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Luminescent hydrogen-bonded organic frameworks (HOFs) have attracted increasing attention due to their corresponding luminescence that enables readily visualization of structural dynamics. HOFs wit...

With the rapid development of nanotechnology, the size of a device reaches sub-nanometer scale. The larger resistivity of interconnect leads to serious overheating of integrated circuits. Silicon-based electronic devices have also reached the physical limits of their development. The use of carbon nanotubes instead of traditional wires has become a new solution for connecting nano-structures. Nanocluster particles serving as brazing material play an important role in stabilizing the connection of carbon nanotubes, which places higher demands for nanoscale manipulation techniques. In this paper, the dynamic processes under different operating scenarios were simulated and analyzed, including probe propulsion nanoparticle operation, probe pickup nanoparticle operation and probe pickup nanocluster particle operation. Then, the SEM (Scanning Electron Microscope) was used for nanoparticle manipulation experiments. The smallest unit of carbon nanotube wire was obtained by three-dimensional (3D) construction of a carbon nanotube–silver nanocluster particle (CN-AgNP), which verified the feasibility of 3D manipulation of carbon nanotube wire construction. The experiments on the construction of carbon nanotube–nanocluster particle structures in three-dimensional operation were completed, and the smallest unit of carbon nanotube wire was constructed. This nano-fabrication technology will provide an efficient and mature technical means in the field of nano-interconnection.

Summary This article proposed a high-performance triboelectric-electromagnetic hybrid wind energy harvester (WEH). By adopting the revolution and rotation movements of tapered rollers, which serve as both the rotor of the electromagnetic generator (EMG) part and freestanding layers of the triboelectric nanogenerator (TENG) part, the WEH can work as a sustainable power source and a self-powered wind speed sensor. When the wind speed is 12 m/s, super-high open-circuit voltage peaks of 47.4 and 683 V can be achieved by the EMG and TENG, respectively, corresponding to the high-power outputs of 62 and 1.8 mW. It was demonstrated that the WEH can easily light up over 600 red light-emitting diodes and even a 5-W globe light. A self-powered wireless temperature and humidity sensing network was also systematically demonstrated. In summary, the proposed WEH exhibits bright future toward IoT applications, such as in border detection, smart buildings, and so on., Graphical abstract, Highlights • A triboelectric-electromagnetic hybrid generator based on tapered rollers is proposed • The high-performance WEH has been systematically optimized and tested • A self-powered anemometer system has been successfully established • The WEH shows bright prospect in future IoT applications, Electromagnetics ; Energy Resources ; Energy Systems ; Device

Sensors based on triboelectric nanogenerators have been widely used for energy harvesting and sensing applications, however, the applications of multidimensional information perception and interactive control are insufficient. In this paper, we present an ultra-stretchable triboelectric strip sensor (TSS) using triboelectric mechanism for controlling the objects in three-dimensional space. This facile and low-cost TSS is mainly composed of a parallel structure including three symmetric sensor strips fixed on the base and a mobile stage connected with them. Based on the coupling effect of triboelectrification and electrostatic induction, the length changes of each strip with the same finger contacting point generate different signal output ratios from two terminal electrodes, functioning as the interactive interface for multi-dimensional sensing and controlling. Hence, the parallel sensor strips structure can realize the sensing and controlling in three degrees of freedom of linear motion and two degrees of freedom of rotational motion, and resultant sensing ranges are X, Y, Z, α and β (20 mm, 20 mm, 30 mm, 36°, and 36°). In terms of manipulation, this is simpler than the conventional controller with rigid structure and includes additional space dimensions. Furthermore, demonstration of the TSS as human-nanomachine terminal to control the nanomanipulator in scanning electron microscope (SEM) is successfully realized with the accuracy of 10 nm. The proposed TSS shows great potential for the applications in automated control, robotics control, and Internet of Things (IoT).

Escherichia coli O157: H7 (E. coli O157: H7) is a foodborne pathogenic bacterium which can cause fever, diarrhoea and vomiting in humans. Thus, a rapid, simple, and specific bioprobe for pathogen detection in contaminated foods has been attracted more and more attention. In this work, the strong fluorescent amino-functionalized graphene quantum dots (af-GQDs) were prepared by hydrothermal method. The microtopographic height, surface morphology and spectroscopic properties of af-GQDs are characterized by the high resolution transmission electron microscope (HRTEM), atomic force microscope (AFM), UV-vis, fluorescence, Raman spectroscopic techniques. All the results showed that the af-GQDs can be effectively applied in the preparation of biocompatible immunofluorescence probe and in the detection of E. coli O157: H7. The minimum detection limit is 100 cfu/mL. It is a simple, rapid, sensitive, low-cost and easy to be popularized method, which provides a feasible way to monitor E. coli O157: H7 in food safety.

The near-field enhancement underneath the AFM tip irradiated by a laser beam is widely utilized in various nanofabrication techniques, such as nano-welding, nano-manipulation, nano-etching and so on. In this paper, a numerical model of near-field enhancement on AFM tip irradiated by annular laser beam is established using COMSOL Multiphysics. The results show that when the AFM tip is irradiated by annular laser beam, strong near-field enhancement is induced at the apex of the tip. The field distribution curve with the substrate presents a saddle shape, which demonstrates that the annular beam irradiated the AFM tip produce an extremely high near-field enhancement between the particle and the tip. In addition, the results indicate that when the AFM tip is irradiated by the annular laser with higher frequency, the near-field enhancement underneath the apex of the tip increases correspondingly. Moreover, when the irradiation angle is 60 Deg and the irradiation distance is 65 nm, the near-field enhancement reaches the peak. Based on the numerical simulation of the near-field enhancement, the system of the AFM tip irradiated by annular laser beam can be anticipated for further application in the field of nanofabrication.

Swimming micro-nanorobots have attracted researchers’ interest in potential medical applications on target therapy, biosensor, drug carrier, and others. At present, the experimental setting of the swimming micro-nanorobots was mainly studied in pure water or H 2 O 2 solution. This paper presents a micro-nanorobot that applied glucose in human body fluid as driving fuel. Based on the catalytic properties of the anode and cathode materials of the glucose fuel cell, platinum (Pt) and carbon nanotube (CNT) were selected as the anode and cathode materials, respectively, for the micro-nanorobot. The innovative design adopted the method of template electrochemical and chemical vapor deposition to manufacture the Pt/CNT micro-nanorobot structure. Both the scanning electron microscope (SEM) and transmission electron microscope (TEM) were employed to observe the morphology of the sample, and its elements were analyzed by energy-dispersive X-ray spectroscopy (EDX). Through a large number of experiments in a glucose solution and according to Stoker’s law of viscous force and Newton’s second law, we calculated the driving force of the fabricated micro-nanorobot. It was concluded that the structure of the Pt/CNT micro-nanorobot satisfied the required characteristics of both biocompatibility and motion.

The denoising of SEM images and extracting of image information have attracted attention in the micro-nano research fields. In this paper, we analyze the noise types and characteristics of SEM images and propose the method of deep convolutional neural network to denoise SEM images. On the basis of denoising, suitable methods are used to identify the position of single, multiple nanowires and positional relationship of multiple nanowires in the depth direction. Because of special imaging principles, there are many differences between SEM images and ordinary gray images. To the SEM image, noise has more significant influences on extracting information from SEM image. Samples which have various types and morphologies were observed under different types of electron microscopy and observation conditions to produce dataset. Then the supervised deep convolutional neural network was trained by this dataset, which has a good adaptive on denoising of SEM images. After denoising, the identification method of nanowires was further proposed which could accurately recognize single, multiple nanowires by canny edge detection and Hough transform, and quickly identify their positional relationship.

In this paper, we report a novel design of a microspherical lens assembly that can realize super-resolution optical imaging in air with super-wide field of view (FOV). The microspherical lens assembly is made from a barium titanate glass (BTG) microsphere that is glued to a microspherical crown lens through optical adhesive. Experimental results show that super-resolution optical imaging in air can be achieved under a regular optical microscope when the microspherical lens assembly is brought sufficiently close to the sample surface. Super-wide FOV is also achieved when a larger BTG microsphere is used and there seems no obvious limitation on the size of the BTG microsphere as long as the curvature of the microspherical crown lens is properly tuned. Simulation study suggests that the focus point of the microlens needs to close to the bottom surface of the BTG microsphere in order to achieve the super-resolution optical imaging. The novel microspherical lens assembly will make the microsphere based super-resolution imaging a step further close to practical applications.

Graphene is widely used as the basic materials of nano optical devices and sensors on account of its special structures and excellent photoelectric properties. Graphene is considered as an ideal material for photodetectors because of its ultra-wide absorption spectrum from the ultraviolet to the terahertz band, ultrahigh carrier mobility and ultrafast photoreaction speed. In this study, a photothermal nano-device was made using graphene that was transferred to an electrode using an all-dry viscoelastic stamping method. The nano-device has the advantages of simplicity, high efficiency and instant measurement. This nano-device was used to measure the light absorption of graphene, and the calculated light absorption rate of graphene is basically consistent with previous research results. Experiments on irradiation at different wavelengths and thermal heating at different temperatures show that the nano-device has an excellent response to near-infrared and mid-infrared light. The conclusions provide an experimental basis for the research, design and fabrication of nano-devices, and this device can provide an effective method for detecting light and temperature in areas such as electronic components and solar cells.

Due to the coaction of supply harmonics and the harmonics resulting from the motor structures, the mechanism and distribution characteristics of iron losses become more complicated in inverter-fed induction motors. Therefore, accurate prediction and fine analysis of iron loss are very important at the design stage of high-efficiency inverter-fed induction motors. In order to predict the iron losses accurately, this paper proposes a piecewise iron loss model whose parameters vary with the magnitude and frequency of flux density, and two additional flux density terms are introduced to the classical iron loss model considering the nonlinearity of magnetic material and harmonic fields. With this model, the iron losses are calculated for an inverter-fed 5.5 kW induction motor. The results reveal the distribution characteristics of hysteresis and eddy current losses in stator and rotor cores, and the characteristics of additional iron loss caused by harmonic fields. By the comparison of predicted and measured no-load iron loss under different supply voltages and switching frequencies, the proposed model and the analysis results are validated.

Stretchable superhydrophobic materials are of potential interest for next-generation multi-functional haptic technologies particularly suited for wearable device and artificial skin applications. However, the practical applications of stretchable superhydrophobic materials are hindered by some issues, such as low mechanical robustness, harmful chemicals, etc. Here, we partially embedded perfluorosilane-coated graphene into thermoplastic polyurethane (TPU) by a dissolution and resolidification method. Due to the exceptional physical properties of graphene, the resulting nanocomposites could maintain their superhydrophobicity after toleration of strain up to 400%, man-made destruction by hands or sandpapers, pollution by oil, immersion in various corrosive liquids, and heat treatment at 150 °C for 24 h. It should be noted that even under an ultra-large load of 2 kg (32.5 kPa pressure), this graphene composite could withstand the abrasion by sandpaper for 20.00 m without losing superhydrophobicity. More remarkably, the electrical resistance of this graphene superhydrophobic composite is sensitive to material deformation, and can be directly applied to gloves for real-time detection of human motions.

A carbon monoxide (CO) sensor based on a Michelson interferometer combined with α-Fe2O3/reduced graphene oxide quantum dots (rGOQDs) composite film is proposed and fabricated. First, a waist-enlarged taper is formed between the single-mode fiber (SMF) and the no-core fiber (NCF), then the other end of the NCF is spliced with a section of thin-core fiber (TCF). The end of the TCF is coated with a layer of silver film to enhance the reflection. Thus, a Michelson interferometer comprising SMF–NCF–TCF is formed. The α-Fe2O3/rGOQDs composite film is deposited on the outside surface of the TCF. The specific adsorption of CO by the composite film leads to a change in the sensor’s effective refractive index, realizing the detection of CO. The results show that the interference intensity of the monitoring valley decreases with increase in the concentration of CO. The sensitivity of the sensor is 0.057 dBm ppm−1, the detection limit of the sensor is 105 ppb and the response time and recovery time are 70 s and 100 s, respectively. The sensor has the advantages of high sensitivity, high selectivity and simple structure, and it is expected to be used for the detection of low concentrations of CO gas.

Non-skewed rotors can be used to eliminate the slot harmonic field, as well as, the noise and vibration can also be weakened effectively. However, it is difficult to determine the spatial distribution of the asymmetrical rotor bars and slot combinations, which can affect the loss and air-gap force significantly. Taking a 5.5kW, 4-pole induction motor as an example, this paper studies the influence of the above factors on the loss and air-gap force systematically, by using Finite Element Method (FEM), and the experiment validation on efficiency and no-load noise are also performed on a 5.5 kW prototype.

The ability to pick up a single carbon nanotube (CNT) from a bundle of CNTs is of great importance for nanodevice fabrication. In this study, we propose a nanorobotic manipulation system allowing automated pick-up of CNTs based on visual feedback. We used histogram thresholding for automatic binarization, and it clearly distinguished CNTs from the substrate and other impurities under various image brightnesses and contrasts. Furthermore, the CNT tip was successfully extracted by making use of the geometrical characteristics of the CNT. We designed a segment detection method to separate the CNT and atomic force microscope cantilever during overlapping. The contact detection between them was identified by evaluating the linearity of the fitted CNT curve. We also further analyzed the specific properties of point contact and linear contact, significantly improving the success rate of pick-up. Finally, the experimental results show that our method is highly promising for realistic fabrication of nanodevices.

This study proposes a two-term piecewise variable parameter model for precise prediction of iron losses in induction motors. In this model, two additional flux density terms reflect the non-linear magnetisation and the harmonic fields in the motors, and the main loss parameters are piecewisely variable with the magnitude and frequency of flux density, so that higher accuracy of iron loss prediction can be achieved for a large range of flux density frequencies and magnitudes. Meanwhile, the fine analysis of the fundamental and harmonic iron losses can also be carried out with the proposed model, and the influence of the harmonic fields on the hysteresis and eddy current losses can be revealed. Experimental validations are carried out on the laminated steels, DR510 and DW470, as well as, the Y132S-4, 5.5 kW and YX3-250M-4, 55 kW induction motors whose cores are made of the above steels. The experiments on the motors are performed with the voltage supply of different magnitudes, and both the proposed model and Bertotti model are used to predict the iron losses. It is shown that the iron losses predicted by the proposed model agree well with the test results over a wide range of supply voltages. This study contributes the technical support for the development of new premium efficiency motors.

A method of picking up carbon nanotubes (CNTs) from nanotube bulk by van der Waals force inside a scanning electron microscopy is presented. An atomic force microscope cantilever was employed as end effector of nanorobotics manipulators for CNT picking up. A manipulation strategy was established by analysing the van der Waals force of three different types of contacting models. Three groups of experiments were designed and carried out to investigate the effects of different factors. Factors including pickup angle, pickup contact area between the CNT and the cantilever and pickup speed of the end effector were discussed. The results shown that a pickup angle at 90.1° and a pickup speed lower than 10 nm/step with a pickup contact length more than 1.5 µm would increase the probability of picking up CNT successfully.

RNA-binding motif protein 5 (RBM5) acts as a tumor suppressor in various human cancers and presents with several important characteristics, such as the potentiation of apoptosis, inhibition of the cell cycle, and alternative splicing of Fas and caspase-2 precursor mRNA. However, its role in bladder urothelial carcinoma (BUC) remains unknown. In this study, we found that RBM5 expression was significantly down-regulated in BUC tissues when compared with the adjacent nontumor tissues. The down-regulation of RBM5 activates β-catenin, which binds to the T-cell factor/lymphocyte enhancer factor element of the miR-432-5p promoter and elevates the expression of miR-432-5p in bladder cancer cells. The up-regulated miR-432-5p directly targets 3'-UTR and depresses RBM5 expression. Thus, RBM5-miR-432-5p-β-catenin forms a feedback loop in regulating bladder cancer cell apoptosis. Our findings provide evidence that the regulatory feedback loop among RBM5, miR-432-5p, and Wnt-β-catenin is responsible for the progress of bladder cancer cells.-Zhang, Y.-P., Liu, K.-L., Wang, Y.-X., Yang, Z., Han, Z.-W., Lu, B.-S., Qi, J.-C., Yin, Y.-W., Teng, Z.-H., Chang, X.-L., Li, J.-D., Xin, H., Li, W. Down-regulated RBM5 inhibits bladder cancer cell apoptosis by initiating an miR-432-5p/β-catenin feedback loop.

An isolated electron gun which could stably work at 500nA for more than 30 hours was proposed. The electron gun has a hybrid structure of multi-walled carbon nanotube (MWCNT) covered with Platinum tip. The gap between electrodes was adjusted by a nanomanipulation system to control the growth length and working distance inside a scanning electron microscope (SEM). About 374nm Platinum nanowire was in-situ growth in the tip of a single MWCNT with a precursor of cyclopentadienyl-trimethyl-platinum (IV) (CpPtMe3) to synthesized an electron gun. The working current stable at 500nA transferred from the tip of electron gun protected by the Platinum, with the working distance about 1 um, working voltage below 150V. It can work at a very low vacuum, it is about three orders of magnitude smaller than the vacuum required for a conventional gun. Moreover, the monitoring of SEM and the field emission characteristics shows that the electron gun has excellent stability during continue working which reached 50hours. The electron gun only consumed about 0.002um per working hour. The experimental result showed that the electron gun has broad application prospects in various field emission devices.

In this paper, based on the operating environment of scanning electron microscope (SEM), the cooperative control of carbon nanotubes by controlling multioperator hand was realized by controlling the robot operator with multiple degrees of freedom. Firstly, the carbon nanotube was picked up from the bulk by the nano manipulations. Then the nanotube was transferred on the surface of the metal electrode of the chip using the two nano manipulations and fixed on by electron beam induced deposition (EBID). In this robotics manipulation system, operation and assembly of carbon nanotube were successfully realized. The voltage-current property of the carbon nanotube was also evaluated in the SEM

Opinions on the nature and distinctiveness of the Chinese Paleolithic differ between those who assign early Late Pleistocene lithic technologies to some peculiar facies of the Middle Paleolithic, a...

Heterojunctions based on atomically thin p-type black phosphorus (BP) and n-type MoS 2 present their outstanding performance in electronic and optoelectronic devices. However, the relative weak photovoltaic characteristics offsets their advantages for high-performance phototransistors or solar cells. Herein, a plasmonic optical antenna arrays with 15nm gap were placed on the overlap regions of BP/ MoS 2 heterostructures for effective light-harvesting. The results demonstrate the photovoltaic characteristics of BP/ MoS 2 heterostructures is clearly enhanced through the hot electrons excited from optical antenna arrays under near-infrared laser $(\lambda=830\text{nm})$ . More important, this enhancement is mainly dominated by effective photo-carrier separation under higher built-in electric field at the reverse bias. In addition, the reduction of photocurrents at the forward bias is ascribed to the strong scattering from plasmon-induced heat. Our findings are expected to be valuable for the development of plasmon-enhanced photodetectors and photovoltaic devices.

Harvesting energy from ambient mechanical motions is an effective and feasible method for solving limitations of conventional batteries. In this article, a highperformance large-scale and flexible triboelectric nanogenerator (TENG) for harvesting ambient mechanical energy is demonstrated. It has many advantages, such as easy scalability, good flexibility, high performance and low cost. The TENG works at cycled contact-separation mode between polyethylene terephthalate (PET) and Cu film. The performance is remarkably improved by patterning microstructures on PET film. Power density of the TENG can reach to 0.47 mW/cm3. The power obtained from the TENG is capable of lighting up as many as 105 LEDs instantaneously.

This paper proposed the effective measurement method which combined macroscopic with microscopic inside the scanning electron microscope (SEM). It was put forward for the problem that in the measurement of trans-scale graphene materials, the small visual field of vision is in contradiction with the larger feature size span of the material. The local feature was extracted to measure the properties of trans-scale materials based on the nanorobotics manipulation system inside the SEM. The working environment with high vacuum and cleanness is provided in the SEM. In this experiment, the graphene material was fixed between the two golden grippers. The size was 2mmx2mm. It was stretched by nano-manipulators from 2 mm to 10 mm. Meanwhile., the surface structure of the graphene in nanoscale was observed in real time in the nano-robotics system under the SEM. In another experiment., the initial size of the material was 5mmx5mm and the graphene was stretched at a rate of 5% each time towards horizontal direction. The initial resistance was about 235 $k\Omega$ . by measurements. After some tensiles, the resistance was measured at about 575 $k\Omega$ The surface stretched micro structure could be observed clearly through the SEM. At the same time, the electrical characteristics of the material could be measured precisely.

The maneuvering and electrical characterization of nanotubes inside a scanning electron microscope (SEM) has historically been time-consuming and laborious for operators. Before the development of automated nanomanipulation-enabled techniques for the performance of pick-and-place and characterization of nanoobjects, these functions were still incomplete and largely operated manually. In this paper, a dual-probe nanomanipulation system vision-based feedback was demonstrated to automatically perform 3D nanomanipulation tasks, to investigate the electrical characterization of nanotubes. The XY-position of Atomic Force Microscope (AFM) cantilevers and individual carbon nanotubes (CNTs) were precisely recognized via a series of image processing operations. A coarse-to-fine positioning strategy in the Z-direction was applied through the combination of the sharpness-based depth estimation method and the contact-detection method. The use of nanorobotic magnification-regulated speed aided in improving working efficiency and reliability. Additionally, we proposed automated alignment of manipulator axes by visual tracking the movement trajectory of the end effector. The experimental results indicate the system's capability for automated measurement electrical characterization of CNTs. Furthermore, the automated nanomanipulation system has the potential to be extended to other nanomanipulation tasks.

This paper presented a series of cooperation strategies of symmetrically distributed multi-nanorobotic manipulators according to different tasks during nanodevice fabrication inside scanning electron microscopy (SEM). For constructing carbon nanotube (CNT) based nanodevice such as carbon nanotube field effect transistor (CNTFET), the mainly assembly processes implemented by different nanorobotic manipulators were discussed. Manipulation strategies for each task during assembly were established based on nanorobotic manipulation system. Experiments were designed and carried out to evaluate the effectiveness of different manipulation strategies designed for multi-task. The results shown that the designed manipulation strategies was adapted for the nanorobotic manipulation system during CNT based nanodevice assembly.

The emergence of the plasmid-encoded colistin-resistance gene mcr-1 in Enterobacteriaceae represents a new threat to the treatment of infection in the clinical setting. A sensitive and rapid molecular method for detection of the mcr-1 gene in clinical isolates is needed to control the spread of this gene. In this study, we established a loop-mediated isothermal amplification (LAMP) assay for rapid detection of the mcr-1 gene. This assay was applied to cultured bacteria and spiked human stools. Real-time monitoring of turbidity and chromogenic visualization were used to assess the reaction results. The specificity and sensitivity of the primers in the LAMP reactions for detection of the mcr-1 gene were determined. All 20 clinically resistant isolates without the mcr-1 gene tested negative, indicating the high specificity of the LAMP primers. The sensitivity of LAMP, with a detection limit of 0.2 pg/μL DNA, was 10-fold greater than that of polymerase chain reaction (PCR). The assay was also conclusive when applied to human stools spiked with mcr-1-positive Escherichia coli. During clinical screening in a major hospital in Beijing, China, seven isolates were identified as positive from the 556 Enterobacteriaceae isolates. In conclusion, the LAMP assay we developed was useful for detection of the mcr-1 gene in the clinical setting.

The parameters of synchronous generator used in power system are often obtained by the empirical formula. The simulation results calculated by these parameters have a large difference from the results of testing. Some people proposed that the accuracy parameters could be obtained by parameter identification base on experiment results. However, the large disturbance testing of large synchronous generator is hard to implement. Therefore, this paper proposes that the parameters are identified based on the results calculated by Time-Stepping Finite Element Model (T-S FEM). With a 300 MW turbine generator as an example, the steady-state parameters (x d , x q ), transient parameters (x d ', x q ', T d0 ', T q0 ') and sub-transient parameters (x d ", x q ", T d0 ", T q0 ") are identified by the least square method, and compared with the results by the empirical formula. The parameters are identified in different power angle and the influences factor on different parameters are compared and analyzed. Since the rotor slot wedge has several materials to choose from, the parameters of synchronous generator with slot wedge made from aluminum and stainless steel are identified respectively. The result shows that the parameters have a great difference in different power angle. The sub-transient time constants of synchronous generator with the rotor slot wedge made from stainless steel are smaller than that made from aluminum.

This paper presented a method of adopting carbon nanotubes with shorter length as vibrators to obtain higher mechanical quality factor. Two different lengths of MWCNTs were picked up through the van der Waals force between the AFM cantilever surface and MWCNT. The MWCNT was driven by the electrostatic force on its nature frequency. All these experiment were operated through a nanorobotic manipulation system with multiple positioning degrees of freedom (DOFs) inside the SEM specimen chamber. Two group of tests were carried out to obtain the Q values and resonance frequency of these two MWCNTs. We find that the Q values and resonance frequency of the longer MWCNT were higher than the shorter one. The Q values and resonance frequency of the longer CNT whose length is 10.91μm is 10.1 and 89KHz respectively while the Q values and resonance frequency of the shorter CNT whose length is 6.4μm is 69.6 and 985.4KHz.

Due to the dynamic load and the complex mechanical link, it is difficult to precisely analyze the characteristics of the energy consumption of Beam Pumping Motor Systems (BPMSs), in the development of energy saving approaches in oil production systems. To solve this problem, this paper establishes a practical model that combines the standard differential equation of induction motor, the crank movement equation and the wave equation of sucker rod, the loss equations of the low- and high-voltage supply lines and distribution transformers, for energy consumption analysis of BPMSs. With this practical model, the influence of different factors, including the load fluctuation, balance degree and dynamic liquid levels, on the electrical loss characteristics of BPMSs, can be analyzed. The variation of the electrical loss in a Type 12 BPMS driven by a 37kW induction motor with the different dynamic liquid levels and the balance degrees is studied, and the distribution characteristic of each loss component under five typical load conditions in oil field is also analyzed. It is revealed that the proportion of iron loss is about 40% of the total electrical loss. The correctness of the model is verified by comparing the calculated results with the measured data for a standard oil well. In addition, the energy saving devices based on the theoretical results obtained by the presented model achieve a significant energy saving ratio in the practical application at oil fields.

As an ideal method to manipulate biological particles, the dielectrophoresis (DEP) technique has been widely used in clinical diagnosis, disease treatment, drug development, immunoassays, cell sorting, etc. This review summarizes the research in the field of bioparticle manipulation based on DEP techniques. Firstly, the basic principle of DEP and its classical theories are introduced in brief; Secondly, a detailed introduction on the DEP technique used for bioparticle manipulation is presented, in which the applications are classified into five fields: capturing bioparticles to specific regions, focusing bioparticles in the sample, characterizing biomolecular interaction and detecting microorganism, pairing cells for electrofusion and separating different kinds of bioparticles; Thirdly, the effect of DEP on bioparticle viability is analyzed; Finally, the DEP techniques are summarized and future trends in bioparticle manipulation are suggested.

This paper presented a rotational electromagnetic energy harvester to scavenge the human kinetic energy and convert into electrical energy. The harvester simply introduced a cylindrical stator and disk-shaped rotor, which are made of NdFeB. Without complicated movement mechanism, the stator and rotor, of a higher pair have theoretical line contact by magnetic attractive force. Therefore, the rotor can easily rotate around the stator, avoiding unnecessary surface friction. In this paper, the wearable energy harvester was attached on human's ankle and wrist for harvesting body motion energy, such as jogging and running at different speeds. The relative movement between the fixed electromagnetic coil array and rotational magnetic rotor can generate electricity efficiently. At a running speed of 8 km/h, the maximum voltage and average power density can reach to 1.92 V and 0.2 mW/cm3, respectively. This rotational non-resonant energy harvester could be potentially used as alternative power source for smart wearable devices, such as wristwatch, heart-rate monitor, smart helmet and so on.

This paper presented a method for multiwalled carbon nanotube(MWCNT) and graphene fusion by applying current to the electric circuit system inside scanning electron microscopy (SEM). The MWCNT was picked up from CNT bulk and the graphene flake was exfoliated from graphite by nanorobotics manipulation system. The current was applied to the two ends of carbon nanotube and graphene. The C-C bonds at the end of the CNT and graphene were fused together. The theoretical tensile force and van der Waals force were about 166 nN and 30 nN. The method of this paper presented that the tensile force was about 20 nN before fusing the MWCNT and graphene. In contrast, the tensile force of fused carbon nanotube and graphene was about 90 nN and it was four times of the previous force.

With developments of micro-manipulation and micro-assembly, there is a growing demand for micro-grippers which are able to overcome the adhesion forces to pick up and release micro-objects effectively. This paper presents a separate-structured triple-finger gripper. Each finger is driven by piezoelectric (PZT) transducer. The gripper's end effectors are replaceable, so different end effectors can be used to adjust various targets with different shapes and sizes. The three fingers were assembled on an adjustable pedestal, so this gripper is able to achieve a precise clamping range. In the experiments, microspheres of different materials with diameters ranging from $10\ \boldsymbol{\mu} \mathbf{m}$ to $800\ \boldsymbol{\mu} \mathbf{m}$ were picked and released with more than 85% success rate. The applications of micro-assembly and super-resolution imaging were shown in the gripping experiments, which demonstrate important practical significance of this gripper. This triple-finger gripper has simple machining processes, high flexibility, and low cost.

Field-effect transistors (FETs) have been developed from silicon based to carbon nanotubes (CNTs) based, and the fabrication space became three-dimensionl (3D). Such fabrication process requires to accurately assemble a single CNT in 3D. However, most of the current assembly technologies were used for planar structures but not for 3D structures. In this study, we aim to use nanomanipulation based on a scanning electron microscopy (SEM) to realize the 3D assembly. To achieve this goal, we first proposed a novel 3D structure named Tri-gate CNT-FET. The Tri-gate CNT-FET has three cuboid micro-electrodes and it is wrapped by CNTs with front, top and back sides. After fabrication of the electrodes, a single CNT was picked up by an Au-coated probe and placed on the front side of the three micro-electrodes by suspending over a substrate to a certain height. The CNT pick-up and placement highly depended on attractive interactions at a CNT-metal contact interface by van der Waals force. Electron beam induced deposition (EBID) technique was then used to deposit Tungsten at the interface to fix CNT. Mechanical cutting was finally carried out to release the probe from the assembled structure. The whole assembly was achieved by using only one nanomanipulator. Experiment results validated our proposed 3D assembly method for the fabrication of Tri-gate CNT-FET.

Black phosphorus (BP), owing to its direct bandgap, has become one of the most competitive candidate for photodetectors. In this report, the I-V characteristics of BP field-effect transistors (FETs) is measured for the first time. The photo-response time (including both the rise and fall time) of multilayer black phosphorus photodetectors is then explored and the feature of photocurrent signals is discussed under an infrared laser beam (λIR = 830nm) in details. Our experimental results reveal that due to photovoltaic effect in the off-state of the BP FETs, a rise time below 6ms and a fall time below 23ms have been obtained; demonstrating very fast response of black phosphorus photodetectors. These are promising for the applications of BP-based FETs as ultra-fast optoelectronic devices.

This paper presented a method for multiwalled carbon nanotubes (MWCNTs) fusion induced by electron beam irradiation inside scanning electron microscopy (SEM). The MWCNT was picked up from CNT bulk by nanorobotics manipulation system. The electron beam irradiation was introduced at the joint of two free end of MWCNTs. C-C bonds at the ends of CNTs were fused together. The method of this paper presented that before fusion the tensile force of the junction was about 20 nN before fusion, however, the tensile force of fused muliwalled carbon nanotubes was about 100 nN. The tensile force of fusion MWCNTs reached 70 percent of the original MWCNT's.

This paper presents a triple-finger gripper driven by a piezoceramic (PZT) transducer for multi-target micromanipulation. The gripper consists of three fingers assembled on adjustable pedestals with flexible hinges for a large adjustable range. Each finger has a PZT actuator, an amplifying structure, and a changeable end effector. The moving trajectories of single and double fingers were calculated and finite element analyses were performed to verify the reliability of the structures. In the gripping experiment, various end effectors of the fingers such as tungsten probes and fibers were tested, and different micro-objects such as glass hollow spheres and iron spheres with diameters ranging from 10 to 800 μm were picked and released. The output resolution is 145 nm/V, and the driven displacement range of the gripper is 43.4 μm. The PZT actuated triple-finger gripper has superior adaptability, high efficiency, and a low cost.

With the progress of nanotechnology and the development of micro electro mechanical system which makes it possible to manufacture high precision micro and nano level vibration based sensors. The purpose of this paper is to provide a brief overview of study on the study on vibration characteristics of carbon nanotubes such as resonance frequency and quality factors which have a great influence on the application of the CNTs. We also discussed the application of the Vibration of Carbon Nanotubes. We conclude with a look at the future of the Study on Vibration Characteristics of Carbon Nanotubes and more application of the CNT resonators.

This paper presented a method of adopting Pt/MWCNT nanowire as a vibrator which is used to increase the quality factors of the MWCNT. A platinum nanowire growth was induced via the EBID method from a carbon nanotube (CNT) emitter with a trimelyl cyclopentadienyl platinum (CpPtMe3) precursor. The MWCNT was driven by the electrostatic force on its nature frequency. Two groups of experiments were carried out. We find that the Q value is increased and the resonance frequency was decreased after the growth of high-purity platinum on the tip of a MWCNT. The Q value of the Pt/MWCNT is 20.2 which is larger than the MWCNT without Pt whose Q value is 10.1. For the resonance frequency, the value of the Pt/MWCNT is 57 KHz which is smaller than the MWCNT whose value is 89 KHz.

It is of great importance to pick up a single carbon nanotube (CNT) from a bulk of CNTs for nanodevice fabrication. In this study, we have proposed a nanorobotic manipulation system allowing automated pick-up of CNTs based on visual feedback. We utilize histogram normalization for automatic binarization, and it achieves to clearly distinguish CNTs from substrate and other impurities under different image brightness. Furthermore, we develop the gradient orientation inversion (GOI) algorithm to recognize CNT tip and atomic force microscopy (AFM) cantilever. Taking full advantages of the geometrical characteristics of CNT and AFM cantilever, GOI is proved to be quite robust. We have designed segment detection method (SDM) to successfully separate the AFM cantilever and CNT, whereas the contact detection between them is achieved by analyzing the straightness variation. Preliminary experimental results imply that our method shows high promise in realistic fabrication of nanodevices.

Carbon nanotubes (CNT) have been developed in recent decades for nanodevices such as nanoradios, nanogenerators, carbon nanotube field effect transistors (CNTFETs) and so on, indicating that the application of CNTs for nanoscale electronics may play a key role in the development of nanotechnology. Nanorobotics manipulation systems are a promising method for nanodevice construction and assembly. For the purpose of constructing three-dimensional CNTFETs, a nanorobotics manipulation system with 16 DOFs was developed for nanomanipulation of nanometer-scale objects inside the specimen chamber of a scanning electron microscope (SEM). Nanorobotics manipulators are assembled into four units with four DOFs (X-Y-Z-θ) individually. The rotational one is actuated by a picomotor. That means a manipulator has four DOFs including three linear motions in the X, Y, Z directions and a 360-degree rotational one (X-Y-Z-θ stage, θ is along the direction rotating with X or Y axis). Manipulators are actuated by picomotors with better than 30 nm linear resolution and

In this paper, a nanorobotics manipulation system with 16-DOF was constructed for 3D nanomanipulation of nanometer-scale objects inside a specimen chamber of the scanning electronic microscopes (SEM). Nanorobotics manipulators were divided into 4 units. Each unit was comprised of a X, Y, Z stage (Sigma, TSDS-255C), 4 Picomotors and an atomic force microscope (AFM) cantilever (Olympus, OMCL-TR400PB-1). Each manipulator has 4-DOF with 3 linear motions in X, Y, Z directions and a 360-degree rotational one (X-Y-Z-θ stage, θ is along the direction rotating with X or Y axis). Manipulators were actuated with picomotors with better than 30 nm linear resolution and

A method of assembling a multi-walled carbon-nanotube field effect transistor (CNT-FET) was presented in this paper. A nanorobotic manipulation system with 11 positioning degrees of freedom (DOFs) was used for the real time nanomanipulation. The nanorobotic manipulation system was constructed inside the scanning electron microscopy (SEM) specimen chamber to pick up a single MWCNT from MWCNT bulk without any other bounding except van der Waals force and assemble a CNT-FET with three AFM cantilevers, which were applied as gate, drain, source of CNT-FET respectively. An AFM cantilever (Olympus, OMCL-TR400PB-1) was etched to a gate electrode with a width of 2.00 µm and a length of 8.30 µm by a focused ion beam (FIB) process. A single multi-walled carbon-nanotube field (MWCNT), 51 nm in diameter, was used as conductive channel to accomplish the transport process of charge carriers between Source and Drain. Finally, a novel structure of CNT-FET was constructed in our experiments.

A method of making copper particles melting into mutil-wall carbon nanotube (MWCNT) will be presented in this paper. A nanorobotic manipulation system with multiple positioning degrees of freedom (DOFs) was used for the real time nanomanipulation. The nanorobotic manipulation system was constructed inside the scanning electron microscopy (SEM) specimen chamber to pick up MWCNT from MWCNT bulk without any other bounding except van der Waals force and measure the electrical properties of MWCNT and MWCNT/Cu hybrid nanowire. The electron beam was focused on a copper particle cluster of about 200 nm diameter, under SEM. After 5 minutes of electron beam focusing, the melting Cu started to climb into the MWCNT along the wall of the MWCNT. The electrical properties of MWCNT and MWCNT/Cu hybrid nanowire were measured through the model 4200 semiconductor characterization system (4200-SCS). Finally, the electrical properties of MWCNT and MWCNT/Cu hybrid nanowire were plotted on the I-V curves.

This paper proposed an effective release method of micro objects by adhesion control based on the piezoelectric vibration. A micromanipulation system was presented to carry out dynamic manipulation. The operation strategy employing inertia force to overcome adhesion force was established by modeling and theoretical analysis. Experimental results with this release method achieved 90% repeatability with releasing accuracy of 4± 0.5µm, which was experimentally quantified through the manipulation of 20–80µm polystyrene spheres under an optical microscope. A novel triple-fingers gripper device was designed to achieve a perfect release effect. Tungsten tipped probes as the finger of end effectors were used to pick and place the micro objects. The probes were mounted on three cantilevers driven by piezoelectric ceramic transducers (PZT). 200 spheres had been picked up and placed on the platform. The experiment results shown that, with the help of releasing probe, the spheres of 20µm size could be released in 1s per time.

This paper presented a method of picking up carbon nanotubes (CNTs) from nanotube bulk by van der Waals force between the carbon nanotubes and AFM cantilever under scanning electron microscopy (SEM). A manipulation strategy was established based on SEM by analyzing the van der Waals force of three different types of contacting model. Three groups of experiments were designed and carried out to investigate the effects of different factors which conclude pickup angle, pickup contact area between the carbon nanotube and the cantilever and pickup speed of the end-effector. The results shown that a pickup angle at 90.1° and a pickup speed at 10nm/step with a pickup contact length more than 1.5µm would increasing the probability of picking up CNT successfully.

A series of cobalt-free perovskite-type cathode materials La0.6Sr0.4Fe1–xNixO3–δ (0 ≤ x ≤ 0.15) for intermediate temperature solid oxide fuel cells (IT-SOFCs) are prepared by a citric-nitrate process. The conductivities of the cathode materials are measured as functions of temperature (300–800 °C) in air by AC impedance method, and the La0.6Sr0.4Fe0.9Ni0.1O3–δ (LSFN10) has the highest conductivity to be 160 S cm–1 at 400 °C. A single IT-SOFC based on LSFN10 cathode, BaZr0.1Ce0.7Y0.2O3–δ electrolyte membrane and Ni–BaZr0.1Ce0.7Y0.2O3–δ anode substrate was fabricated by a simple spin-coating process, and the performances of the cell using hydrogen as fuel and air as the oxidant were researched by electrochemical methods at 600–700 °C. The maximum power densities of the cell are 405 mW cm–2 at 700 °C, 238 mW cm–2 at 650 °C, and 140 mW cm–2 at 600 °C, respectively. The results indicate that the LSFN10 is a promising cathode material for proton conducting IT-SOFCs.