–0.4 wt%. It was confirmed that EU-1 zeolite prepared via a quasi-solid state approach and then dealuminated by steam treatment had better activity and selectivity than conventional mordenite (MOR) zeolite and could be an excellent candidate for C8 aromatics isomerization.

Purpose To estimate the 5-year incidence of cataract and cataract surgery in an adult Chinese population. Design Population-based study. Participants The Beijing Eye Study 2006 included 3251 (73.2%) subjects (≥45 years) of 4439 subjects who participated in the 2001 survey and returned for re-examination. Methods Nuclear, cortical, and posterior subcapsular lens opacities were assessed based on standardized slit-lamp–based photographs and retroilluminated photographs of the lens using a modification of the grading score of the Age-Related Eye Disease Study. Main Outcome Measures Incidence of any type of cataract and of cataract surgery. Results The 5-year incidence of nuclear cataract was 5.98% (95% confidence intervals [CI], 5.96%–6.00%), that of cortical cataract was 11.14% (95% CI, 11.12%–11.17%), that of posterior subcapsular cataract was 5.47% (95% CI, 5.45%–5.48%), and that of cataract surgery was 2.01% (95% CI, 2.00%–2.02%). The incidence of any cataract (16.82%; 95% CI, 16.79%–16.86%) was significantly associated with higher age ( P P P = 0.78), smoking ( P = 0.95), or alcohol consumption ( P = 0.12). Differentiation into the 3 cataract types revealed that the incidence of nuclear cataract additionally was associated with rural region ( P P P = 0.02). The incidence of cataract surgery was significantly ( P Conclusions As in white persons, the age-adjusted incidence of all types of cataract types increased with age and it was associated with female gender. When compared with data in the literature, the incidence rates of all cataract types did not vary markedly between Chinese in greater Beijing and white persons. In contrast, the incidence of cataract surgery was considerably lower in this Chinese population. Financial Disclosure(s) Proprietary or commercial disclosure may be found after the references.

Five non-symmetrical PCN pincer palladium(II) complexes [PdCl{C6H3-2-(CH NR)-6-( OPR 2 ′ )}] (R = m-ClC6H4, R′ = Ph (2a); R = Ph, R′ = Ph (2b); R = i-Pr, R′ = Ph (2c); R = m-ClC6H4, R′ = i-Pr (2d); R = (S)-1-phenylethyl, R′ = Ph (2e)) have been easily prepared in only two steps from readily available m-hydroxybenzaldehyde and characterized by HRMS, 1H NMR, 13C NMR, 31P NMR and IR spectra. The molecular structures of 2a and 2b have been further determined by X-ray single-crystal diffraction. The obtained Pd complexes were found to be effective catalysts for the Suzuki and copper-free Sonogashira cross-coupling reactions which could be carried out in the undried solvent under air.

A composite coating of WC/Hadfield steel was fabricated through centrifugal casting process to improve the impact wear resistance of Hadfield steel under the conditions of low or medium impact energy. The interfacial structure between WC ceramic particle and the steel matrix was analyzed with scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX) and X-ray diffraction (XRD). The impact wear tests at different impact energy were carried out on a MLD-10 type impact wear rig to investigate the wear-resistant properties of three kinds of composites with different WC particle sizes. For comparison, the wear tests of Hadfield steel were also carried out under the same conditions. The results show that WC particles are partially dissolved in the steel during centrifugal casting. The elements W, C and Fe in steel react to form new carbides such as Fe 3 W 3 C or M 23 C 6 , which precipitate around former WC particles forming fine particles during subsequent solidification. So the interface between WC particles and Hadfield steel matrix is a strong metallurgical bonding. The composite reinforced with smaller WC particles has better impact wear resistance than that of Hadfield steel regardless of impact energy level. Whereas, the composite reinforced with larger WC particles has better impact wear resistance property than that of Hadfield steel when the impact energy is small but an opposite result is gained when the impact energy is higher. So, it is very essential to choose suitable size of WC particles as reinforcement in Hadfield steel to make the composite material more durable in the service conditions.

The phase diagram of the system InCl3/1-methyl-3-butylimidazolium chloride (MBIC) was constructed by DSC method. A clear colorless and transparent ionic liquid was experimentally observed in InCl3/MBIC system with about mole fraction of InCl3 x=0.50 at ambient temperature. Both Raman scattering and ab initio calculations indicate that InCl4− is the predominant indium-containing species in this liquid.

This paper presents a novel method for the synthesis of nitrate sodalite from an uncalcined, dry Al 2 O 3 –2SiO 2 gel powder at low temperature. Nitrate sodalite particles were successfully synthesized utilizing a dry-gel conversion method (DGC) and characterized by SEM, HRTEM and SAED techniques. The mechanism of formation of the nitrate sodalite and its cation exchange capacity (CEC) were studied and the experimental results indicate that the nitrate sodalite particles were composed of numerous small grains, incompletely crystallized and arranged in a spherical cage-like structure.

A new chromogenic reagent tribromocarboxyarsenazo has been synthesized and the chromogenic reaction of this reagent with zirconium studied. In the medium of 0.5 mol/1 HCl, a blue complex is formed by the reaction of zirconium with tribromocarboxyarsenazo. The maximum absorption of the complex is at 633 nm, and the apparent molar absorptivity is 4.8 × 10 4 1/mol/cm. Beer's law is obeyed over the zirconium concentration range 0–18, μg/25 ml. The method has been applied to the determination of zirconium in aluminum, copper and magnesium alloys with satisfactory results.

Our earlier theoretical work on the relative muon capture between heavy and light fission fragments is extended by including 2p{sigma} states as well as 1s{sigma}. We calculate about 0.8% population of the 2p state in the heavy fragment with negligible change from our earlier two-state basis regarding the ls population of light and heavy fragments.