3439927162?profile=original1. Wafer Extension for Cost-Effective Front to Back Side Alignment

 

Authors: S. Brabender , K. Kolander, K.T. Kallis, H.L. Fiedler

 

Abstract: This work presents a cost-effective and simple possibility to outperform the potential of a standard single side mask aligner. The limited functionality is extended to the capability of back side alignment with minimal effort without additional knowledge and integration of new process technologies. The whole presented process flow performs without the necessity of additional equipment as infrared back side wafer alignment kits or additional etching processes or clamps and brackets. The result is a front to back side alignment process with satisfactory deviation.

 

Direct link: http://www.scientific.net/JNanoR.27.1

 

2. Study of Memristive Elements Networks

 

Authors: Ioannis Vourkas, Georgios Ch. Sirakoulis

 

Abstract: The existence of the fourth fundamental circuit element, the memristor, was first postulated over 30 years ago by Leon Chua. The implementation of the first modern memristor prototype by Hewlett Packard Laboratories in 2008 initiated a great scientific interest for these unique nanoelectronic devices and currently, there is a growing variety of systems that exhibit memristive behavior. However, most of the research has focused on the properties of the single devices, therefore very little is known about their response when these devices are organized into networks. In this work, the composite characteristics of memristive elements connected in network configurations are studied and the relationships among the single devices are investigated. We finally show how the threshold-dependent nonlinear memristive behavior could be elaborated to make possible the development of novel and sophisticated digital/analog memristive nanosystems.

 

Direct link: http://www.scientific.net/JNanoR.27.5

 

3. Study of the Structural and Mechanical Properties of Nanocrystalline TiAlSiN Gradient Coatings

 

Authors: T. Cholakova, V. Chitanov, D. Chaliampalias, Lilyana Kolaklieva, R. Kakanakov,
Ch. Bahchedjiev, N. Petkov, Ch. Pashinski, G. Vourlias, N. Vouroutzis, E. Polychroniadis, Y. Wang,
E.I. Meletis

 

Abstract: A study of the structural and mechanical properties of nanocrystalline TiAlSiN gradient coatings deposited by cathodic arc deposition techniques at 500 °C and post-annealed at 525 °C is presented. Analysis of the coatings, chemical composition and microstructure revealed that the coatings have a structure based on (Ti, Al)N nanocrystals with an average size of 10 nm embedded in an amorphous Si3N4 phase. The study of the mechanical properties showed that post-annealing causes improvement and increase of the coatings hardness. A maximum hardness of 48 GPa and elastic modulus of 560 GPa were measured. Also, excellent adhesion to the WC-Co substrate was observed in the post-annealed coatings.

 

Direct link: http://www.scientific.net/JNanoR.27.15

 

 

4. Effects of Annealing Ambient on Electrical Properties of LaBaCo2O5+δ Thin Films

 

Authors: Ming Liu, Chun Rui Ma, Eric Enriquez, Xing Xu, Shan Yong Bao, Chong Lin Chen

 

Abstract: Highly epitaxial LaBaCo2O5+δ thin films are successfully fabricated and annealed in different ambient conditions. The LaBaCo2O5+δ thin films under O2 and N2 annealing atmosphere are c-axis oriented with the interface relationship of [100]LBCO//[10LAO and (001)LBCO//(001)LAO. Annealing the film in N2 ambient significantly increases the resistivity and magnetoresistance comparing to the films annealed in O2 ambient. The magnetoresistance after annealing in N2 is almost more than twice of the magnetoresistance after annealing in O2. The result revealed that the electrical properties of the film are highly influenced by annealing atmosphere, indicating that the physical properties can be controlled by adjusting the post annealing atmosphere.

 

Direct link: http://www.scientific.net/JNanoR.27.25

 

5. Characterization of Surface Nanostructures on“Thin” Polyolephine Foils

 

Authors: Alena Řezníčková, Zdeňka Kolská, Petr Sajdl, Václav Švorčík

 

Abstract: Surface properties of nanostructures on 7 polyolephine foils were characterized using different analytical methods to discuss an effect of halogen presence in polymer chain to surface properties. Both sides of these foils were examined and compared. Surface roughness and morphology were determined by atomic force microscopy, contact angle by goniometry, surface polarity by electrokinetic analysis. X-ray photoelectron and ultraviolet visible spectroscopies were used for determination of surface chemistry. Combination of different analyses gives complex information about surface properties of the foils, which may be of importance for any future experiments, as well as for their application e.g. in tissue engineering and electronics.

 

Direct link: http://www.scientific.net/JNanoR.27.31

 

6. A Brief Introduction to the Development of Biogenic Synthesis of Metal Nanoparticles

 

Authors: Samiran Mondal, Saswati Basu, Naznin Ara Begum, Debabrata Mandal

 

Abstract: Though there are a numerous methods for chemical synthesis, biogenic synthesis of nanoparticles offers an attractive alternative to chemical synthesis methods. Therefore scientists are continuously engaged in searching hazard free, environment friendly methods of synthesis of nanoparticles with tailor-made structural properties using benign starting materials. Recently several groups have achieved success in the synthesis of Ag, Au, Pd nanoparticles with specific shape and size using extracts obtained from micro-organisms as well as various plant extracts. It will be a highly interesting problem to modify the procedure to develop green-chemical means of synthesizing “tailor-made” monodisperse nanoparticles of single polygonal particle morphology, exclusively. The main objective of this brief article is to give an idea about the most reliable, cost-effective and environment friendly synthetic protocols for metal nanoparticles of different size, shape, composition, and with a high degree of monodispersity.

 

Direct link: http://www.scientific.net/JNanoR.27.41

 

7. Physical and Antimicrobial Characterization of Self Assembled Silver Nanoparticle/Chitosan onto Low Density Polyethylene Film as Active Packaging Polymer

 

Authors: Maryam Jokar, Russly Abdul Rahman, Luqman Chuah Abdullah

 

Abstract: Colloidal Silver nanoparticles with a size of 5 nm produced by chemical reduction using poly ethylene glycol (PEG 200). Layers of silver nanoparticles and chitosan were deposited onto low density polyethylene (LDPE) substrate by layer by layer (LBL) self-assembly technique. Silver nanocomposite films were built by sequential dipping of LDPE film in either anionic silver nanoparticles or cationic chitosan. Silver nanoparticles and chitosan led to the formation of nanocomposite films possessing antimicrobial properties with the thickness of 2, 4, 8, 12 and 20 layers. Silver nanocomposite films were characterized by atomic force microscopy (AFM). Thermal, mechanical and barrier properties of LBL deposited nanocomposite films were investigated. Results showed that the LBL deposition of silver nanoparticles and chitosan increased the crystallinity of the composites and also improved mechanical and barrier properties of LDPE film significantly (p<0.05). Antimicrobial activity of silver nanocomposites against Escherichia coli and Staphylococcus aureus was evaluated. Growth kinetic parameters of E.coli and S.aureus affected by silver nanocomposites were calculated by modeling of absorbance data according to Gomperz equation. LDPE-silver nanocomposite affected bacterial growth parameters significantly (p<0.05). The specific growth rate reduced from 0.30 to 0.11 h-1 for E. coli and decreased 0.27 to 0.06 h-1 for S. aureus.

 

Direct link: http://www.scientific.net/JNanoR.27.53

8. Role of Vacancies in Zigzag Graphene Nanoribbons: An Ab Initio Study

 

Authors: Khaldoun Tarawneh, Nabil Al-Aqtash

 

Abstract: We have studied the effects of vacancies on the structural, electronic and magnetic properties of zigzag-edged graphene nanoribbons (ZGNRs). Our calculations were carried out using an ab initio density functional pseudopotential computational method combined with the generalized gradient approximation for the exchange-correlation functional. The equilibrium geometries, electronic charge spin density distributions, electronic band structures, and magnetic moments were examined in the presence of single vacancy and double vacancies. Structural optimization showed that vacancies induce substantial structural changes in ZGNRs. We found that introducing vacancies into ZGNR changes the spatial distribution of neighbor atoms, particularly those located around the vacancies. Our calculations showed that the vacancies have significant effect on the magnetization of ZGNR. The calculations showed that the changes in the structural geometry, the electronic structure and the magnetization of ZGNR depend on the location of the vacancies with respect to the ribbon edges. These results suggest that vacancy defects can be used to modify the electronic and the magnetic properties of ZGNR.

 

Direct link: http://www.scientific.net/JNanoR.27.65

 

9. Antheraea pernyi Silk Fibroin Nanoparticles for Drug Delivery

 

Authors: Shen Zhou Lu, Juan Wang, Li Mao, Gui Jun Li, Jian Jin

 

Abstract: Silk nanoparticles were easily obtained from regenerated Antheraea Pernyi Silk Fibroin (ASF). The morphology and average size of the silk particles was sensitive to pH value of fibroin solution. The diameter of nanoparticles prepared was in the range of 30 nm to 1000 nm with a narrow size distribution. On this process, the molecular conformation of regenerated ASF changed from α-helix to β-sheet structure. The shape of prepared nanoparticles were regular spherical structure when the pH value was about 4.3 (pI) in ASF solution. Doxorubicin hydrochloride (DOX) was loaded in the ASF particles as drug release model and the drug-loading ratio was 3.4 %. The release rate of DOX from ASF nanoparticles was pH sensitive. After 23 days release, there was still 84% DOX in the ASF nanoparticles. The result suggested that the ASF nanoparticles might be suitable microcarriers for drug delivery.

 

Direct link: http://www.scientific.net/JNanoR.27.75

 

10. PEG Functionalized Gold Nanoparticle Loaded PLGA Films for Drug Delivery

 

Authors: D. Dixon, B.J. Meenan, J. Manson

 

Abstract: A novel composite of poly (ethylene glycol) (PEG) functionalized gold nanoparticles (AuNP-PEG) dispersed within Poly (lactic-go-glycolic) (PLGA) films, were prepared to demonstrate the concept of a combined targeted and sustained implant material. This technology offers the promise of improved therapies for difficult to treat tumors such as Gliomas. Gold nanoparticles (AuNPs) synthesized via a modified Turkevich method, were functionalized with thiol terminated polyethylene glycol (PEG), washed using centrifugation, dried, re-suspended in a solution of PLGA in dichloromethane and finally vacuum dried to produce the solvent cast films. The degradation and nanoparticle release profile of these films were studied by immersion in PBS media at 37 °C over periods of up-to 58 days. Thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), scanning electron microscopy (SEM) and attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR) was conducted. The release of the AuNPs-PEG nanoparticles during degradation was studied using inductively coupled plasma mass spectroscopy (ICP-MS). It was observed that the AuNP-PEG nanoparticles were individually dispersed within the PLGA and that their addition extended the degradation time of the PLGA film, but did not appear to alter the nature of degradation. The nanoparticle release from the composite films displayed an approximately zero-order release profile.

 

Direct link: http://www.scientific.net/JNanoR.27.83

 

11. Preparation of Fe2+-Doped Silica Sol and its Application in Silk Modification

 

Authors: Tie Ling Xing, Wei Zhang, Zhi Juan Liu, Ren Cheng Tang, Guo Qiang Chen

 

Abstract: Fe2+ doped silica sol was prepared using tetraethoxysilane (TEOS) as precursor, ethanol as solvent, hydrochloric acid as catalyst and aqueous solution of ferrous iron by sol-gel method under the follow condition: [TEO:n [EtO:n [H2=1:6:11, reacted at 70°C for 120 min with stirring. Through characterization of the prepared silica sol using particle size analyzer, X-ray diffraction (XRD) and UV-visible spectrum, it could be concluded that even and stable silica sol with nanosize and color was prepared. The prepared Fe2+ doped silica sol was applied in silk modification to endow silk with multifunctional properties and color. X-ray Photoelectron Spectroscopy (XPS) and atomic force microscopy (AFM) indicated that Fe2+-doped silica sol was treated onto the surface of silk fabric. The results showed that the Fe2+ doped silica sol treated silk had good flame retardance, water repellence and antistatic property. At the same time, silk fabric treated by the Fe2+-doped silica sol was also endowed with color.

 

Direct link: http://www.scientific.net/JNanoR.27.95

 

12. Fabrication and Characterization of Chinese Drug-Loaded Nanoporous Materials

 

Authors: Lan Xu, Na Si, Hong Ying Liu

 

Abstract: Chinese drug-loaded nanoporous materials were prepared from electrospinning Poly (butylenes succinate) (PBS) solutions with an additive of Chinese drug and a mixed solvent of chloroform and iso-propylalcohol in a single processing step. Characterizations of the samples, such as morphology, wettability and permeability, were studied by means of scanning electron microscope, full automatic micro droplet wettability measurement instrument and fabric air permeability performance tester. The results showed these characterizations could be controlled by adjusting electrospinning parameters such as flow rate and drug concentration. And the electrospun nanoporous materials might offer the potential for direct fabrication of biologically based and high-surface-area porous materials.

 

Direct link: http://www.scientific.net/JNanoR.27.103

 

13. Lightning-Like Charged Jet Cascade in Bubble Electrospinning with Ultrasonic Vibration

 

Authors: Hong Yan Liu, Hai Yan Kong, Mei Zhen Wang, Ji Huan He

 

Abstract: Lightning is a natural phenomenon caused by an atmospheric electrical discharge, and lightning strikes are of hierarchical structure. Similar phenomenon is first observed in a charged jet in the presence of a high electrostatic field, the process is widely adopted for fabrication of superfine fibers, and its mechanism of lightning-like charged jet is still unknown. Our observation reveals that a daughter jet can be ejected from the surface of a micro/nanoscale charged jet to form an initial two-stage cascade, whereby the daughter charged jet can reduce size over three orders of magnitude, while at the ultimate stage, the jets have almost same size from several nanometers to dozens of nanometers. The origin of this phenomenon might be central to nanotechnology. Here we demonstrate that an electrostatic field can accelerate a charged jet, and the surface charge repels each other. When the repelling force reaches a threshold to overcome its surface tension, one or more daughter charged jets are ejected from the surface. The daughter jets behave similarly to the initial jet, the process is iterative, creating a lightning-like multi-stage cascade. This observation opens the door to mimicking the lightning to produce two dimensional superfine fiber web with hierarchical structure.

 

Direct link: http://www.scientific.net/JNanoR.27.111

 

14. Preparation, Characterization and Ionizing Radiation Protection Properties of Electrospun Nanofibrous Mats Embedded with Erbium Oxide (Er2O3) Nanoparticles

 

Authors: Fu Juan Liu, Qiu Na Cui, Ji Huan He, Dong Dong Fei

 

Abstract: Ionizing radiation directly causes serious damage to human health, and a protective system capable of absorbing or reflecting ionizing radiation is required urgently. In this work, electrospun poly (vinyl alcohol) (PVA) and Poly (vinyl Alcohol)/Erbium Oxide (PVA/Er2O3) nanocomposite fibrous mats were fabricated. These PVA or PVA/Er2O3 composite nanofibers were completely characterized using scanning electron microscopy (SEM), Fourier-transform infrared (FTIR) spectroscopy, Thermogravimetric Analysis (TGA) and X-ray photoelectron spectroscopy (XPS). Furthemore, air permeability and ionizing radiation protection properties of these mats were also measured. Under a certain constant electropinning condition, the PVA or PVA/Er2O3 composite nanofibers showed an excellent morphology. The ionizing radiation protection capability of nanofibrous mats is considerably improved when incorporated with Er2O3 nanoparticles.

 

Direct link: http://www.scientific.net/JNanoR.27.121

 

15. Study of Electrospun Chitosan Nanofibrous Coated Webs

 

Authors: Mukesh Kumar Sinha, Biswa Ranjan Das, Anurag Srivastava, Arvind Kumar Saxena

 

Abstract: Fabricated nanowebs are successfully coated with polypropylene spun bonded non-woven fabric with various coating density ranges from 0.25-1.2 gsm. This study describes an electrospinning coating process of pure Chitosan dissolved in TFA and DCM and its detailed characterizations. The optimal solution condition for electrospinning was studied and, thereby, the process was successfully established. The best optimal condition: 11 % Chitosan was successfully electrospun (superlative web structure) in the electric field of 75 KV, distance between spinning electrodes 135 mm and rotation of spinning electrode 5 rpm (throughput). Once it was determined the ideal condition for fabricating web thereafter under identical conditions electro coating process was done by varying collector speed. The resultant nanofibrous web was found to be uniformly coated having mean fiber diameter ranges from 1210-1221 nm. AFM microphotographs indicated the interconnected porous structure of the prepared Chitosan web. Fibrous break down at a solution concentration (2 & 5 %) was revealed by AFM and FESEM images. At higher concentration (14%) web spinability was poor in the form of lumps deposition. Morphology of spun web was greatly influenced by coating density. Thus, these nanofibrous coated membranes have great potential for using as a layer for developing futuristic antimicrobial, biomedical and filtration clothing. Moreover, the developed coated web has a significantly higher production rate (approx 0.25 g/m2min) is potential for commercial viability and could be translated into bulk production.

 

Direct link: http://www.scientific.net/JNanoR.27.129

 

16. Modification of Si-Based Consolidants by the Addition of Colloidal Nanoparticles: Application in Porous Stones

 

Authors: E. Ksinopoulou, A. Bakolas, A. Moropoulou

 

Abstract: Si-based consolidants, most widely used in the restoration of porous stones exposed to the environmental decay mechanisms, present some serious limitations, such as the tendency to crack and shrink during drying. This deficiency has been the focus of several studies with the objective of modifying and improving the above mentioned materials. The addition of nanoparticle dispersions into silica matrix has been found to enhance their effectiveness in several respects. Objective of the current research was to study the preparation of particle modified consolidants (PMC), consisting of an ethyl silicate matrix loaded with colloidal oxide titania (TiO2) particles and silica (SiO2) nanoparticles and the evaluation of their consolidation effect, applied to different porous limestones. Two compositions were prepared and then evaluated based on their stability in the liquid phase, the particle size, the% solids content and their morphological characteristics during the drying process. The characterization of the particles is made through dynamic light scattering (DLS). Penetration depth of the material is examined by scanning electron microscopy (SEM-EDAX). The color changes of the treated surfaces were measured by a portable spectrophotometer before and after treatment. Changes in the porosity and characteristics of the microstructure were determined by applying mercury porosimetry in untreated and treated samples. Based on the techniques applied, PMCs appear to be promising materials in stone consolidation, as they show a reduction of silicate network shrinkage and cracking during drying compared with the silicon-based consolidant. Treatment causes some changes in the properties of the substrate such as a reduction of the % water uptake (up to 15%) as well as an increase in the elastic modulus (up to 10%).

 

Direct link: http://www.scientific.net/JNanoR.27.143

 

17. Multi-Physics Coupled FEM Method to Simulate the Formation of Crater-Like Taylor Cone in Electrospinning of Nanofibers

 

Authors: Yong Liu, Jia Li, Yu Tian, Jian Liu, Jie Fan

 

Abstract: Crater-like Taylor cone electrospinning is a novel, simple, and powerful approach to mass produce nanofibers. The Taylor cone, crater-like liquid bump on the free liquid surface, in this electrospinning process plays a key role to produce multiple fluid jets which finally solidifies nanofibers. A multi-physics coupled FEM method was employed to simulate the dynamic formation process of crater-like Taylor Cone in crater-like electrospinning. A blended k−ω /k−ε model for turbulence and dynamic overset grids to resolve large amplitude motions were used to simulate two-dimensional uncompressed flow, which was described in axisymmetrical coordinates. The numerical calculation results were obtained by a computational fluid dynamics (CFD) method. The effect of gas flow on the formation of crater-like Taylor cone and the production of nanofibers were also discussed. The experiments were carried out to validate the numerical results. The Polyvinyl Alcohol (PVA)/ distilled water solution with 18wt% and the air pressures ranged varied from 4 to 50kPa were used in our experiments. The results showed that the numerical results were in good agreement with the experimental results. This work provides a deep understanding of the mechanisms of micro fluid jets production in electrospinning processes and two-phase flow in specific type of industrial equipment.

 

Direct link: http://www.scientific.net/JNanoR.27.153

 

18. Low-Temperature Growth of Vertically Aligned Carbon Nanotubes on a Glass Substrate Using Low Power PECVD

 

Authors: M.K. Tabatabaei, H. Ghafoori Fard, J. Koohsorkhi

 

Abstract: In the traditional PECVD method for growing carbon nanotubes (CNTs), the electric field is an important parameter. Its role is to orient CNT growth and dissociate the H-C bond from hydrocarbon gases. Therefore, high energy ions, molecules, and radicals as plasma elements can affect the verticality of CNTs. In this paper, a new configuration for an electric field for the growth of field-oriented and long CNTs on a glass substrate at temperatures below 400°C is reported. Simulation and experimental data show that CNTs are grown at a considerably lower voltage than traditional methods. Using this method, growing vertical CNT on such low-cost substrate glass is more possible for CNT-based devices and bio-applications where price is important.

 

Direct link: http://www.scientific.net/JNanoR.27.163

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