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The robustness of electrostatic sensitive devices is important in state-of-the-art silicon technology. However, the electrical breakdown-induced microstructure evolution remains unclear. In this work, we performed the physical failure analysis of breakdown in an enhanced modified lateral silicon-controlled rectifier-based electrostatic discharge (ESD) device. Direct visualization of the conductive metal filaments in the doped silicon substrate has been achieved by high-resolution transmission electron microscopy. The locations of these metal filaments induced by breakdown are found near the cathode. The evolution of these microstructural changes and chemical properties provides guide to the failure analysis of ESD devices.

Security response centre (SRC) is an important solution for enterprises to ensuring their network security. The existing security response centres can be mainly divided into two types, the third-party vulnerability reporting platforms and xSRCs of each enterprise. Normally, hackers find and submit valuable information to a vulnerability reporting platform or xSRC. However, the hackers who submit vulnerabilities probably disagree with the assessment results of vulnerability level by enterprises or the third-party platform experts entrusted by enterprises, which may lead to some dangerous situations that can threat the enterprise’s network security. This paper proposes a security intelligence trading platform based on blockchain and IPFS (Inter Planetary File System), and applies it to a specific example. Due to the decentralization and immutability of blockchain technology and IPFS, it can make the vulnerability level assessment fair and just, which will protect the interests and privacy of both hackers and enterprises. The example proves that the proposed method is simple and feasible, and has theoretical and practical value to the exploration of security information transaction mechanism.

The ultrastable metal electrodes that can withstand the mechanical deformations of the soft substrates are always essential for the development of flexible supercapacitors. However, the metal electrode physically deposited on the flexible substrate is rigid and delaminated, and the contact interface is easily degraded under the mechanical cycling. The highly flexible and conductive composites with the intermixed metal–polymer structure as electrodes are key to solving the contact problem. In this work, a universal and facile method for flexible micro-supercapacitors (MSCs) with combination of nickel electroless plating (EN) and reduced graphene oxide (rGO) electrodeposition was presented. The so-called surface exchange and ion exchange (SMIE) technique has been employed to prepare the seed layer, and the electroless plating was conducted to deposit the Ni–P layer. The rGO-coated (GC) layer was then electrodeposited onto the Ni–P layer to form an EN/GC composite structure. EN/GC electrodes with symmetric i...

International audience; The high intrinsic carrier mobility of graphene has drawn much attention. However, the high contact resistance between the graphene and metal electrode limits the application of high-speed graphene-based transistors. In this work, we combined both electrical characterization and Raman spectroscopy to study the contact resistance issue in graphene field effect transistor (FET). As FET size scaling down, the graphene-metal contact resistance is found to be a significant contributor to the total resistance. The signature of the graphene/metal bonding with various metal electrodes is probed by using high-resolution Raman spectroscopy. Graphene-metal Raman signals vary on different metal electrodes. This study unearths the properties of the graphene/metal bonding, and paves a way for the investigations into improving the stability and scalability of the graphene-based transistor for future high-speed nanoelectronics.

Metallic two-dimensional (2D) 1T-VSe2 with high conductivity and a large specific surface area is a promising electrode material for supercapacitors. Here, we use a facile chemical vapor deposition (CVD) method to prepare thin VSe2 nanosheets. A flexible in-plane solid-state supercapacitor is fabricated using the high-quality VSe2 nanosheets as the electrode material. The prepared supercapacitor presents an electrical double-layer capacitive behavior, and it has a high power density that is comparable with that of advanced graphene-based supercapacitors. The flexible supercapacitor also shows good mechanical stability to both bending and fatigue tests up to 10 000 cycles. This work provides a novel method for the fabrication of high-performance thin-film power sources, and paves the way for their application in soft thin-geometry devices.

Mechanical flexible electronic skin has been focused on sensing various physical parameters, such as pressure and temperature. The studies of material design and array-accessible devices are the building blocks of strain sensors for subtle pressure sensing. Here, we report a new and facile preparation of a graphene hybrid structure with an ultrafast dynamic pressure response. Graphene oxide nanosheets are used as a surfactant to prevent graphene restacking in aqueous solution. This graphene hybrid structure exhibits a frequency-independent pressure resistive sensing property. Exceeding natural skin, such pressure sensors, can provide transient responses from static up to 10 000 Hz dynamic frequencies. Integrated by the controlling system, the array-accessible sensors can manipulate a robot arm and self-rectify the temperature of a heating blanket. This may pave a path toward the future application of graphene-based wearable electronics.

Alloying is critical for regulating the electron states of layered two-dimensional (2D) materials, which has a significant influence on the physical and chemical properties of 2D materials, such as electrochemical catalysis, magnetism, and the bandgap of semiconductors. Here, we report the alloy of Fe-doped VSe2 with good homogeneity at the atomic level by using a one-step synthesis method. Fe-doped VSe2 presents enhanced hydrogen evolution reaction (HER) performance. It is found that Fe-doped VSe2 shows improved catalytic activity compared to the virgin VSe2, including a lower overpotential and a smaller Tafel slope. The enhanced HER performance indicates a lower Gibbs free energy of the HER process, resulting from the doping-induced regulation of the electron states. Our work presents a facile method to prepare transition metal-doped 2D materials and offers a general way to regulate the catalytic properties of 2D materials for energy conversion applications.

In situ transition electron microscopy (TEM) with its high-resolution imaging and analytic capability is playing an essential role in characterization and manipulation of nanoscale devices. This review article focuses on the application of in situ TEM in a wide range of advanced electronic devices for both fundamental physics study and real-time manipulation. These devices include transistors and non-volatile memory consisted of resistive random access memory, phase change memory, and ferroelectric resistive random access memory. We will show how in situ TEM is powerful in examining the structural evolution, change in chemical component, and devices reliability in atomic scale and real time.

Two-dimensional (2D) transition metal dichalcogenides alloys are potential materials in the application of photodetectors over a wide spectral range due to their composition-dependent bandgaps. The study of bandgap engineering is important for the application of 2D materials in devices. Here, we grow the Mo1−x W x Se2 alloys on mica, sapphire and SiO2/Si substrates by chemical vapor deposition (CVD) method. Mo1−x W x Se2 alloys are grown on the mica substrates by CVD method for the first time. Photoluminescence (PL) spectroscopy is used to investigate the effects of substrates and interlayer coupling force on the optical bandgaps of as-grown Mo1−x W x Se2 alloys. We find that the substrates used in this work have an ignorable effect on the optical bandgaps of as-grown Mo1−x W x Se2. The interlayer coupling effect on the optical bandgaps of as-grown Mo1−x W x Se2 is larger than the substrates effect. These findings provide a new way for the future study of the growth and physical properties of 2D alloy materials.

Wearable electronic sensing devices are deemed to be a crucial technology of smart personal electronics. Strain and pressure sensors, one of the most popular research directions in recent years, are the key components of smart and flexible electronics. Graphene, as an advanced nanomaterial, exerts pre-eminent characteristics including high electrical conductivity, excellent mechanical properties, and flexibility. The above advantages of graphene provide great potential for applications in mechatronics, robotics, automation, human-machine interaction, etc.: graphene with diverse structures and leverages, strain and pressure sensors with new functionalities. Herein, the recent progress in graphene-based strain and pressure sensors is presented. The sensing materials are classified into four structures including 0D fullerene, 1D fiber, 2D film, and 3D porous structures. Different structures of graphene-based strain and pressure sensors provide various properties and multifunctions in crucial parameters such as sensitivity, linearity, and hysteresis. The recent and potential applications for graphene-based sensors are also discussed, especially in the field of human motion detection. Finally, the perspectives of graphene-based strain and pressure sensors used in human motion detection combined with artificial intelligence are surveyed. Challenges such as the biocompatibility, integration, and additivity of the sensors are discussed as well.

Two-dimensional (2D) metallic transition-metal dichalcogenide (MTMD)/carbon-nanotube (CNT) compounds are competitive electrode materials for solid-state flexible in-plane supercapacitors, resulting from the synergistic effect of the large specific surface area of 2D MTMDs and the excellent mechanical properties of the CNT. In this paper, the high-quality VSe2/CNT electrode material is prepared by the one-step chemical vapor deposition (CVD) method. The CVD method offers a facile and safe way to synthesize a pure VSe2/CNT compound. The VSe2 nanosheets are vertically grown on the surface of the CNT cluster. The vertical configuration of the VSe2 nanosheets on the conductive CNT cluster takes full advantage of the large specific surface area of the VSe2 nanosheets to store charges. The ductile and conductive CNT cluster offers good mechanical and electrical connections to the VSe2 nanosheets. The VSe2/CNT compound is applied as the electrode material of a solid-state flexible in-plane supercapacitor which achieves a specific area capacitance of 1854 μF/cm2 and stable cycling stability, ∼7% degradation after 10 000 times of current cycling. The VSe2/CNT also presents a desirable mechanical stability, and ∼ 90% capacitance is retained after bending up to 40°. This work promotes the application of 2D MTMD compounds in the field of energy storage and wearable devices.

The sliding formwork construction is a new technology of cast-in-place concrete project, com-pared with the conventional construction method, synovial fast construction speed, high degree of mechanization, can save formwork and scaffold required quantity, can be more convenient and flexible template apart will be assembled and can be reused. The article for a new kind of reinforced concrete structure, form of syn-ovial membrane were discussed in detail, and has carried on the analysis to its application in construction. 1 Sliding mode structure described 1.1 The technical background The cast-in-place concrete structure engineering for construction of building template structure, mainly composed of a panel, the supporting structure and the connecting piece is composed of three parts. The panel is in direct contact with the bearing plate of fresh concrete; support structure is the temporary structure support panel, concrete andconstruction load, guarantee the structure building templates are firmly combined, do not deformation, not destroy; the connecting piece is connected into the panel and the supporting structure parts of the whole. The fixed template in building construction, not only cost is high, and the disassembly and assembly are the need of professionals, and spend a lot of manpower and resources,increase the cost of the project, to extend the time limit for a project, is not conducive to the development of modern construction industry. 1.2 The content and structure The technical problem of reinforced concrete sliding mode to solve, is to address the above problems of technology, provides a special reinforced concrete sliding mode, a baffle andenclosure fixed form templates, Jack in jack frame along the rod climbing movement, thereby driving the construction template rises, cancel the fixed template, fixed template for slip type movable steel die, so do not need to prepare a large number of fixed template erection. In order to solve the technical problem, the technical scheme adopted is: synovial includingjack, jack frame, pole climbing and template, two horizontal fixed jack frame on both sides are respectively provided with two templates, and the template plane perpendicular to the jackframe is fixed; Jack is fixed on the joists center position, stringer is horizontally arranged in thejacks frame; the pole climbing vertical penetrating beam jack frame, and pole climbing through the stringers and jack fixed; two jacks and a high pressure oil pipe in series, the other end of the high pressure oil pipe connected with the fuel line of the high-pressure fuel pump; the lower end part of the climbing rod is fixedly provided with a supporting plate, a supporting plate in the length direction and jack plane vertical. Jack comprises a lifting column and cylinder, cylinder and pole climbing through after lifting column fixation. The template includesenclosure and a baffle, the baffle is installed on the upper and lower ends outside theenclosure, and the baffle plate and the enclosure is vertical to the length direction. The baffle plate and the enclosure are connected through a stud and nut, the baffle plate are arranged on the inner side of the nut hole. Compared with the prior art, the synovial membrane has the following advantages: 1, Jack injack 5th International Conference on Information Engineering for Mechanics and Materials (ICIMM 2015) © 2015. The authors Published by Atlantis Press 1623 frame along the rod climbing movement, so as to enhance the template increases in height, has changed the traditional fixed template, inefficient construction need to re disassembly can re construction; 2, high-pressure tubing and two jack oil road series,ensuring the work when the template is also rising, to prevent the occurrence of the phenomenon of high-low plate, speed up the construction progress; 3, the baffle plate are arranged on the inner side of the nut in the hole position, the nut just into the nut holes,reduces the friction and avoid the emergence of baffle baffle concave convex surface. 1.3 Sliding mode structure design 2 Application method in construction 2.1The construction scheme of the multi-storey residential building Combined with last picture, including a jack, jack frame 2, 3 and templates climbing pole 4, two horizontal fixed jack stand two sides were fitted with two templates 4 and 4 template plane perpendicular to the jack frame 2 fixed; jack a fixed position in the beam centered on five, five horizontal beams mounted in the jack stand 2; 3 vertical pole climbing frame beams 2 through 6 jacks and climbing pole 3 through 5 and the jack a stringer fixed; two jack 1 in series with a high-pressure tubing 7, high-pressure tubing and the other end with the high pressure pump 8 is connected to an oil passage 7; the lower end portion of the rod 3 is fixed climbing support plate 9 is mounted, support plate 9 and the jack frame 2 in the plane perpendicular to the longitudinal direction ; jack 1 includes lifting column 10 and cylinder 11, after climbing pole 3 through 11 with the lifting cylinder 10 is fixed to the column; 4 includes templates baffle enclosure 12 and 13, the upper and lower ends of the outer flaps 13 are mounted enclosure 12, and baffle enclosure 13 and 12 in the longitudinal direction perpendicular; baffle 13 12 15 connected with the enclosure through the studs and nuts 14, 13 have a nut inside of the bezel opening 16 holes. High-pressure pump 8 through the high pressure hydraulic hose 7 to jack a job, a jack lifting column on the drive lever 3 climb downward movement of the cylinder 11 due to the stringers 5 fixed cylinder 11 to drive along the climbing frame 2 jack up rod 3 sports, installation will reach 9 supporting role in the bottom of the climbing pole three gussets in the cement wall 17, thereby ensuring a template 4 remains horizontal, template 4 by baffles 13 and 12 around the circle with 14 studs and nuts 15 composed of the baffle 13 holes opened a nut 16, reducing the template 4 and 17 cement

This article introduces a kind of reinforced concrete hollow pillar, the pillar with hollow beam and column composed of reticular cells, each mesh cell in the horizontal direction through the telescopic column connection, in the vertical direction through the internal screw sleeve connection, terminal in the reticular cells in horizontal direction through the elbow connection pipe is connected with the telescopic rod is matched by a positioning pin through, upright positioning hole on the pin connected with the template. The pillar of reticular cells can be combined arbitrarily in the horizontal direction and the vertical direction, the hollow pillar according to the construction size requirements to good combination reticular cells form, with the template will be pouring concrete inside the template, can be installed through the lifting device at the top of the upright post of the whole mechanism to lift the mobile, reduced the construction equipment covers an area of, shorten the building time, easy to move, can complete the construction without support. At the same time, through the contrast calculation, the pillar of compressive bearing capacity calculation formula of good, can be extended.

Poly(vinylidene fluoride-trifluoroethylene-chlorofloroethylene) terpolymer films have been fabricated on Al-coated polyimide substrates using the Langmuir–Blodgett (LB) technology. The electrical properties of the films have been investigated from 150 to 350 K. The temperature of the dielectric maximum and the measured frequency obeys the Vogel–Fulcher [J. Am. Ceram. Soc. 8, 339 (1925); Phys. Z. 22, 645 (1921)] law. The electric tunabilities of the films at room temperature are 42.6% and 80% under 50 and 240 MV/m, respectively. The reasons for the high tunability are discussed based on the special microstructure of the LB films.