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61.
Pomegranate (Punica granatum L.) has been cultivated from ancient times for its economic, ornamental and medicinal properties globally. Here, we report the isolation and characterization of 12 polymorphic microsatellite markers from a repeat-enriched genomic library of Punica granatum L. The genetic diversity of these loci was assessed in 60 genotypes of Punica granatum L. All loci were variable: the number of polymorphic alleles per locus ranged from two to five (average 2.9). The observed and expected heterozygosities ranged from 0.15 to 0.87 and 0.29 to 0.65, respectively. The polymorphic information content ranged from 0.26 to 0.61 (average: 0.43). To the best of our knowledge, this is the first time that polymorphic microsatellite markers have been reported for P. granatum L. These new markers should allow studies of the population structure and genetic diversity of pomegranate to be performed in the future.  相似文献   
62.
In this work we conducted classical molecular dynamics (MD) simulation to investigate the mechanical characteristics and failure mechanism of hexagonal boron-nitride (h-BN) nanosheets. Pristine and defective structure of h-BN nanosheets were considered under the uniaxial tensile loadings at various temperatures. The defective structure contains three types of the most common initial defects in engineering materials that are known as cracks, notches (with various length/size), and point vacancy defects (with a wide range of concentration). MD simulation results demonstrate a high load-bearing capacity of extremely defective (amorphized) h-BN nanosheets. Our results also reveal that the tensile strength decline by increasing the defect content and temperature as well. Our MD results provide a comprehensive and useful vision concerning the mechanical properties of h-BN nanosheets with/without defects, which is very critical for the designing of nanodevices exploiting the exceptional physics of h-BN.  相似文献   
63.
In this paper, the three-dimensional large frictional contact deformation of powder forming process is modeled using a node-to-surface contact algorithm based on the penalty and augmented-Lagrange approaches. The technique is applied by imposing the normal and tangential contact constraints and modifying the contact properties of frictional slip. The Coulomb friction law is employed to simulate the friction between the rigid punch and the work piece. It is shown that the augmented-Lagrange technique significantly improves imposing of the constraints on contact surfaces. In order to predict the non-uniform relative density and stress distributions during the large deformation of powder die-pressing, the nonlinear contact friction algorithm is employed within the framework of large finite element deformation, in which a double-surface cap plasticity model is used for highly nonlinear behavior of powder. Finally, the numerical schemes are examined for accuracy and efficiency in modeling of a set of powder components.  相似文献   
64.
Clean Technologies and Environmental Policy - One of the most essential methods for preserving water resources is water reuse. The present study has been aimed at adjusting a gray water treatment...  相似文献   
65.
In this study, we comparison of the antimicrobial activity on the nanosilver shapes; Ag-nanoplates (Ag-NPls), Ag-nanorods (Ag-NRds) and Ag-nanoparticles (Ag-NPs). Nanosilver shapes were prepared with a stabilizer, such as poly (N-vinyl-2-pyrrolidone) (PVP). Antimicrobial effect of nanosilver shapes for Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli) was investigated using disc diffusion and minimum inhibitory concentration (MIC) methods. The growth of Gram-positive (S. aureus) and Gram-negative (E. coli) bacteria were inhibited by nanosilver shapes. With BET technique, it was found that surface area of nanosilver shapes are key factor for controlling antimicrobial activity inside of the S. aureus and E. coli bacteria. Anti-bacterial activity of nanosilver shapes was found to be dependent on the shape and size of silver particles. Also, the Ag-NPls did show the best surface area and antimicrobial activity for the test organisms. The scanning electron microscopy (SEM), indicated that, the most strains of S. aureus and E. coli were damaged and extensively disappeared by addition of Ag-NPls.  相似文献   
66.
67.
Free-radical polymerization of polyethylene glycol methyl ether methacrylate macromer (PEGMEMA) was studied in aqueous media and in the presence of potassium persulfate (KPS) as water soluble initiator. An on-line nuclear magnetic resonance (NMR) method was applied to record the reaction data and determine the monomer conversion at various times during the polymerization reaction progress. 1H NMR spectrum of reaction mixture containing monomer, initiator and resultant polymer was continuously recorded in NMR instrument with the increase of reaction time. By processing the obtained data from NMR spectrum, the rate equation can be derived and reaction order can be determined with regard to monomer and initiator concentration. In other words, to determine the order of polymerization with regard to the concentration of reactants in free-radical polymerization of PEGMEMA, macromer samples with different amounts of monomer and KPS were prepared and polymerized at 50?°C. Orders of reaction with respect to monomer and initiator molar concentrations were equal to 1.025 and 0.480, respectively. The obtained values for reaction orders in this study were consistent with the classical kinetic rate equation in which the dependency of polymerization rate (R p) on monomer and initiator concentrations was equal to 1 and 0.5, respectively. To measure polymerization activation energy (E a), the effect of reaction temperature on the polymerization rate was investigated and E a?=?37.08?kJ/mol was obtained at the temperature range of 40?C50?°C.  相似文献   
68.
The appropriate production of liquefied natural gas(LNG)with least consuming energy and maximum efficiency is quite important.In this paper,LNG production cycle by means of APCI Process has been studied.Energy equilibrium equations and exergy equilibrium equations of each equipment in the APCI cycle were established.The equipments are described using rigorous thermodynamics and no significant simplification is assumed.Taken some operating parameters as key parameters,influences of these parameters on coefficient of performance(COP)and exergy efficiency of the cascading cycle were analyzed.The results indicate that COP and exergy efficiency will be improved with the increasing of the inlet pressure of MR(mixed refrigerant)compressors,the decreasing of the NG and MR after precooling process,outlet pressure of turbine,inlet temperature of MR compressor and NG temperature after cooling in main cryogenic heat exchanger(MCHE).The COP and exergy efficiency of the APCI cycle will be above 2% and 40%,respectively,after optimizing the key parameters.  相似文献   
69.
In this research, the influences of adding talc mineral particles of 10 μm particle size on the shrinkage and the mechanical properties of injection molded polypropylene (PP)/talc composites were investigated. PP has a crystalline molecular structure and hence it possesses nonisotropic shrinkage along and across the flow directions. Addition of the talc mineral filler to PP induced an isotropic shrinkage in the molded part because of the nonisotropic shape of talc particles. The results of experiments indicated that the maximum flexural strength, maximum impact strength, and isotropic shrinkage were achieved by adding 10, 20, and 30 by weight percent of talc respectively. By incorporating of 10 wt% of talc particles into the PP matrix, the tensile strength was hardly affected but the occurrence of cold drawing phenomena in the tensile test was hindered considerably. The flake‐shape structure of talc filler played an important role in determining the molded part shrinkage and mechanical properties. POLYM. ENG. SCI., 47:2124–2128, 2007. © 2007 Society of Plastics Engineers  相似文献   
70.
Chondrosarcoma is the second‐most malignant cancer of the bone and routine treatments such as chemotherapy and radiotherapy have not responded to the treatment of this cancer. Due to the resistance of chondrosarcoma to radiotherapy, the combination of therapeutic methods has been considered in recent years. In this study, a novel combination approach is used that allows photodynamic therapy to be activated by X‐rays. The synthesis of Mn‐doped zinc sulphide (ZnS) quantum dots was carried out and chlorin e6 photosensitiser attached by covalent and non‐covalent methods and their application as an intracellular light source for photodynamic activation was investigated. The toxicity of each nanoparticles was evaluated on chondrosarcoma cancer cells (SW1353) before and after radiation. Also, the effect nanoparticle‐photosensitiser conjugated type was investigated in the therapeutic efficacy. The characterisation test (SEM, TEM, EDS, TGA, XRD and ICP analyses) was shown successful synthesis of Mn‐doped ZnS quantum dots. Chondrosarcoma cancer cell viability was significantly reduced when cells were treated with MPA‐capped Mn‐doped ZnS quantum dots‐chlorin e6 with spermine linker and with covalent attachment (P  ≤ 0.001). These results indicate that X‐ray can activate the quantum dot complexes for cancer treatment, which can be a novel method for treatment of chondrosarcoma.Inspec keywords: semiconductor quantum dots, X‐ray diffraction, transmission electron microscopy, cadmium compounds, cellular biophysics, drugs, manganese, biomedical materials, cancer, quantum dots, nanofabrication, ultraviolet spectra, zinc compounds, fluorescence, scanning electron microscopy, nanoparticles, nanomedicine, bone, photochemistry, photodynamic therapy, tumours, II‐VI semiconductors, laser applications in medicineOther keywords: noncovalent methods, photodynamic activation, chondrosarcoma cancer cells, chondrosarcoma cancer cell viability, quantum dot complexes, cancer treatment, malignant cancer, routine treatments, radiotherapy, therapeutic methods, Mn‐doped zinc sulphide quantum dots, in vitro study, MPA‐capped Mn‐doped ZnS quantum dots‐chlorin e6, nanoparticle‐photosensitiser conjugated type, ZnS, Mn, ZnS:Mn  相似文献   
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