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A large number of Song Dynasty artifacts and decoration images in Song tombs unearthed in Sichuan area are rich in content, unique in shape, and ingenious in composition. They are an important part of the history of ancient Chinese art and an important physical example for the study of ancient Chinese history. This article aims to use modern computer science and technology such as 3D modeling to store unearthed cultural relics and their exquisite images, restore artifacts, realize the matching of plane photos and 3D models, and visually present the overall appearance of the relics, thereby providing more abundant materials to promote archeology for the public and museum exhibitions.

We report herein a facile electrochemical approach to synthesizing various layered composite films of nanomaterials and conducting polymers, called nanoveneers. Layered structures of polypyrrole film with single-walled carbon nanotubes (SWNTs), graphene, and Au nanoparticles have been obtained by electropolymerization of pyrrole molecules on a heavily doped silicon wafer preloaded with target conductive nanomaterials. A free-standing, transparent, and highly conductive composite film was achieved after peeling off from a silicon wafer. Different from traditional homogeneous composite materials, such kinds of nanoveneers combined to the best extent the structural continuity and processability of conducting polymers with the high conductivity and functionality of discontinuous SWNTs, graphene, and other nanomaterials. The layered electrochemical deposition provides a great freedom for constructing various nanostructures with well-controlled geometry and thus physicochemical properties, as demonstrated by SWNT/polypyrrole nanoveneers. These nanoveneers are particularly attractive in areas of chemical sensors, labels, transparent electronics, and optoelectronics.

We present a general selective positioning and integration technique for fabricating single-walled carbon nanotube (SWNT) circuits with preselected individual SWNTs as building blocks by utilizing poly(methyl methacrylate) (PMMA) thin film as a macroscopically handlable mediator. The transparency and marker-replicating capability of PMMA mediator allow the selective placement of chirality-specific nanotubes onto predesigned patterned surfaces with a resolution of ca. 1 mum. This technique is compatible with multiple operations and p-n conversion by chemical doping, which enables the construction of complex and logic circuits. As demonstrations of building SWNTs circuits, we fabricated a field effect inverter, a 2 x 2 all-SWNT crossbar field effect transistor (FET), and flexible FETs on plastic with this technique. This selective positioning approach can also be extended to construct purpose-directed architecture with various nanoscale building blocks.

In the present study, individual suspended single-walled carbon nanotubes (SWNTs) were prepared and the temperature coefficients of Raman frequency of 13 SWNTs were measured. It is found that the t...

We utilize an ac feedback signal to control the size of Cu nanogaps by electrochemically depositing or dissolving copper onto pre-patterned electrodes. The ac frequency in this work was set to 820 Hz, at which the capacitive reactance contributes notably to the gap impedance. As a result, distinct changes can be observed in the monitored signals at relatively large gap size, as compared with the high sensitivity of resistive reactance to small gap distance when the frequency is set lower. Within the present parameter, we have prepared nanoscale gaps ranging from tens of nm to sub-10 nm by carefully choosing the subsequent deposition or dissolution time.

By using the specifically designed multigap nanoelectrodes, we demonstrated an effective approach for the simultaneous dielectrophoretic separation and assembly of metallic and semiconducting single-walled carbon nanotubes (SWNTs). An approximate metallic-semiconducting-metallic multiarray structure was created by an inward-propagative sequential assembly of SWNTs under ac electric field. Such kinds of SWNT multiarray structures exhibited ultra-low-power consumption and excellent thermal sensing performances with the sensitivity being dependent on the number of gaps: the more gaps, the higher sensitivity. The effective separation of metallic and semiconducting tubes in different gaps is believed to be responsible for the improved sensitivity to temperature.

This paper describes a negative nanoimprint lithography (N-NIL) technique for fabricating metallic nanostructures via combining conventional nanoimprint lithography (NIL) with wet chemical etching. Various metallic nanostructures such as gold grating, gold/chromium alternate bimetallic grating and gold nanoelectrode arrays, which are negative replications of the stamp pattern, have been fabricated with N-NIL. This method has demonstrated its advantages on varying the feature size of obtained metallic nanostructures with a single stamp as well as on fabricating bimetallic nanostructures. In addition, it offers a unique path to fabricate micro?nano complex structures in a single imprint process, which compensates the limitation of conventional nanoimprint lithography and maintains the advantages of conventional nanoimprint lithography such as high throughput, low cost and sub-100?nm resolution.

We report a novel electric-field-enhanced chemical assembly approach for fabricating highly aligned SWNT arrays on a solid surface with remarkably improved efficiency and packing density, which is very important for the real applications of carbon nanotube arrays. With the enhancement of the electric field, the assembling kinetics of SWNTs is remarkably speeded up to effectively decrease the assembling time, and the packing density can even exceed the saturated density of conventional assembly method by four times within only half an hour. The molecular dynamics simulation results illustrated the alignment of SWNTs with their long axes along the electric flux in solution, leading to the increase of packing density and efficiency through overcoming the steric hindrance of the "giant" carbon nanotubes.

Single-walled carbon nanotubes (SWNTs) are promising building blocks for nanoelectronics. However, because of the mixture of metallic and semiconducting single-walled carbon nanotubes (m-SWNTs and s-SWNTs), it is necessary to identify them for nanodevice integerations. In this work, we have observed obvious electrodeposition differences of ultralong m-SWNTs and s-SWNTs. Using high-resolution atomic force microscopy (AFM) and field emission scanning electron microscopy (FE-SEM), particle densities along different carbon nanotubes were examined. Interestingly, m-SWNTs and s-SWNTs showed obviously different deposition behaviors, i.e., exponential decay of particle densities with different decay coefficients. This electrochemical approach can be used for a simple identification of m-SWNTs and s-SWNTs.

We presented a controllable yet simple approach for fabricating an air-stable single-walled carbon nanotube (SWNT) diode with the atomic force microscopy (AFM) manipulation technique. The AFM tip w...

LB films of a novel azobenzene derivative were fabricated and characterized by AFM, Raman microscopy, and polarized transmission FTIR spectroscopy. The AFM and Raman microscopic data revealed a well-ordered uniform structure of the film, and the dichroism in two perpendicular polarized FTIR suggested that there exist two types of hydrogen-bonded carboxyl groups, which are orientated in planes perpendicular to each other, forming a two-dimensional inter-molecular hydrogen-bonded structure in the LB film.

Both the Langmuir and Langmuir-Blodgett films of two C 60 -glycine ester derivatives, C 60 (C 6 H 9 NO 4 ) ( 1 ) and C 60 (C 8 H 13 NO 4 ) ( 2 ), have been prepared at the air/water interface. The Langmuir films can be readily transferred onto hydrophilic quartz substrates in Z type to form LB films. The LB film of 1 has good vertical homogeneity as indicated by UV-VIS spectra and a SHG study. The second- and third-order molecular hyperpolarizabilities β and γ have been determined to be (2.3 ± 1.0) × 10 −29 , 3.4 × 10 −31 esu for 1 and (1.9 ± 0.8) × 10 −29 , 3.3 × 10 −31 esu for 2 , respectively.

In this work, we have demonstrated that the local deformation at the crossed carbon nanotube (CNT) junctions can introduce significant tunable local gate effect under ambient environment. Atomic force microscope (AFM) manipulation of the local deformation yielded a variation in transconductance that was retained after removing the AFM tip. Application of a large source-drain voltage and pressing the CNT junction above a threshold pressure can respectively erase and recover the transconductance modulation reversibly. The local gate effect is found to be independent of the length of the crossed CNT and attributed to the charges residing at the deformed junctions due to formation of localized states. The number of localized charges is estimated to be in the range of 10(2) to 10(3). These results may find potential applications in electromechanical sensors and could have important implications for designing nonvolatile devices based on crossed CNT junctions.

We demonstrate herein that organic metal tetrathiafulvalene-tetracyanoquinodimethane (TTF-TCNQ) can serve as an ideal material for source and drain electrodes to build unipolar p-type single-walled carbon nanotube (SWNTs) field-effect transistors (FETs). SWNTs were synthesized by the chemical vapor deposition (CVD) method on silicon wafer and then TTF-TCNQ was deposited by thermal evaporation through a shadow mask to form the source and drain contacts. An SiO2 layer served as the gate dielectric and Si was used as the backgate. Transfer characteristics show that these TTF-TCNQ contacted devices are Schottky barrier transistors just like conventional metal contacted SWNT-FETs. The most interesting characteristic of these SWNT transistors is that all devices demonstrate the unipolar p-type transport behavior. This behavior originates from the unique crystal structure and physical properties of TTF-TCNQ and this device may have potential applications in carbon nanotube electronics.

Nickel oxide nanowires modified by poly(vinylpyrrolidone) (PVP) were synthesized via a simple chemical pattern. For the first time NiO nanowires with diameters ranging from 40 to 100 nm with the expected ratio (length vs diameter) ranging from 54 to 90 were grown using a simple solution-phase approach (mild method). These nickel nanowires exhibited unique photoluminescence features and displayed a significant UV luminescence. X-ray absorption near-edge spectroscopy has been used to characterize the local Ni environment and identify the electronic structure. Comparing experimental and theoretical spectra at the Ni and O K edges, we determine the lattice distortion via the analysis of the characteristic preedge features and the multiple-scattering structures detected in the X-ray absorption near-edge structure spectra. The correlation between experimental features and the disordered or distorted local structures is also discussed.

We demonstrated the controllable interconnection of single-walled carbon nanotubes (SWNTs) under alternating current (ac) electric field. The interconnected carbon nanotubes were found to be parallel with the electric flux and increased abruptly with deposition time following a self-accelerating process. Theoretical simulation indicates that the alignment and the interconnection of carbon nanotubes were induced by the dielectrophoresis force and the electric field redistribution at the nanotube apexes.

We demonstrate here a PMMA-mediated nanotransfer printing technique for reliably transferring nanoscale building blocks and sequentially building purpose-directed nanostructures. The utilization of PMMA film as a mediator introduced several features to this transfer approach, such as high efficiency, fidelity, universality, controllability, and multilevel transferability. Various nanostructures, such as an SWNTs-on-SAM structure, high-density crossbar array of SWNTs, a hybrid n-ZnO nanowire/p-SWNT cross-junction, a gold nanostructure-SAM-gold sandwich structure, a zigzag array of SWNTs, and gold nanobowl array were generated with this transfer approach. A metallic-semiconducting SWNT cross circuit was built to demonstrate its potential application in fabricating nanoelectronic devices. This technique paves the way to generate various structures with homo- or heterogeneous nanoscale building blocks, which facilitates exploring their fundamental properties and building novel devices.

Chemical Force Microscopy (CFM) was used to study the electrochemical behavior of azobenzene-terminated self-assembled monolayers (SAMs). Both the gold-coated AFM tip and the gold-coated silicon substrate were modified with a 4-((N-(2′-mercapto-ethyl)-amino) carbonyl) azobenzene monolayer. For such a system, only when the reduction/oxidation reaction of azobenzene group occurs, the adhesion force between the tip and sample shows a drastic change, demonstrating the ability of CFM in monitoring the electrochemical transformation of an azobenzene group.

The electrochemistry of diamond has gained much importance due to its stability, low background current and wide potential window in aqueous electrolytes. We have used high quality diamond films both from fundamental and applied viewpoints. The detection of biologically important compounds such as dopamine was found to be possible at very low concentrations even in the presence of ascorbic acid, which interferes frequently in biological systems. Similarly, oxidation of nicotinamide dinucleotide (NADH) was observed, with a well defined cyclic voltammogram even in the micromolar range. The electrochemical reduction of C60 at diamond electrode was studied in acetonitrile-toluene mixture, and six reduction peaks were observed at room temperature.

By fabricating a PMMA control strip at the SWNTs-electrode contact area to screen off the water gate effect, metallic and semiconducting SWNTs were easily identified during the conventional electropolymerization process.

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We demonstrated a prototype of nanoelectromechanical switch which was fabricated with single-walled carbon nanotubes (SWCNTs). An alternating current electric field was utilized to assemble interconnected SWCNTs suspended over the focused ion beam lithography fabricated trenches on the electrode surface. By controlling the electromechanical coupling between the electrostatic and elastostatic forces acting on the SWCNTs, we realized the on and off states of the SWCNT switches. Both two-terminal and three-terminal measurements have been conducted and indicated repeatable switch effects.

An electrochemical technique for fabricating nanogaps is proposed, which utilizes an in situ gap-impedance-tuning mechanism to realize precise control of gap separation. Nanogap electrodes with gap separation from tens of nanometer to sub 10 nm have been fabricated by combining conventional photolithography and this controlled electrodeposition technique. The gap separation can be tuned by changing monitoring parameters based on a homemade electrochemical setup, which provides high sensitivity and reproducibility. In addition, a possible mechanism for controlling gap separation at tens of nanometer level at present conditions was discussed.