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Precision physical quantity of sensing using ensembles of nitrogen vacancy (NV) centers in diamond has attracted wide interest in recent years. A widely studied prototype is a micron-sized diamond crystal mounted on a fiber tip which forms a scanning vectorial sensor for temperature, magnetic/electric field in the study of fundamental phenomena in condensed matter physics, bio-science and electromagnetics. A general issue in this application is the determination of the crystal orientation in the lab coordinate. In this work, we propose a practical method using an orthogonal 3-axis coil to determine the relative orientation of crystal in the coordinate of the coil (lab-frame coordinate). The transformational relation between the lab-frame coordinate and the NV body frame coordinate is established with the data of the optically detected magnetic resonance (ODMR) spectrum peak shifts and applied magnetic field vector. We demonstrate tunable RF field sensing using this micrometer sized probe, the proposed method is expected to find field imaging applications with frequency ranging from microwave to millimeter wave.

In this paper, a noninvasive quantum imaging method of the near-field (NF) distribution of patch antenna was proposed by using a diamond containing nitrogen-vacancy (NV) centers. We applied AM/FM pulse modulation technique combined with optical detection magnetic resonance to measure the microwave magnetic field of a patch antenna. A full reconstruction formulation of the magnetic field vector, including the amplitude and phase, is proposed by measuring both the left and right circular polarizations along the four NV axes. Furthermore, we proposed a novelty method to reconstruct the surface current distribution imaging of patch antenna by using an integral equation based on magnetic field. The proposed quantum imaging method can directly measure the NF distribution of real antenna. Compared with HFSS simulation, the microwave imaging experiment is sensitive to actual manufacturing details such as the metal cross section due to etching and dielectric layers such as solder masks and shows the microwave field distribution of the real antenna. A nanoscale diamond probe enables nanoscale high-resolution imaging. The proposed method is expected to have applications in diagnosis on monolithic microwave integrated-circuits chip, antenna characterization, and the field mode imaging of nanoscale semiconductor radio frequency devices.

High-resolution field imaging with minimized invasiveness is of growing interest with the development of radio frequency (RF) integrated circuits and planar antenna characterization. In this paper, we propose an optical broadband sensor with static offset magnetic field using a diamond crystal that contains an ensemble of nitrogen-vacancy (NV) centers. The spatial resolution of micrometer scale is demonstrated by using a diamond crystal of this size. This technique is based on the modulation of fluorescence emitting by NV center under green laser excitation, by an off-axis magnetic field at radio frequencies. We demonstrate experimentally the detection of an RF magnetic field, with minimum measurable amplitude on the order of 0.1 Gauss, which is limited by the noise floor of the avalanche photodetector. The sensitivity can be further improved by noise suppression in optics. The bandwidth of the sensor is measured to be 15 MHz.

Modal parameter model acts as an analytical model of tire, because it can represent the entire tire characteristics, when applied to the tire modelling. However, without considering the effect of transfer characteristics of adjacent tread spring elements, the accuracy of modal parameter model may be limited in previous studies. Based on contact mechanics and the modal parameter model, a novel tread model is proposed considering tread transfer characteristics, and then a modified model using the modal parameters was obtained using the novel tread model. The effects of tire external characteristics were analyzed by modifying the modal parameter static vertical model. Finally, the experimental and calculated data were compared, the proposed tread model improved the accuracy of calculation. The results show that the tread transfer characteristics significantly affect contact length, i.e., by improving the predictive accuracy by 50 %, and the effect on improving the squat of tire can be ignored. The developed model may help to optimize tire modelling.

Chip-level EMC testing and diagnostic analysis technology plays an important role in the design and development of highly integrated microwave and millimeter-wave chips. In this paper, an all-optical and non-invasive microwave magnetic field scanning probe system based on diamond NV color centers is constructed, with RF B-field sensitivity of 5 nT/√Hz and spatial resolution smaller than 10 micron. The frequency tuning from DC to 100 GHz magnetic resonance can be achieved by Zeeman splitting technique. Full vector reconstruction of microwave near field can be realized with its four crystal axis. The current distribution on the surface of the microchip under test can be deduced by the quantum magnetic field inverse radiation problem solver. The EMC problem on the chip surface can be further analyzed by the current distribution on the chip surface. The experimental system built in this paper verifies the feasibility of the system by microwave near-field imaging of a GaAs MMIC low-pass filter chip with 3dB cut-off frequency of 6GHz.

We present a microwave B-field scanning imaging technique using a diamond micro-crystal containing a nitrogen vacancy center that is attached to a fiber tip. We propose a pulsed modulation technique, enabling the implementation of a variety of pulsed quantum algorithms for state manipulation and fast readout of the spin state. A detailed mapping of the magnetic B-field distribution of a helical antenna with sub-100 μm resolution is presented and compared with numerical simulations. This fiber based microwave B-field probe has the advantages of minimized invasiveness and small overall size and will boost broad interest in a variety of applications where near field distribution is essential to device characterization, to name a few, antenna radiation profiling, monolithic microwave integrated circuit failure diagnosis, electromagnetic compatibility test of microwave integrated circuits, and microwave cavity field mode mapping.

In order to obtain the force of the foot of a multi-foot robot, a new type of structure based on the sliding axis is proposed. [1] This structure is improved based on the traditional cross beam six-dimensional force sensor. The structural characteristics of the sensor and the principle of force measurement are analyzed. Static and dynamic simulation of the elastic body is carried out by using the finite element method. The deformed cloud, strain cloud, mode shape and natural frequency of the elastic element are obtained. According to the result of finite element analysis, the position of the patch is simulated in the three-dimensional model, and the elastic element of the sensor is decoupled and linearity analyzed. Finally, the calibration matrix of the sensor is obtained.

The transmission gear is taken as the research object in this paper, the high damping alloy material is added to the gear to attenuate the vibration when the gears meshes. First, the gear transmission with damping alloy is compared with the traditional gear transmission through the rigid-flexible coupling model in ADAMS, and then the change of gear center acceleration during transmission is analyzed. The damping effect of the high-damping alloy material verifies that the increase of the gear damper can attenuate the vibration, and more effective in high-frequency transmission.

In this paper, a HVAC assembly for a domestic automotive air conditioner is studied. The 3D modeling and fluid simulation of the HVAC assembly are carried out. The flow of the gas-solid two-phase flow in a certain concentration of PM 2.5 is studied, including the velocity distribution of the upper surface of the filter element and the trajectories of the internal fluid and particles are analyzed. According to the simulation results, the unreasonableness of the existing HVAC assembly structure is found and the optimization suggestion is put forward.

A silicon surface with distinctive structures is fabricated by ultrashort pulsed-laser ablation and chemical etching with acidic fluoride solutions. The surface consists of micro/nanostructures that result in the quasi-superhydrophobicity of the silicon surface. By fine tuning a key process parameter (i.e., pulsed laser power), surfaces with different wettability are fabricated. The morphology and composition of the surfaces are characterized by scanning electron microscopy, which reveals nanopores. The contact angle of water on these surfaces was measured and found to be as high as 150° at optimized parameters. This work presents a novel process of fabricating a silicon-based quasi-superhydrophobic porous surface.

The synthesis and determination of the crystal structures of eight mixed-ligand divalent coordination polymers based on 3,5-diiodobenzoic acid (HL) and ancillary nitrogen ligands (bpy = 4,4′-bipyridine, bpe = 1,2-bis(4-pyridyl)ethene, p-bix = 1,4-bis(imidazol-1-ylmethyl)-benzene, bpp = 1,3-bi(4-pyridyl)propane, bbi = 1,1′-(1,4-butanediyl)bis(imidazole), namely, [Zn(L)2(p-bix)]n (1), [Zn3(L)6(bpp)]n (2), [Cd1.5(L)3(bpp)]n (3), [Ni(L)2(bpe)·H2O]n (4), [Co(L)2(p-bix)]n (5), [Co1.5(L)3(bpy)0.5]n (6), [Mn3(L)6(bpe)]n (7), and [Mn3(L)6(bbi)]n (8), have been reported. They were well characterized by elemental analysis, IR spectra, and single crystal X-ray diffraction. Compounds 1–5 all exhibit three-dimensional (3D) supramolecular structures based on interchain type II I···I halogen bond interactions, or hydrogen bonding and type I I···I contacts, respectively. Moreover, π···π interactions are found in the structure of 3. In compounds 6–8, similar two-dimensional (2D) metal–organic layers are expanded to 3D supr...

We propose a diamond-based micron-scale sensor and perform high-resolution B-field imaging of the near-field distribution of coplanar waveguides. The sensor consists of diamond crystals attached to the tip of a tapered fiber with a physical size on the order of submicron. The amplitude of the B-field component B is obtained by measuring the Rabi oscillation frequency. The result of Rabi sequence is fitted with a decayed sinusoidal. We apply the modulation-locking technique that demonstrates the vector-resolved field mapping of the micromachine coplanar waveguide structure (CPW). B-field line scan was performed on the CPW with a scan step size of 1.25 μm. To demonstrate vector resolved rf field sensing, a full field line scan acts (was performed) along four NV axes at a height of 50 μm above the device surface. The simulations are compared with the experimental results by vector-resolved measurement. This technique allows the measurement of weak microwave signals with a minimum resolvable modulation depth of 20 ppm. The sensor will have great interest in micron-scale resolved microwave B-field measurements, such as electromagnetic compatibility testing of microwave integrated circuits and characterization of integrated microwave components.

A series of copper coordination polymers of [Cu3(OH)2(5-iipa)2(phen)3(H2O)·4.5(H2O)]n (1) [Cu(5-iipa)(phen)(H2O)]n (2), [Cu(5-iipa)(bpe)·2(H2O)]n (3), [Cu(5-iipa)(p-bix)]n (4), [Cu(5-iipa)(bbi)]n (5), [Cu2(5-iipa)2(bbi)·0.5(H2O)]n (6), and [Cu(5-iipa)(bpp)·H2O]n (7) (phen = 1,10-phenanthroline, bpe = 1,2-bis(4-pyridyl)ethane, p-bix = 1,4-bis(imidazol-1-ylmethyl)-benzene, bbi = 1,1′-(1,4-butanediyl)bis(imidazole), bpp = 1,3-bi(4-pyridyl)propane) were hydro(solvo)thermally synthesized through the reaction of divalent copper salts, 5-iodo-isophthalic acid (5-H2iipa), and N-donor ancillary ligands. Single-crystal X-ray diffraction analyses on these complexes revealed that noncovalent interactions were found to be predominant in constructing these supramolecular architectures. Compounds 1–5 all possess three-dimensional (3D) supramolecular structures based on O···I, I···I, I···π, and π···π interactions. Compound 6 exhibits a complicated three-dimensional (3D) framework with a new (6·72)2(63·72·8)2(63·78·82·92)...

A polar homochiral 3D MOF [{Co2(L)(bpe)(H2O)}·5H2O]n constructed with cobalt(II) and a new ligand N-(1,3-dicarboxy-5-benzyl)-carboxymethylglycine (H4L) accommodates ordered helical water streams in its helical grooves. It provides the first example of switchable ferroelectric and optical behavior through two-step reversible single-crystal to single-crystal transformation (SCSC) upon desorption/adsorption of water spirals and coordinated water molecules, respectively.

A metal-organic framework based on 5-iodo-isophthalic acid (5-iipaH2) and the ancillary nitrogen ligand 1,3-bi(4- pyridyl)propane (bpp), namely [Cd(5-iipa)(bpp)(H2O)]n (1), has been synthesized, and characterized by IR spectroscopy, elemental analysis, thermogravimetry, and X-ray crystallography. Complex 1shows a two-fold interpenetrating 3D diamond-like architecture that is stabilized by hydrogen bonding, μ...μ, I...μ, and C-H...p interactions.

The reaction of AgNO3, pyrazine (pyz) and 1,2,3-benzenetricarboxylic acid (H3btc) leads to a new 3D supramolecular architecture, namely {[Ag(H2btc)(pyz)]·(H2O)2}n (1), which has been characterized by IR spectroscopy, elemental analysis, thermogravimetry, photoluminescent and powder X-ray diffraction (PXRD). Compound 1 displays a 3D supramolecular network, which is built from cationic Ag–pyz chains and anionic [(H2btc)n·2H2O]− layers through the weak Ag⋯O interaction. Complex 1 exhibits photoluminesscence with an emission maximum at ca.391 nm upon excitation at ca. 241 nm.

A series of four novel cobaltic coordination polymers based on 5-iodo-isophthalic acid (5-iipa) and 1,1′-(1,4-butanediyl)bis(imidazole) (bbi), namely, [Co(5-iipa)(bbi)·3(H2O)]n (1), [Co2(5-iipa)2(b...

In this paper a novel strategy that aimed to coordinate the hydrolysis rates of different silanes was used to prepare PMOs. Attribute to the organic precursor released from the CH2Cl2 phase, the hydrolytic process of organosilane was obviously changed in the water-surfactant system. Consequently, the hydrolysis rates of different silanes do well match in a macroscopic level. These PMO materials were characterized by TEM and powder XRD. All the results indicated that large organic functionalized PMO materials with highly ordered hexagonal mesostructure and high loading of organic species were successfully prepared, while the 29Si MAS NMR experiment proved the organic species had been incorporated into the framework.

Cellulosome is a kind of multienzyme complex that displays high activity, selectivity and stability. Here, we report a novel, non-cellulolytic, cellulosome-like multienzyme complex that produced by the Cellulosimicrobium cellulans wild-type strain F16 isolated from soil microflora. This multienzyme complex, with excellent catalytic efficiency of kcat 13.2 s−1 to remove the C-7 xylosyl group from 7-xylosyl-10-deacetylpaclitaxel (10-DAXP), has an outstanding tolerance against organic solvents and an excellent general stability, with the long half-life of 214 hours. This cellulosome-like multienzyme complex has a novel structure distinct from the well-documented ones. The key catalytic subunit responsible for the β-xylosidase activity against 10-DAXP is identified to be a novel protein, indicating a new glycoside hydrolase (GH) family. The pioneering work described here offers a novel nanoscale biocatalyst for the production of biofuels and chemicals from renewable plant-based natural resources.

To speed up the pro duct design efficiency, product designers would like to utilize the previous design knowledge. This requires a systematic and structured way for design knowledge representation and reuse. A new method which is named knowledge component to make design knowledge reused conveniently is presented in this paper. Knowledge component is a virtual reuse model which has specific function. The internal structure and working principle of knowledge component are discussed; meanwhile the involved design knowledge was analyzed in detail. The design process of barrel chamber was taken as an example to illustrate the executing process of knowledge component. Testing result shows that this method is feasible in terms of increasing design efficiency and helps the designers reuse the existing knowledge rapidly.

Considering the importance of increasing driving safety, the study of safety is a popular and critical topic of research in the vehicle industry. Vehicle roll behavior with sudden steering input is a main source of untripped rollover. However, previous research has seldom considered road excitation and its coupled effect on vehicle lateral response when focusing on lateral and vertical dynamics. To address this issue, a novel method was used to evaluate effects of varying road level and steering wheel input on vehicle roll behavior. Then, a 9 degree of freedom (9-DOF) full-car roll nonlinear model including vertical and lateral dynamics was developed to study vehicle roll dynamics with or without of road excitation. Based on a 6-DOF half-car roll model and 9-DOF full-car nonlinear model, relationship between three-dimensional (3-D) road excitation and various steering wheel inputs on vehicle roll performance was studied. Finally, an E-Class (SUV) level car model in CARSIM® was used, as a benchmark, with and without road input conditions. Both half-car and full-car models were analyzed under steering wheel inputs of 5°, 10° and 15°. Simulation results showed that the half-car model considering road input was found to have a maximum accuracy of 65%. Whereas, the full-car model had a minimum accuracy of 85%, which was significantly higher compared to the half-car model under the same scenario.

Economic relations of modern enterprises are the most important factor for the modern enterprise management in Manufacturing Engineering, which is mainly carried out by contract and the effectiveness of contract. As foreign construction enterprises entering China market, with their advantages of powerful funds technology and management, China's construction enterprises will exert enormous pressure and impact. Meanwhile, our construction enterprises couldn’t be in order to enter the international market and international competition, without high level of contract management. For this reason, China's construction enterprises should be attention to contract management, and improve awareness of all employees of the contract. The contract management is into business management, it should be allowed to operate freely according to the law, to accelerate the development of construction enterprises in China.

A 10-mm-long cylindrical shell was written in neodymium doped phosphate glass by a femtosecond laser delivering pulses with a pulse repetition of 1 kHz, energies of 90 uJ and duration of 120 fs. The pulses were focused below the glass surface by an objective producing ablation filaments about 200 um in length. During processing, the sample was placed on a three-dimensional (3-D) translation stage, which moved along an enclosed pattern in the horizontal plane followed by a minor descent less than the filament length in the vertical direction. As this procedure continued, a cylinder, which demonstrated optical waveguiding, was fabricated with a rarified periphery and densified center region due to plasmonic expansion and outward shockwave upon laser ablation. The refractive-index contrast, propagation loss, near- and farfield mode distribution, and microscopic fluorescence micrograph of the waveguides were measured. 1-to-N splitters with adjustable splitting ratio were also fabricated using current approach indicating its 3-D processing flexibility. Compared with previous femtosecond laser fabrication methods, waveguides prepared in this approach exploit both depressed cladding and stress-induced refractive index increase in core region and show controllable mode conduction, strong field confinement, large numerical aperture, low propagation loss, acceptable thermal stability and intact core region.

The cucumber (Cucumis sativus) fruit is covered with bloom trichomes and warts (composed of spines and tubercules), which have an important impact on the commercial value of the crop. However, little is known about the regulatory mechanism underlying their formation. Here, we reported that the cucumber WD-repeat homolog CsTTG1, which is localized in the nucleus and cytomembrane, plays an important role in the formation of cucumber fruit bloom trichomes and warts. Functional characterization of CsTTG1 revealed that it is mainly expressed in the epidermis of cucumber ovary and that its overexpression in cucumber alters the density of fruit bloom trichomes and spines, thereby promoting the warty fruit trait. Conversely, silencing CsTTG1 expression inhibits the initiation of fruit spines. Molecular and genetic analyses showed that CsTTG1 acts in parallel to Mict/CsGL1, a key trichome formation factor, to regulate the initiation of fruit trichomes, including fruit bloom trichomes and spines, and that the further differentiation of fruit spines and formation of tubercules regulated by CsTTG1 is dependent on Mict Using yeast two-hybrid assay and bimolecular fluorescence complementation assay, we determined that CsTTG1 directly interacts with Mict. Collectively, our results indicate that CsTTG1 is an important component of the molecular network that regulates fruit bloom trichome and wart formation in cucumber.

We report on the formation and the optical properties of the planar and ridge optical waveguides in rutile TiO₂ crystal by He+ ion implantation combined with micro-fabrication technologies. Planar optical waveguides in TiO₂ are fabricated by high-energy (2.8 MeV) He+-ion implantation with a dose of 3 × 10¹⁶ ions/cm² and triple low energies (450, 500, 550) keV He+-ion implantation with all fluences of 2 × 10¹⁶ ions/cm² at room temperature. The guided modes were measured by a modal 2010 prism coupler at wavelength of 1539 nm. There are damage profiles in ion-implanted waveguides by Rutherford backscattering (RBS)/channeling measurements. The refractive-index profile of the 2.8 MeV He+-implanted waveguide was analyzed based on RCM (Reflected Calculation Method). Also ridge waveguides were fabricated by femtosecond laser ablation on 2.8 MeV ion implanted planar waveguide and Ar ion beam etching on the basis of triple keV ion implanted planar waveguide, separately. The loss of the ridge waveguide was estimated. The measured near-field intensity distributions of the planar and ridge modes are all shown.

We report on the fabrication of stress-induced optical channel waveguides and waveguide splitters with laser-depressed cladding by femtosecond laser. The laser beam was focused into neodymium doped phosphate glass by an objective producing a destructive filament. By moving the sample along an enclosed routine in the horizontal plane followed by a minor descent less than the filament length in the vertical direction, a cylinder with rarified periphery and densified center region was fabricated. Lining up the segments in partially overlapping sequence enabled waveguiding therein. The refractive-index contrast, near- and far-field mode distribution and confocal microscope fluorescence image of the waveguide were obtained. 1-to-2, 1-to-3 and 1-to-4 splitters were also machined with adjustable splitting ratio. Compared with traditional femtosecond laser writing methods, waveguides prepared by this approach showed controllable mode conduction, strong field confinement, large numerical aperture, low propagation loss and intact core region.

We report on the formation and the optical properties of the planar and ridge optical waveguides in rutile TiO2 crystal by He+ ion implantation combined with micro-fabrication technologies. Planar optical waveguides in TiO2 are fabricated by high-energy (2.8 MeV) He+-ion implantation with a dose of 3 × 1016 ions/cm2 and triple low energies (450, 500, 550) keV He+-ion implantation with all fluences of 2 × 1016 ions/cm2 at room temperature. The guided modes were measured by a modal 2010 prism coupler at wavelength of 1539 nm. There are damage profiles in ion-implanted waveguides by Rutherford backscattering (RBS)/channeling measurements. The refractive-index profile of the 2.8 MeV He+-implanted waveguide was analyzed based on RCM (Reflected Calculation Method). Also ridge waveguides were fabricated by femtosecond laser ablation on 2.8 MeV ion implanted planar waveguide and Ar ion beam etching on the basis of triple keV ion implanted planar waveguide, separately. The loss of the ridge waveguide was estimated. The measured near-field intensity distributions of the planar and ridge modes are all shown.