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Magnesium (Mg) and its alloys are considered as ideal biodegradable materials due to their excellent mechanical properties and biocompatibility. In order to improve the surface properties to allow better adaptation to the surrounding tissue of the body, surface modification has played a significant role in satisfying multiple clinical requirements such as corrosion resistance, biocompatibility, and antibacterial ability. Here, layer-by-layer (LbL) self-assembly, which can be applied for biodegradable Mg alloys due to its extensive choice of usable units, holds great promise among all the surface techniques. In this review, the mechanisms of the driving force (i.e., electrostatic interaction, hydrogen bonding, charge transfer interaction and covalent bonding), cutting-edge advances in preparation methods (e.g., dipping, spraying, and spinning) and the functional properties (corrosion resistance, antibacterial activity, and biocompatibility) that could be achieved by the LbL coatings are summarized. A reasonable trend of the potential development of LbL for bio-Mg alloys is also proposed at the end of this article.

Metal organic frameworks (MOFs) are a new type of porous materials with some unique characteristics such as uniform pore size, adjustable pore structure, easy synthesis and structural diversity. Ionic liquids-modified MOFs (ILs/MOFs) composite materials not only retain the structural characteristics of MOFs, but also have the advantages of adjustable physical and chemical properties of ILs with high stability. They have great application potential in the field of separation and analysis, which has aroused great interest of researchers. This article mainly reviews the preparation methods of ILs/MOFs composite materials and their research progress in separation and analysis in the latest five years, including adsorption/extraction, chromatographic separation, spectral and electrochemical analysis. And their future development trends are expected.

To solve many-objective flow-shop scheduling problems (FSP), a genetic algorithm based on the relative entropy of fuzzy sets (REFS_GA) is proposed. A mathematical model of the many-objective FSP is...

Six new compounds, hyperpatulones A–F (1–6), along with ten additional known related derivatives (7–16), were isolated from Hypericum patulum (Guttiferae). Their structures were elucidated by extensive analysis of spectroscopic data (IR, UV, HRESIMS, 1D and 2D NMR), X-ray crystallography, electronic circular dichroism (ECD) spectroscopy and Rh2(OCOCF3)4-induced ECD. All compounds were tested for their cytotoxic activities on human HepG-2, HeLa, MCF-7, and A549 cell lines via 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Compound 5 exhibited significant cytotoxicities against HepG-2, HeLa and A549 cell lines with IC50 values of 9.52 ± 0.27, 11.87 ± 0.22 and 12.63 ± 0.12 μM, respectively.

Two new oleanane-type triterpenoids (1–2), a new ursane-type triterpenoid (3), and a new podocarpane-type diterpenoid (4), together with 20 known compounds (5–24) were isolated from the stems of Celastrus hindsii Benth. Their structures were identified on the basis of the spectral data (HRESIMS, IR, UV, 1D, and 2D NMR) and the absolute configurations were determined by comparison of experimental and calculated ECD data. The structures of 1 and 4 were further confirmed by single crystal X-ray diffraction analysis. In addition, all compounds were evaluated for their in vitro antiviral activities against respiratory syncytium virus (RSV) using cytopathic effect (CPE) reduction assay. Compounds 7, 10, 11, 19 and 24 exhibited obvious anti-RSV activity with IC50 values from 1.55 to 6.25 μM.

In this paper, grey and entropy parallel analysis (GEPA) is presented as a new fitness-assignment strategy for solving multi-objective optimization problems. An evolutionary algorithm based on GEPA is proposed, and the grey and entropy parallel relational grade (GEPRG) is used as the fitness value to guide the development of the evolutionary algorithm. Under the analysis of the existing research work, the multi-objective flow shop scheduling problem is chosen as the application object and a flow shop scheduling model with five objectives is established. GEPA_GA, the GA based on GEPA, is described. To verify the performance of the proposed algorithm, GEPA_GA, together with the GA based on the random weighting method (RW_GA), NSGA-II and the GA based on g-dominance (g_GA), are used to optimize the multi-objective flow shop scheduling problem. The experimental data are analyzed by the statistical analysis method, the Kruskal–Wallis test, and three evaluation metrics. The influences of the five grey relational operators and the distinguishing coefficient on the algorithm performance are also studied. Experiments shows that the results obtained by GEPA_GA are better than those of RW_GA, NSGA-II and g_GA even under the situation that the combination of operator and distinguishing coefficient is not the best. It is proven that GEPA_GA works well in solving the multi-objective flow shop scheduling optimization problem, and GEPA is a promising strategy for solving multi-objective optimization problems.

A new sesquiterpene (1) and a new natural product, β-triketone-based derivative (2), along with five known compounds (3–7) were isolated from the leaves of Rhodomyrtus tomentosa. Their structures w...

This paper addresses a flexible flow shop scheduling problem considering limited buffers and step-deteriorating jobs, where there are multiple non-identical parallel machines. A mixed integer programming model is proposed, with the criterion of minimizing the makespan and total tardiness simultaneously. To handle this problem, an effective hybrid meta-heuristic algorithm, named GVNSA, is developed based on genetic algorithm (GA), variable neighborhood search (VNS) and simulated annealing (SA). In the algorithm, with a two-dimensional matrix encoding scheme, the NEH (Nawaz–Enscore–Ham) heuristic and bottleneck elimination method are implemented to determine the initial population. A three-level rolling translation approach is designed for decoding. To balance the exploration and exploitation abilities, three effective steps are executed: 1) partial matching crossover and mutation strategy based on multiple neighborhood search structures are imposed on the GA operators; 2) a VNS with SA is introduced to re-optimize some individuals from GA, where four neighborhood structures are constructed; 3) a modified CDS (Campbell–Dudek–Smith) heuristic is embedded to disturb population in the mid-iteration. Numerical experiments are carried out on test problems with different scales. Computational results demonstrate that the proposed GVNSA can obtain higher quality solutions in comparison with other heuristics and meta-heuristics existing in literature.

A new β-carboline alkaloid (1) and two new matrine-type alkaloids (2 and 3), together with two known alkaloids (4 and 5), were isolated from the roots of Sophora tonkinensis. The new structures were elucidated via extensive analyses of the spectroscopic data (IR, UV, HRESIMS, NMR) and X-ray crystallography. The absolute configuration of 1 was established by electronic circular dichroism data. Herein, is the first report of β-carboline alkaloid in the plant of genus Sophora. In addition, the cytotoxic activities against HepG2 cells of compounds 1–5 were evaluated using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. Among them, compounds 1, 4 and 5 showed a weak cytotoxic activity with IC50 values of 87.4 ± 7.1, 91.8 ± 3.5 and 48.9 ± 5.2 μM, respectively.

Six new compounds, hyperpatulones A-F (1-6), along with ten additional known related derivatives (7-16), were isolated from

A benzyl functionalized ionic liquid, 1-benzyl-3-methylimidazolium bis [(trifluoromethyl) sulfonyl] imide ([BeMIM][Tf 2 N]), was synthesized and used as an extraction solvent of dispersive liquid-liquid microextraction (DLLME) for enrichment and determination of 5 kinds of organophosphorus pesticides (phoxim, fenitrothion, chlorpyrifos, phorate and parathion) and 2 kinds of aromatic compounds (chloronaphthalene and anthracene) in environmental water samples by high-performance liquid chromatography (HPLC). [BeMIM][Tf 2 N] had higher extraction efficiency than 1-octyl-3-methylimidazolium bis [(trifluoromethyl)sulfonyl] imide and common organic solvents such as carbon tetrachloride and tetrachloroethylene. The extraction was performed using 40 μL of [BeMIM][Tf 2 N] as respective extraction solvent and 1 mL of methanol as dispersive solvent with centrifugal time of 5 min. Under the optimal conditions, the proposed method exhibited a good linearity for all analytes with correlation coefficients of 0.9994−0.9998. The precision, described as intra-day and inter-day relative standard deviations (RSDs) of five replicate experiments at three different concentrations of 10, 40 and 100 μg L −1 , was 1.1%–4.3% and 0.8%–4.8%, respectively. The limits of detection (LODs) were 0.01–1.0 µg L −1 ( S/N = 3). The developed method was convenient, rapid and applicable to detection of the analytes in real environmental water samples with satisfactory recovery of 82.7%–118.3% and RSDs of 0.7%–5.6%. Introduction of benzyl group into the imidazolium could considerably elevate the extraction efficiecny of the analytes due to enhanced π-π interaction between [BeMIM][Tf 2 N] and analytes. [BeMIM][Tf 2 N] was a satisfactory extraction solvent with a high enrichment factor of 339 and extraction efficiency of 81.4%. The partition coefficients of all analytes in [BeMIM][Tf 2 N]-DLLME system were determined and the extraction mechanism was discussed.

To reduce the bacteria-associated infection for the Ti implant, an antibacterial coating composed of gentamicin (GS) and polyacrylic acid (PAA) was constructed using layer-by-layer (LbL) assembly technique. The surface morphology and chemical composition of the obtained multilayers were characterized by atomic force microscopy (AFM), scanning electron microscopy (SEM), fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS). The plate counting method was employed to evaluate the antibacterial activity against Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli) of the coating. The results revealed that the drug loaded multilayers could inhibit the growth of bacteria on the Ti substrate.

Eight new matrine-type alkaloids, flavesines G-J (1-4), alopecurine B (5), 7,11-dehydro-oxymatrine (6), 10-oxy-5,6-dehydromatrine (7), and 10-oxysophoridine (8), along with nine known analogues (9-17) were isolated from the roots of Sophora flavescens. Compounds 1-3 are the first natural matrine-type alkaloids with an open-loop ring D, while compound 4 represents an unprecedented dimerization pattern constructed from matrine and piperidine, and 5 is the first example of a matrine-type alkaloid with cleavage of the C-5-C-6 bond. The new structures were elucidated by means of spectroscopic data analysis (including NMR, MS, IR, and UV), and the absolute configurations were determined using single-crystal X-ray diffraction and ECD data. The isolated alkaloids were evaluated for their antiviral activity against hepatitis B virus, and compounds 1, 4, 5, 10, and 14 exhibited comparable antiviral potencies to matrine.

This work presents a novel nondestructive cavity pressure characterization approach in microinjection molding (μIM) through measuring 3D part thickness distributions. For this purpose, a plano lens was designed and experiments based on Taguchi method were conducted. Both overall and local lens thickness distributions under various process conditions were analyzed in terms of their relevance with the cavity pressure during molding. Unexpectedly, a reliable linear regression model was developed fulfilling nondestructive multi-point or even continuous cavity pressure characterization with the overall lens thickness distribution. Furthermore, the topography of the constructed 3D thickness surface was found to depend on both process condition and measuring position. Finally, the process conditions were optimized for obtaining uniform distributions of both 3D thickness and cavity pressure.

Although co-infection of tuberculosis (TB) and intestinal parasites, including protozoa and helminths, in humans has been widely studied globally, very little of this phenomenon is known in China. Therefore, a cross-sectional study was conducted in a rural county of China to investigate such co-infections. Patients with pulmonary TB (PTB) undergoing anti-Mycobacterium tuberculosis (anti-MTB) treatment were surveyed by questionnaires, and their feces and blood specimens were collected for detection of intestinal protozoa and helminths, routine blood examination and HIV detection. The χ(2) test and multivariate logistic regression model were used to identify risk factors. A total of 369 patients with PTB were included and all of them were HIV negative. Overall, only 7.3% of participants were infected with intestinal protozoa, among which prevalence of Blastocystis hominis, Entamoeba spp. and Trichomonas hominis were 6.0%, 1.1% and 0.3%, respectively; 7.0% were infected with intestinal helminths, among which prevalence of hookworm, Trichuris trichiura, Ascaris lumbricoides and Clonorchis sinensis were 4.3%, 1.9%, 0.5% and 0.3%, respectively; and 0.5% were simultaneously infected with intestinal protozoa and helminths. Among patients with PTB, body mass index (BMI)≤18 (OR=3.30, 95% CI=1.44-7.54) and raised poultry or livestock (e.g., chicken, duck, pig) (OR=3.96, 95% CI=1.32-11.89) were significantly associated with harboring intestinal protozoan infection, while BMI≤18 (OR=3.32, 95% CI=1.39-7.91), anemia (OR=3.40, 95% CI=1.44-8.02) and laboring barefoot in farmlands (OR=4.54, 95% CI=1.88-10.92) were significantly associated with having intestinal helminth infection. Additionally, there was no significant relationship between duration of anti-MTB treatment and infection rates of intestinal parasites including protozoa and helminths. Therefore, preventing malnutrition, avoiding unprotected contact with reservoirs of protozoa, and improving health education for good hygiene habits, particularly wearing shoes while outdoors, are beneficial in the prevention of intestinal protozoan and helminth infection among patients with PTB.

The MgO thin films are deposited at various inclined angles. The morphology investigated by scanning electron microscope (SEM) shows the MgO thin films deposited at high inclined angles have columnar grain. The relationships between full width high maximum (FWHM) of ω-scan, residual stresses and the inclined angles are studied. The results show the smallest FWHM of MgO (002) is 4.968°, the residual stress of MgO thin films is compressive stress, and the residual stress of MgO thin films deposited at the inclined angle of 55° is the smallest. So the microstructures of MgO thin films fabricated by the oblique angle deposition (OAD) technique effectively control the residual stresses.

A Y zeolite-containing wide-pore composite was synthesized by in situ technique using polyvinyl alcohol and silica sol material. A fluid catalytic cracking (FCC) catalyst for maximizing gasoline yield was successfully developed with the modified composition. The as-made zeolite Y in its sodium form had a relative crystallinity of 52.9 % with a high silica/alumina amount of substance ratio of 5.7. The FTIR analysis showed that the acid distribution of the catalyst modified with rare earth, phosphorus and steaming stabilization process was more concentrated on the range of intermediate and strong acidity. This kind of modification can direct more hydrocarbons to enter into the pores to be converted, as well as remarkably increases the possibility of gasoline formation through a cracking reaction. The nitrogen adsorption–desorption analysis showed that the catalyst had more meso- and macro-pores distribution, which can effectively reduce the mass-transfer resistance in the reaction process and accelerate the diffusion of the product molecules. The evaluated results indicated that the prepared catalyst could decrease the excessive cracking of middle distillate and improve the gasoline yield effectively. The gasoline yield by mass had increased by 2.69 %, while the coke yield and dry gas yield had decreased by 0.91 % and 0.19 %, respectively, and then the olefin content by volume in the cracked gasoline reduced by 4.6 %, the research octane number (RON) and motor octane number (MON) increased by 0.6 and 0.5, respectively. The good product selectivity and higher gasoline yields of the prepared catalyst were obviously related to its wide pore structure and its optimized acidity distribution. This work is licensed under a Creative Commons Attribution 4.0 International License., Zeolit Y velikih pora sintetiziran je in situ upotrebom polivinilnog alkohola i sola silicijeva dioksida. Za krekiranje u fluidiziranom sloju (FCC) razvijen je katalizator promijenjena sastava. Zeolit Y u natrijskom obliku imao je relativnu kristalnost 52,9 % i visoki množinski omjer SiO2/Al2O3 5,7. Katalizator s elementima rijetkih zemalja, fosforom i stabiliziran izlaganjem pari, prema analizi FTIR-om, imao je više aktivnih mjesta srednje i jake kiselosti. S takvim preinačavanjem katalizatora više ugljikovodika ulazi u pore i povećava se proizvodnja benzina krekiranjem. Analiza adsorpcijom i desorpcijom dušika pokazuje da katalizator ima više mezo- i makropora što može olakšati prijenos materijala i ubrzati difuziju molekula produkata. Rezultati pokazuju da bi pripravljeni katalizator mogao smanjiti pretjerano krekiranje srednjeg destilata i povećati iskorištenje s obzirom na benzin. Iskorištenje benzina po masi povećalo se za 2,69 %, a iskorištenje koksa i suhog plina smanjilo za 0,91 i 0,19 %. Obujamski udjel olefina u benzinu smanjio se za 4,6 % dok su istraživački oktanski broj (RON) i motorni oktanski broj porasli za 0,6 i 0,5. Dobra selektivnost s obzirom na produkte i visoka iskorištenja benzina u katalizi s pripravljenim katalizatorom očito su povezana sa širokoporoznom strukturom i optimiranom distribucijom kiselosti. Ovo djelo je dano na korištenje pod licencom Creative Commons Imenovanje 4.0 međunarodna.

Density-functional theory (DFT) has been used to calculate the interaction of nitric oxide with 3d metal dimers (scandium through zinc) and determine the ground-state geometrical configurations and vibrational frequencies. Results are compared to the relevant experimental values and to other theoretical investigations when available, and the overall agreement has been obtained. On going from left to right side of the Periodic Table, the preference for the coordination mode of NO to transition-metal dimers is from side-on-bonded mode (Sc, Ti, V), via semibridging (Cr), to end-on-bonded mode (Mn, Fe, Co, Ni, Cu). The N-O stretching vibrational frequencies in the ground states of M2NO (M = Sc to Zn) increase generally from the left to the right side of the Periodic Table, whereas the N-O bond lengths decrease generally. The binding energies exhibit an overall decrease trend. These general trends in the interaction of nitric oxide with 3d metal dimers mirror the main features of NO adsorption on transition metal surfaces.

The main characteristics of a surface are physical and chemical structure, surface tension and surface roughness. Surface roughness is one of the critical factors, which could cause instability in quality performance. In this paper, surface roughness of alumina thin films deposited on a silicon substrate by using electron beam evaporation with oblique angle deposition were studied. It has been found that the surface roughness of the alumina thin films was dependent on the substrate temperature, the deposition rate, the film thickness and the inclined angle. The experimental results showed that increasing the substrate temperature reduced the surface roughness at a low inclined angle and enhanced the surface roughness at a high inclined angle, and the surface roughness increased with increasing deposition rate and film thickness. By choosing the appropriate film preparation parameters, the film surface roughness was effectively controlled.

A study of depositing high quality c-axis oriented polycrystalline aluminum nitride thin film at room temperature was presented. Aluminum nitride films were grown by mid-frequency (MF) reactive sputtering. Metallic aluminum target was used to deposit AlN films in Ar/N2 gas mixture. A 50nm thick of N-rich AlN buffer layer was deposited at the initial stage of sputtering process to improve the film quality. The composition, preferred orientation and residual stress of the films were analyzed by EDS, XRD and Raman microscope, respectively. The results showed that the N-rich AlN buffer layer improved the textured degree and reduced the residual stress significantly of the AlN thin films. The near stoichiometric AlN thin film with highly textured degree was obtained. The FWHM value of the rocking curve for (0002) diffraction peak was about 1.6°, and the residual tensile stress was about 500MPa. The piezoelectric d33 coefficient increased with the decreasing of FWHM value, and the highest d33 coefficient of 3.6 pF/C was obtained.

The electrical and morphological properties of magnesium oxide (MgO)/alumina (Al 2 O 3 ) bilayered thin films prepared by electron beam evaporation at oblique incidence are reported. The MgO thin films are deposited when the incline angle is 55° on various Al 2 O 3 thin films incline angles. A columnar grain with a roofing-tile-shaped surface is observed in these MgO/Al 2 O 3 thin films. X-ray pole figures and θ-2θ scan, ω-scan are used to characterize in-plane and out-of-plane textures. The relationships between ω-FWHM, capacitor, leakage current, and the inclined angles are studied. The morphology is investigated by using scanning electron microscope (SEM). So the oblique angle deposition method is an effective way to control the microstructure of thin films.

Epidemiologic studies of co-infection with tuberculosis (TB) and intestinal parasites in humans have not been extensively investigated in China. A cross-section study was conducted in a rural county of Henan Province, China. Pulmonary TB (PTB) case-patients receiving treatment for infection with Mycobacterium tuberculosis and healthy controls matched for geographic area, age, and sex were surveyed by using questionnaires. Fecal and blood specimens were collected for detection of intestinal parasites, routine blood examination, and infection with human immunodeficiency virus. The chi-square test was used for univariate analysis and multivariate logistic regression models were used to adjust for potential confounding factors. A total of 369 persons with PTB and 366 healthy controls were included; all participants were negative for human immunodeficiency virus. The overall prevalence of intestinal parasites in persons with PTB was 14.9%, including intestinal protozoa (7.9%) and helminthes (7.6%). The infection spectrum of intestinal parasites was Entamoeba spp. (1.4%), Blastocystis hominis (6.2%), Trichomonas hominis (0.3%), Clonorchis sinensis (0.3%), Ascaris lumbricoides (0.5%), Trichuris trichiura (2.2%), and hookworm (4.6%). The prevalence of intestinal parasites showed no significant difference between persons with PTB and healthy controls after adjusting for potential confounding factors. There was no factor that affected infection rates for intestinal parasites between the two groups. Infection with intestinal parasites of persons with PTB was associated with female sex (adjusted odds ratio [AOR] = 2.05, 95% confidence interval [CI] = 1.01–4.17), body mass index ≤ 19 (AOR = 3.02, 95% CI = 1.47–6.20), and anemia (AOR = 2.43, 95% CI = 1.17–5.03). Infection of healthy controls was only associated with an annual labor time in farmlands > 2 months (AOR = 4.50, 95% CI = 2.03–10.00). In addition, there was no significant trend between rates of infection with intestinal parasites and duration of receiving treatment for infection with M. tuberculosis in persons with PTB. The prevalence of intestinal parasites was not higher in persons with PTB, and there was no evidence that PTB increased susceptibility to intestinal parasites in this study. However, for patients with PTB, women and patients with comorbidities were more likely to be infected with intestinal parasites.

Two new quinolizidine-based alkaloids (2 and 12), along with ten known ones (1, 3-11) were isolated from the roots of S. tonkinensis. Their structures were determined by spectroscopic data (including NMR, MS, IR, and UV), X-ray single crystal diffraction, electronic circular dichroism analyses (ECD), and comparing with related literatures. Compounds 1, 3-12 at non-toxic concentrations exhibited potent anti-inflammatory activities according to in vitro and in vivo anti-inflammatory tests. Among them, (-)-anagyrine (4), sophocarpine (8), 14β-hydroxymatrine (10), and 7β-sophoramine (12) showed more potent in vitro anti-inflammatory activities, and 5α,14β-dihydroxymatrine (2), (-)-anagyrine (4), sophocarpine (8), and 5α-hydroxymatrine (9) exhibited better in vivo anti-inflammatory effects.

Whether the design of new structure or reinforcement of the existing projects, structure earthquakereduction design is always the focus of research at home and abroad. The buckling restrained braces won the unanimous endorsement of the engineering sector with good energy dissipation capacity and simpleeasy construction process. This Paper based on the ANSYS analysis the structural response through simulated the bucklingrestrained brace frame structure and the general reinforced concrete frame on effect of the rare earthquake or design earthquake, and analysis the bucklingrestrained braces on the seismic performance of reinforced concrete frame structure. The analysis results show that the seismic performance of reinforced concrete frame with bucklingrestrained braces well, it can effectively reduce the maximum story drift and control structural damage. Therefore, Bucklingrestrained Brace should be used extensively to reinforced concrete framework .

To investigate the association between metabolic syndrome (MetS) and the National Institutes of Health-Chronic Prostatitis Symptom Index (NIH-CPSI) in a population-based sample of Chinese men.From October 2010 to July 2011, 1896 men, aged between 20 and 50 years, residing in Shijingshan district of Beijing, China, were selected to participate in the Male Reproductive Health Program (a random cross-sectional survey). The Chinese version of the NIH-CPSI questionnaire was used to identify men with prostatitis-like symptoms. The presence of MetS was determined according to the 2005 National Cholesterol Education Program-Adult Treatment Panel III criteria for Asian Americans.Complete data were available for 1673 men. The major domains of NIH-CPSI scores were significantly different among different body mass index (BMI) groups (P.05). No significant differences were identified in the incidence of prostatitis-like symptoms or each NIH-CPSI scores between patients with MetS and those without MetS. When the age and BMI were adjusted, there was no significant correlation between the components of MetS and each NIH-CPSI scores.There was no significant correlation between MetS or components of MetS and chronic prostatitis/chronic pelvic pain syndrome. Age and BMI were identified as a risk factor for chronic prostatitis/chronic pelvic pain syndrome. Further studies are necessary to confirm our results.

In this paper, we report on the preparation and characterization of polyimide (PI) thin films through vapor deposition polymerization (VDP). PI thin films were formed by vapour co-deposition of the precursor monomers pyromellitic dianhydride (PMDA) and 4,4-oxydianiline (ODA) following a thermal treatment at a temperature of over 300°C. The effects of the polymerization temperature on the characterization of PI films were investigated using scanning electron microscopy and Fourier transform infrared spectroscopy. The results showed that the deposited polyamic acid (PAA, a precursor of polyimide) with imidization in the temperature interval of 300-400°C are smooth, uniformly thick and form without shrinkage.

A physics model was established for describing the particle size distribution of beryllium (Be) powder produced by impact attrition milling. In this model, two factors were considered: the first, the distribution of existing state of particles with different original kinetic energy should obey the Maxwell-Boltzmann statistics after impacted, it was that, being at higher energy level made big particles unstable, which were easy to be fractured into smaller pieces in impact attrition process, this influencing factor described as the negative exponential of particles size; the second, the tendency to remain low surface energy needed particles should keep big volume as much as possible, this effect defined as the cube of particles size. The actual particle size distribution of Be powder was resulted from the competition between these two factors. Calculating result from the model was in good agreement with data from measurement.

A balloon filled with electron gas model was built to simulate metal for calculating its bulk elastic. Electron gas obeyed Fermi-Dirac distribution and satisfied with theory of ideal gas. Expression of metal bulk elastic modulus was derived, and the comparison between the new method given in this paper with current method according to theory of atom potential energy on calculation accuracy was also given. It showed that, pressure of electron gas closely related to bulk elastic modulus, and maybe it was the major factor in determining bulk elastic modulus of metal; not all of valence electrons of atom in metal became conduction electrons to form the electron gas; new model of present work is superior to traditional method based on calculating derivative of potential energy.

Most thyroid lymphomas are B-lineage, and T-cell lymphomas are rare. None of primary thyroid extranasal NK/T-cell lymphoma (NKTCL) has been reported in the literature. Here, we report a case of extranasal NKTCL exclusively arising in the thyroid in an 18-year-old Chinese. The patient presented with rapid anterior swelling at the neck and aggravated dyspnea for 2 months. Neck computer tomography scan revealed diffuse thyroid enlargement in the left lobe compressing the trachea. The thyroid function test was indicative of hypothyroidism. Gastroscopy demonstrated chronic nonspecific gastritis. Subtotal thyroidectomy was performed. Histological examination showed a diffuse infiltration of neoplastic lymphoid cells with an angiodestructive behavior. Immunophenotype is positive for CD2, CD56, CD43, and TIA-1, and typically negative for surface CD3. Epstein-Barr virus-encoded small RNAs were detected in tumor cells. A diagnose of primary thyroid extranasal NKTCL-N lymphoma was confirmed by the findings. The patient was treated with CHOP-L combination chemotherapy followed by local radiotherapy, and tolerated the modality well. The patient has been in remission for 28 months so far. To our knowledge, this is the first case report of primary extranasal NKTCL exclusively arising in the thyroid. The case has a relatively good treatment outcome with timely diagnosis and multimodality approach.

A novel utilization method of filter residue from the preparation process of zeolite-based catalysts was investigated. Y zeolite and a fluid catalytic cracking (FCC) catalyst were synthesized from filter residue. Compared to the Y zeolite synthesized by the conventional method, the Y zeolite synthesized from filter residue exhibited better thermal stability. The catalyst possessed wide-pore distribution. In addition, the pore volume, specific surface area, attrition resistance were superior to those of the reference catalyst. The yields of gasoline and light oil increased by 1.93 and 1.48 %, respectively. At the same time, the coke yield decreased by 0.41 %. The catalyst exhibited better gasoline and coke selectivity. The quality of the cracked gasoline had been improved., Proučena je upotreba taloga preostalog nakon priprave katalizatora baziranog na zeolitima. Od taloga su pripravljeni zeolit Y i katalizator za katalitičko krekiranje u fluidiziranom sloju (FCC). Ovako sintetiziran zeolit Y termički je stabilniji u odnosu na zeolit Y sintetiziran konvencionalnom metodom. Katalizator ima široku distribuciju veličine pora. U odnosu na referentni katalizator pokazuje veći obujam pora i specifičnu površinu te bolju otpornost na atriciju. Iskorištenje benzina i lakog ulja povećalo se za 1,93 i 1,48 %, a koksa smanjilo za 0,41 %. Katalizator je pokazao bolju selektivnost s obzirom na benzin i koks, a poboljšala se kvaliteta krekiranog benzina.

A numerical analysis was performed to investigate the temperature distribution and thermal stress field in monocrystal silicon rod in the cooling process of manufactured with Czochralski (CZ) method. The thermally-induced residual stress fields of silicon rod under different length of cool-down time conditions were obtained as well as temperature fields, respectively. All simulations were finished by using ANSYS finite element code. It showed that, maximum thermal stress was mainly appeared on rod surface, the influence of length of cool-down time on it was not remarkable, the magnitude of it was far below the critical strength of silicon throughout.

Based on the analysis of damping theory of Thyristor Controlled Series Capacitor (TCSC), the influence of TCSC to electric magnetic torque with and without damping function is studied by one generator infinite model so to deduce the mechanism of low frequency oscillation damping of TCSC. Combined with ‘the Twelfth Five-year Plan’ power and transmission grid construction plan in western Yunnan, the proper scheme for TCSC damping control was chosen in the southwestern Yunnan power grid and the transient and dynamic simulations of southwestern Yunnan power grid were performed. The simulation results show that TCSC can improve the system damping when the grid is in Yunguang area oscillation mode with frequency of 0.27Hz and 0.6Hz，especially in condition when Yunnan grid is in the local area oscillation mode of 0.6 Hz. The simulations also demonstrate that TCSC can improve transient stability of Yunnan power grid. The application of TCSC in southwestern Yunnan Power Grid is of great significance to power grid safe operation.

The leaf spring is a representative type of laminated structure. Based on the linear theories of curve beams, the first derivatives of the leave’s status-vector of the leaf spring are provided. The first derivatives of the combination status-vector are obtained by properly dealing with the nonlinear interacted forces between adjacent leaves. Moreover, the precise integration technology and the transform matrix method are introduced to solve the equations. The force-displacement curve of a leaf spring is then calculated separately by using the present method and the finite element software ANSYS. From the results, the precision and advantages of the present methods for analyzing the leaf spring are revealed. The Coulomb’s damping ratio of the leaf spring is studied by using the present method.

Study on the characteristics of tensile bond strength in concrete interfacial transition zone. Calculate the tensile bond strength of interfacial transition zone in concrete by the way of vertical drawing cobblestones of different grain size from C30 concrete by MTS hydraulic loading system .(the grain size include 50,70,90,100mm) results show that:1.when the cobblestones diameter is in a certain range(

For polycrystalline Beryllium (Be) specimens, data of yield strength, ultimate strength, elastic modulus, inelastic secant modulus elongation and grain size were obtained by using of material testing machine and metaloscope. It showed that: elastic modulus, inelastic secant modulus were basically independent with grain size; ultimate strength appeared at the end of tension process; relation between rate of yield strength to ultimate strength and elongation was found to be linear, but this rate had no clear correlation with grain size; relation between strength (yield, ultimate) and grain size was satisfied with Hall-Petch equation. Based on test data and analysis above, a bilinear model was given to simulate stress-strain constitutive behavior; an equation expressing relation between elongation and grain size was also derived.

A numerical analysis was performed to investigate the thermally-induced residual stress caused by the thermal expansion mismatch between Be and BeO. Models were constructed according to the real situation that the BeO particles embedded in grains or distributed at the grain boundaries, where the temperature-dependent materials properties, particle volume fraction and size and interparticle distance were taken into account. In simulation, it supposes particles inside grain no interacting with others, particles along the grain boundary being a period distribution. Be is modeled as elastic and elastic-plastic material with bilinear kinematic hardening model. BeO is modeled as isotropic and linear elastic. All simulations are performed by using ANSYS finite element code. Results show that the size, location and the volume fraction of particles influence on the residual stress (strain) to different extent during cooling process.

XPS analysis is used in studying surface chemical composition and structure of ultrafine raw Al powder and PVP/Al composite powder, respectively. It shows that: in PVP/Al composite powder’s surface, comparing with raw Al powder, relative content of Al decrease and relative contents of C and N increase. New chemical bonds are formed in PVP/Al composite powder’s surface, and it is certain that, these new chemical bonds derive from N atom and O atom of PVP’s pyrrole with Al atom in Al powder surface.

Children scooter safety performance is not good enough in the market, the cause of the majority of injuries to children is difficult to control the speed or emergency braking. According to the phenomenon, this paper focuses on designing dynamic scooter brake device for 8-10 child, we conceive that the brake device is given the force of the rolling friction and the sliding friction, so it can play a dual brake effect. It will enhance the security and stability of children dynamic scooter.

The dynamic compaction (DC) method is a versatile ground treatment technique with growing popularity. It is applicable to a wide variety of soil types and conditions, particularly sandy materials and granular fills. This study presents a case history of the dynamic compaction with a high energy level of 6,000 kN·m on granular deposits at a site in China. The reclaimed site featured loose backfill with heterogeneity and saturated silt. In order to properly deal with such soil conditions and to optimize the DC design, field tests were conducted to determine the influencing factors in DC. Deformation tests were performed to ascertain the rational spacing of impacts and the optimal number of drops and to provide proofs to the adjustment of the original DC procedure. Monitoring of the pore water pressure helped obtain the time delay between passes. The approach to assess the depth of improvement was discussed based on interpretations of the spectral analysis of surface waves (SASW) test. Analysis of the SASW and plate-load tests demonstrated significant improvement in the soils at the site, with no obvious weak layers. Following dynamic compaction, the allowable ground-bearing capacity and the depth of improvement at the site were no less than 270 kPa and 7.4 m, respectively.

Oracle is a database management system supporting the object-oriented data model that is usually adopted by the storage technology of persistent object. This paper describes the main features and characteristics that an object-oriented database system must have to qualify as an object-oriented data model. The paper introduces how to describe and implement the main modeling elements of the object-oriented data model in Oracle database which are the main components of class diagram, including the class, attribute, method, inheritance and polymerization. The examples of SQL that the paper offers can successfully run in Oracle 10g.

Optically active films were built up from poly(allylamine hydrochloride) (PAH) and R-(+)--phenylethylamine derivatives of poly(ethylene-alt-maleic acid) (PEMA-PEA) with substituting degrees (DS) ranging from 0.48 to 0.97. The growth of the film was monitored with the circular dichroism (CD) and the UV spectrophotometer and the effect of DS of PEMA-PEA on the film was investigated. UV and CD data show the growth regime of the multilayer changing from exponential to linear. Deposition amounts of PEMA-PEA in multilayer films decrease with the increase in DS of PEMA-PEA, which was explained based on the conformation of the polyelectrolyte and the charge overcompensation as the polyelectrolyte was deposited on the surface of the film. These results are of benefit to the development of multilayer films for the chiral separation of enantiomers.

Recycled PET is an important resource of waste, which reused with polar or crystallization polymers, such as PC, PA and PE, by melting blend method have been well studied. But the study of rPET blend with nonpolar and amorphous polymer is still inadequate. In the present work, nano-SiO2 particles were introduced to recycled PET/ABS/AES (55/40/5) blends by extrusion processing. It has been investigated how nano-SiO2 particles influences the morphology and mechanical properties of rPET/ABS blends by the use of AES as compatibilizer. It showed a uniform dispersion of the nano-SiO2 components, and the two-continuous phase of rPET/ABS was more evenly when the content of nano-SiO2 particles at a low level. The tensile strength and beam impact strength of rPET/ABS/AES blends were increased at the same time by adding nano-SiO2 particles..

High energy dynamic compaction (HEDC) is adopted in a coastal reclamation area because the grain size of backfilled soil mostly ranges between 20 cm and 100 cm. The in situ tests for evaluating the effectiveness of HEDC were performed on the backfilled soil ground. The crater depth per drop and the whole test zone elevations before and after HEDC were measured and analyzed. Dynamic penetration tests and spectral analysis of surface wave (SASW) tests were used for investigating the improvement depth. Furthermore, the allowable bearing capacity of HEDC treated ground was determined based on the results of plate-load tests. It was found that HEDC did not cause the ground surface heave during construction, and was more effective than low energy dynamic compaction (LEDC) in terms of applied energy utilization. Based on the test results, the improvement depth of HEDC at this site was not less than 14 m, and there was no obvious weak layer within the range of improvement depth. The allowable bearing capacities w...

The paper reports a study into the dynamic compaction of very coarse grained material placed over soft clays in a coastal reclamation area. It was found that higher energy levels are more effective than low impact energy levels, which can result in ground heave between impact points. Spectral analysis of surface wave (SASW) tests and plate load tests confirmed the effect of the dynamic compaction extended to at least 10 m, with no obvious weak layers identified. Following dynamic compaction, the allowable bearing capacity was >120 kPa.