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Quasi-2D perovskites, composed of self-organized quantum well structures, are emerging as gain materials for laser applications. Here we investigate the influence of domain distribution on the laser emission of CsPbCl

Background: Bacterial mastitis in cows is a huge challenge to the dairy cattle breeding and production industry. This study examined the relationship between mastitis and bacterial diversity at different sampling sites in dairy farms. Methods: High-throughput sequencing of 16S rRNA V4 region was used to analyze the abundance and diversity of bacterial population sampled from seven different sites in a dairy farm, named healthy cow milk (N), cow milk from a mastitis cow (C), perimammary (T), milk collecting cup (B), turntable surface (P), feces (F) and bedding material (W). Result: In total, 2757356 reads were obtained from the sequencing results, which were annotated to 29 phyla, 67 classes, 166 orders, 295 families, 696 genera and 306 species. In all samples, Proteobacteria and Firmicutes were the dominant microflora, while Oscillospira-UCG-005 and Atopostipes were the dominant genera in different proportions, indicating certain differences in bacterial flora structure among different samples. Furthermore, alpha diversity analysis revealed high richness and diversity among different samples.

Professional women need to pay more attention to their health issues because of the pressure from careers and families. The digital art of health data generation reconstructs the health status of working women in a continuously changing “tree” image, aiming to help them pleasantly improve their health. The image combines electromyographic acquisition, physiological health data screening, data visualization, 3D real-time rendering technology, and human-computer interaction to investigate the relevance of continuous health monitoring and digital art generation. The image of the “tree” is generated by digital art, which presents the health condition more vividly. According to the experimental and statistical results, this kind of visual representation based on periodic health data can enhance their continuity, motivation, and action to focus on health and help them alleviate their anxiety about health problems.

Perovskite quantum dots are emerging as functional materials for modern optics and optoelectronics due to their superior optical properties and easy integration. In this work, we demonstrated novel...

Continuous-wave (CW) operated laser is a key component for photonic chips. It has been highly desired to develop low-threshold, high-efficiency, long-term operational, low-cost and easily integratable CW laser. As excellent optical gain materials, quantum dots (QDs) have been intensively investigated for on-chip CW lasers owing to their high photoluminescence quantum yields, tunable emission wavelengths and easy integration. Base on the difference of preparation processes, QDs can be classified into epitaxial QDs and solution-processed colloidal QDs (CQDs). In this mini-review, we summarize the research progresses of epitaxial III–V semiconductor QD and solution-processed CQD-based CW lasers. The challenges associated with the realization of CQD CW lasers are discussed in detail. In particular, the emerging perovskite-based CW lasers are highlighted. Finally, a short perspective of QD-based CW lasers is presented.

Room-temperature-operated continuous-wave lasers have been intensively pursed in the field of on-chip photonics. The realization of a continuous-wave laser strongly relies on the development of gain materials. To date, there is still a huge gap between the current gain materials and commercial requirements. In this work, we demonstrate continuous-wave lasers at room temperature using rationally designed in situ fabricated perovskite quantum dots in polyacrylonitrile films on a distributed feedback cavity. The achieved threshold values are 15, 24, and 58 W/cm2 for green, red, and blue lasers, respectively, which are one order lower than the reported values for the conventional CdSe quantum dot-based continuous-wave laser. Except for the high photoluminescence quantum yields, smooth surface, and high thermal conductivity of the resulting films, the key success of an ultralow laser threshold can be explained by the interaction of polyacrylonitrile and perovskite induced “charge spatial separation” effects. This progress opens up a door to achieve on-chip continuous-wave lasers for photonic applications.

As large storage tank has large diameter, the acoustic emission (AE) wave attenuation will increase. The number of location events may be lost. The activity of the defect cannot be understood. Reliability of safety assessment of tank bottom corrosion will be affected. In order to solve the problem, an acoustic source identification method is presented. Based on the AE source location theory of tank bottom, it is put forward that the sensors located on the tank bottom medium are employed together with the sensors arranged on tank outside wall near tank bottom to identify the acoustic source of tank bottom corrosion defects. Experiments of acoustic source location and identification for simulative tank bottom corrosion have been conducted. The results show that the method can help for recognizing acoustic source in arbitrary triangle and area location of tank bottom area; in addition, the sensor inside the tank is more sensitive to the identification of corrosion acoustic source than the external sensor. Therefore, the method can improve the reliability of results for the identification and location of tank bottom acoustic source.

A wideband butterfly antenna based on deep learning parameter optimization algorithm is proposed in this paper. Two neural networks are designed to model the mapping relationship of structure parameters to frequency response and frequency response to structure parameters respectively. The parameter optimization algorithm proposed consists of two stages: training NN1 and optimizing parameters using NN2. A wideband butterfly antenna is designed to verify the algorithm. The experiment shows that the structure parameter optimization algorithm proposed can quickly optimize the structure parameters of antenna with the best preformance and save a lot of manpower and time cost.

Purpose Measurement uncertainty calculation is an important and complicated problem in digitised components inspection. In such inspections, a coordinate measuring machine (CMM) and laser scanner are usually used to get the surface point clouds of the component in different postures. Then, the point clouds are registered to construct fully connected point clouds of the component’s surfaces. However, in most cases, the measurement uncertainty is difficult to estimate after the scanned point cloud has been registered. This paper aims to propose a simplified method for calculating the uncertainty of point cloud measurements based on spatial feature registration. Design/methodology/approach In the proposed method, algorithmic models are used to calculate the point cloud measurement uncertainty based on noncontact measurements of the planes, lines and points of the component and spatial feature registration. Findings The measurement uncertainty based on spatial feature registration is related to the mutual position of registration features and the number of sensor commutation in the scanning process, but not to the spatial distribution of the measured feature. The results of experiments conducted verify the efficacy of the proposed method. Originality/value The proposed method provides an efficient algorithm for calculating the measurement uncertainty of registration point clouds based on part features, and therefore has important theoretical and practical significance in digitised components inspection.

Selenocysteine (Sec), which is a biological selenol incorporated into selenoproteins specifically, plays vital roles in physiological processes and cancer treatment. However, there are limited fluorescent probes for selective detection of Sec and in only one case is a near-infrared (IR) fluorescent probe applied in biological imaging of Sec in living animals. In this work, we have synthesized a new fluorophore, boron-dibenzopyrromethene (B-Bodipy), with an absorption maximum at 650–660 nm, and constructed two deep red fluorescent probes, Sel-p1 and Sel-p2, which are two ethers composed of a 2,4-dinitrobenzenoxy and B-Bodipy moiety. Experiments in solution show that the two probes can react effectively with selenols to release the fluorophore via aromatic nucleophilic substitution (SNAr), with a low limit of detection (16 nM and 9 nM), high selectivity and excellent photostability. The potential application for the detection of Sec in cells has been demonstrated by cell imaging experiments of Sel-p2, including detection of exogenous Sec and selenite-induced Sec in living cells. Furthermore, Sel-p2 as a red fluorescent probe can achieve the detection of Sec in animals by mice imaging experiments.

Nitric oxide (NO) is an important signaling molecule involved in many physiological and pathological processes. To understand these NO-mediated processes, it is a key to develop rapid and specific detection methods for NO. In the past 2 decades, numerous excellent fluorescent probes for NO have been designed; however, it still remains limitations such as slow response, low selectivity, and short excitation wavelength (600 nm). In this Article, a two-photon fluorescent probe, NO-QA5, has been developed with 3-dimethylaminophenyl linking at the 6-position of 5-aminoquinoline as both the active site and prefluorophore for detection of NO. The nonfluorescent NO-QA5 can fast react with NO via a diazonium intermediate to generate two azoic regioisomers, one of which exhibits intramolecular charge transfer (ICT) emission, and two-photon absorption behavior (δΦ = 57 GM), giving a turn-on fluorescence rapid response. The sensing reaction is pH-insensitive in the range of 6-11 and highly selective and well sensitive (LOD = 15 nM), possible undergoing the same intermediate diazonium with the reaction under diazotization condition (NaNO

A new series of donor-acceptor-π-linker-acceptor (D–A–π–A) featured organic dyes containing Bodipy derivative as the auxiliary acceptor, furan unit as the π conjugated spacer, and 2-cyanoacrylic acid as the anchor group were synthesized and applied in dye-sensitized solar cells (DSSCs). The incorporated electron-withdrawing unit of Bodipy enhances light harvesting by decreasing the molecular energy gap and red-shifting absorption spectra. For comparison, three different arylamine chromophores namely 3-methoxy-9 H -carbazole ( CBZ-B ), triphenylamine ( TPA-B ) and phenoxazine ( POZ-B ) were separately appended onto the 6-position of Bodipy unit to study the effect of the electron donating groups on device performance. The UV–vis absorption spectra, electrochemical properties, density functional theory calculation, photovoltaic properties and electrochemical impedance measurements of DSSCs with these three dyes were systematically investigated. The Bodipy dyes have broad absorption spectra covering the range of 250–700 nm with the highest molar extinction coefficient up to >55 000 M −1 cm −1 . The molecular energy level tuning can be conveniently accomplished by alternating the donor moiety. The DSSCs based on TPA-B showed the best photovoltaic performance: a maximum monochromatic incident photon-to-current conversion efficiency (IPCE) of 70%, a short-circuit photocurrent density ( J sc ) of 13.95 mA cm −2 , an open-circuit photovoltage ( V oc ) of 557 mV, and a fill factor ( ff ) of 0.61, corresponding to an overall conversion efficiency of 4.76% under standard global AM 1.5G solar light conditions. Our research demonstrates that Bodipy based D–A–π–A molecular architecture is a highly promising class for the improvement of the performance of DSSCs in the future.

Development of multi-input fluorescent probes would facilitate the monitoring of multiple biomolecular events leading to a common disease pathology. Here, we reported a two-input fluorescent probe (QME-N3) based on quinoline scaffold with two distinct reactive sites, the α,β-unsaturated carbonyl at 2-site and 6-azido group, which were specific acceptors of RSH and H2S respectively. The turn-on fluorescent probe could react with the two molecules via the Michael addition at the double bond for RSH and the reduction of the azide by H2S without mutual interference, to generate the intensively fluorescent product, which could act as a two-input AND logic gate. Furthermore, QME-N3 has very low cytotoxicity and excellent stability, and the resulting sensing product has a high two-photon absorption cross section. Consequently, detection of intracellular thiols and H2S can be achieved by cell fluorescence imaging under both one- and two-photon excitations.

Titanium nitride (TiN) is a promising plasmonic material with hard and abrasion-resistant specialities. In this study, a gain regime, namely, plasmon-enhanced random laser emission, is demonstrated in the Pyrromethene-597 (PM597) assisted by titanium nitride (TiN) film. For this, photoluminescence and random lasing are measured at different pumping energies from PM597/Silicon and PM597/TiN/Silicon samples. Enhanced lasing efficiency is observed in the PM597/TiN/silicon sample where a plasmon resonance is formed, which increases the energy transfer between TiN and PM597. Furthermore, the multiple scattering mediated by the TiN film also plays an important role for the lasing efficiency. It is worth mentioning that the random laser emission has a strong dependence on pump position. The study of the random laser from PM597/TiN/Silicon sample with film structure is aimed to obtain a good alternative (TiN) to replace noble metals at a lowest cost.

A CAD-based approach to plan the laser scanning path of complex surfaces is presented. Firstly, in the laser scanning process the issues of the positional relationship between scanning direction and normal vectors of sampling points of the measured surface, sensor work area check and surface occlusion judgment are researched and a method for generating a single arbitrary surface scanning path is developed. Secondly, through the analysis of surface segmentation, scanning directions and displacements synthesis during the multi-surface scanning process, a scanning path planning method based on any complex multi-curved surface is established. Finally, through a simulation example, the feasibility of the method is verified.

A Michael addition is usually taken as a base-catalysed reaction. However, our synthesized 2-(quinolin-2-ylmethylene) malonic acid (QMA) as a Michael-type thiol fluorescent probe is acid-active in its sensing reaction. In this work, based on theoretic calculation and experimental study on 7-hydroxy-2-(quinolin-2-ylmethylene) malonic acid, we demonstrated that QMA as a Michael acceptor is acid-activatable, i.e., it works only in solutions at pH

Majority of taxi recommender systems mainly focused on satisfaction of passengers without considering fairness in assignment of taxi drivers. In this paper we propose a balanced assignment mechanism for online taxi recommendation (BAMOTR). BAMOTR provides a mechanism for fair assignment of drivers at some locations with specific routes to pick up passengers and ensures a short waiting time for passengers. Fair assignment is intended to minimize the differences in income among the taxi drivers. Analysis shows out that fair assignment of drivers and shortening the time the passenger wait before pick up is a trade-off problem. In this paper, we set a regulatory factor that can adjust the trade-off between fair assignment of drivers and shortening of waiting time of passengers. We also propose an efficient range refinement algorithm to solve online taxi recommendation problem in BAMOTR. It is theoretically and experimentally proved that range refinement algorithm ensures the same recommendation result as brute-force algorithm, however it greatly reduces the time overhead. We validate the performances of BAMOTR with extensive evaluations. Experimental results show that BAMOTR achieve better recommendation fairness than compared approaches and guarantee a short waiting time for passengers to be picked up.

Hydrogen sulfide (H2S) is an important signaling molecule with diverse biological roles. Various fluorescent probes for H2S with biological application have been developed. However, two-photon ratiometric imaging of mitochondrial H2S is scarce. In this paper, we report two ratiometric two-photon probes, AcHS-1 and AcHS-2, which employ 4-amino-1,8-naphthalimide as the fluorophore and 4-azidobenzyl carbamate as the H2S response site. These probes exhibit high selectivity toward H2S over biothiols and other reactive species, low detection limits of 50-85 nM, low cytotoxicity, and high stability under physiological conditions. Furthermore, through cell imaging with one-photon and two-photon microscopy, MCF-7 cells incubated with two probes show a marked change in emission color from blue to green in response to H2S. Cell images costraining with a mitochondrial dye reveal that AcHS-2 is a mitochondria-specific two-photon probe for H2S. These results show that AcHS-2 may find useful applications in biological research such as tracking mitochondrial H2S in living biological specimens.

In a linear multi-secret sharing scheme with non-threshold structures, several secret values are shared among n participants, and every secret value has a specified access structure. The efficiency of a multi-secret sharing scheme is measured by means of the complexity σ and the randomness τ. Informally, the complexity σ is the ratio between the maximum of information received by each participant and the minimum of information corresponding to every key. The randomness τ is the ratio between the amount of information distributed to the set of users U = {1, ⋯, n} and the minimum of information corresponding to every key. In this paper, we discuss σ and τ of any linear multi-secret sharing schemes realized by linear codes with non-threshold structures, and provide two algorithms to make σ and τ to be the minimum, respectively. That is, they are optimal.

Generalization of large margin classification methods from the binary classification setting to the more general multicategory setting is often found to be non-trivial. In this paper, we study large margin classification methods that can be seamlessly applied to both settings, with the binary setting simply as a special case. In particular, we explore the Fisher consistency properties of multicategory majorization losses and present a construction framework of majorization losses of the 0-1 loss. Under this framework, we conduct an in-depth analysis about three widely used multicategory hinge losses. Corresponding to the three hinge losses, we propose three multicategory majorization losses based on a coherence function. The limits of the three coherence losses as the temperature approaches zero are the corresponding hinge losses, and the limits of the minimizers of their expected errors are the minimizers of the expected errors of the corresponding hinge losses. Finally, we develop multicategory large margin classification methods by using a so-called multiclass C-loss.

At present, the detection of weak corrosion current is not perfect and automated, to solve the problem, this paper put forward and designed a kind of weak and wide-range corrosion current real-time detection circuit with functions of automatic switching range . By choosing low bias current and high precision operational amplifier, using I - V conversion technology transform the weak current into voltage, then do voltage signal acquisition, using the SD card module and electronic analog switch combined with single chip microcomputer to realize real-time and auto-switching detection of the corrosion current. This circuit has good real-time performance and accuracy, and can achieve the corrosion current value that was outputted by gas corrosion sensor well.

In industrial production, the machine vision save a lot of manpower and material resources. And it has become an indispensable part of quality control solutions in automobile and parts manufacturing. In order to detect the integrity of automatic assembly for lamp parts, we first use the shape feature to determine whether the part shape is right through egde detection and template matching algorithms. And if the shape is right, we can further detect the color feature which are different in different sales regions using the color moments. As a result, the missing and mistake packing can be detected.

3D reconstruction as the basis of many applications,such as 3D printing, has become more and more importantfor many enterprises and researchersThe very important step in 3D reconstruction is the joining together of point cloud.This paper introduces the structures of a system to obtain three-dimensional point cloud data and a kind ofmethodsusing of the system to get point cloud data through the rotation and translation of the coordinate system, joining together the point cloud data.Experiment shows that this method has achieved good effect.

A novel carbon-based solid acid was successfully prepared by sulfonation of cocarbonized starch and polyvinyl chloride (PVC). The characterization results show that this catalyst possesses all characteristics of traditional carbon-based solid acids (CSAs). The differences are that chlorine from PVC is covalently bonded to edges of aromatic carbon sheets as new active groups, and ether (C–O–C) and aliphatic (–CH2–) bridges are formed during the cocarbonization process which are derived from oxygen in starch and alkyl in PVC, respectively. Chlorine groups can adsorb cellulose hydroxyl groups strongly and bridge bonds make the carbon framework fully stretch, which reduces hindrance between SO3H groups and glycosidic bonds to promote the catalytic performance in cellulose hydrolysis experiments. Furthermore, the durability results indicate that this catalyst has good stability.

Random lasers (RLs) offer new functionalities inaccessible with conventional lasers, such as an alterable shape and an easy integration with flexible optoelectronic devices. Here, we demonstrate a stretchable and threshold tunable RL by modulating the order degree of the nematic liquid crystal (NLC) that is caused by the alignment of polymer chain under tensile force. The lasing thresholds show a “U” shape curve variation trend, which is attributed to the competition between the partial orientation of the NLC molecules and the reduction of the dye and NLC densities. The results are further confirmed by the power Fourier transform (PFT) spectrum analysis. This work evokes deeper understanding of the effect of order degree on RLs and extends the applications of polymer polyvinylidene fluoride (PVDF) on tunable RLs.

PMP-AODV routing protocol which introduces priority setting, multi-point relay and path stability is proposed. The algorithm message format is discussed, the MPR selection algorithm is elaborated, the measurement of stability of path is designed, and the working flow of PMP-AODV is analyzed. The simulation result shows that the PMP-AODV protocol is less packet loss rate and lower end-to-end delay than original AODV protocol under the large wireless Mesh network.

A novel process of manufacturing high performance AZ31 alloy strip was put forward by combining semisolid rolling, deep rolling and heat treatment, and the effects of dynamic recrystallisation during deep rolling of semisolid slab and heat treatment on microstructure and properties of AZ31 alloy were investigated. When the casting temperature was set from 650 to 690°C and the vibration frequency was controlled at 80 Hz, AZ31 alloy strip with the cross-section size of 4×160 mm and fine near round and rosette grains was manufactured by semisolid rolling. Dynamic recrystallisation happened during deep rolling process. Dynamic recrystallisation grain size decreases with the increase in deep rolling temperature in a certain scope. With the increase in deep rolling deformation amount, the microstructure evolved gradually from coarse primary grains and twins to fine dynamic recrystallisation grains and twist primary grains as well as small regular equiaxed grains. AZ31 alloy strip with very fine equiaxed...

Light shape detection of headlamps is an important project of yearly check. In the aspect of lowbeam detection, it is necessary to not only accurately calculate the boundary between brightness and shade, but also optical axis intersection point. By the principle that the second derivative indicates the concavity and convexity of functions, a polynomial fitting is used to calculate the columns grayscale profile of a lowbeam figure, and then get the cut-off point through second derivative of a polynomial. The boundary between brightness and shade is consisted of these cut-off points. The optical axis intersection point is obtained by second order difference of the boundary. While fully extracting graphic features, the method precisely locates positions of the boundary and the intersection.

A novel method of measuring gap and surface differential was proposed to detect headlights contour in this paper. The method is based on the line structured laser sensor and robot system, and spline curve fitting was used to obtain the contour of the headlights and mold. After the fitting, the contour was resampled to get the shortest distance vector between the headlight contour curves and the mold contour curves, and through the decomposition of the vectors, the perpendicular and parallel components were obtained, and then the gap and surface differential measurement was completed.

This paper puts forward a method to control the industrial robots based on the NI Corporations LabVIEW virtual instrument technology. By designing the communication protocol between the LabVIEW software program on PC and industrial robots, the LabVIEW program can take the control of industrial robots by using RS232 serial ports, including the operation instructions' transmission, the feedback of the robots' running, and the data exchange between the two. The result shows that can effectively realize the motion control of industrial robots based on LabVIEW.

Support vector machine (SVM) is the state-of-the-art classification method, and the doubly regularized SVM (DrSVM) is an important extension based on the elastic net penalty. DrSVM has been successfully applied in handling variable selection while retaining (or discarding) correlated variables. However, it is challenging to solve this model. In this paper we develop an iterative @?"2-SVM approach to implement DrSVM over high-dimensional datasets. Our approach can significantly reduce the computation complexity. Moreover, the corresponding algorithms have global convergence property. Empirical results over the simulated and real-world gene datasets are encouraging.

Due to the impact of the lens optical system and the different manufacturing processes, there could be causing the vignetting when using a CCD camera to take pictures. This paper analyzes the causes of the lens vignetting and put forward a method for reducing this error to improve the accuracy of the intensity of illumination detection. Firstly, according to the analysis of the existing research on the camera lens, concluded that there are two factors that cause vignetting. Secondly, based on the conclusion, do large amounts of test in each case. Analyze for the influence of illumination test in each case. Finally, the article put forward a set of vignetting correction method to correct the image be collected in a fixed aperture. The result shows that the method can effectively reduce vignetting measuring error and has a good stability.

Camshift tracking algorithm is based on probability distribution of color , it is susceptible to be interfered by the same color in the background, which will lead to the failure of the target tracking. To overcome this problem it presented an improved Camshift tracking algorithm. It combined background subtraction method with three frame difference method to detect target, got rectangular characteristic parameters of the motion target area as the Camshift initialization parameters, replaced the general Camshift algorithm which is based on color feature. Experimental results show that Camshift algorithm combining the background subtraction method with three frame difference method can meet the requirements of the real-time and stability to a certain extent.

For wafer defects detection system in a certain resolution, CCD camera cannot get the whole wafer image at one-time, which has an influence on the subsequent defect feature extraction. This paper puts forward an image registration method based on geometry features. Firstly, the information of the image edge can be extracted by using an improved edge detection operator, then using Hough transform to extract the horizontal and vertical lines of the information of the image edge. Secondly, using the correlation of linear characteristic to define the registration standards of the image. A new method, simplex-simulated annealing algorithm, is presented to optimize the registration coefficient of the image. Finally the method is tested and evaluated by the matching effect, the results show that it can effectively achieve the automatic wafer image registration and has a good stability.

This paper put forward a 3D reconstruction method of the headlight contours based on laser scanning technology and robotics. Firstly, according to the present three-dimensional measurement techniques, the article put forward a set of headlight contour detection method based on the analytic geometry model and the line laser source scanning principle. It establishes a 3D scanning model and coordinate transformation model for 3D reconstruction of the headlight contour. Secondly, according to the demanding accuracy it structures the 3D reconstruction system. Finally it realizes the 3D reconstruction of the headlight contour based on the method, and the result is tested and evaluated matching effect, the result shows that can effectively realize the 3D reconstruction of headlight contour and the method has a good stability.

A novel continuous semisolid rolling process for producing AZ31 alloy strip was developed. The process parameters were optimized, and microstructure and properties of AZ31 alloy prepared by the process were studied. The results reveal that primary grains of the strip become coarse, and the grain structure transforms from round shape to dendrite with the increment of casting temperature gradually. Eutectic phase fraction and primary grain size increase with the increment of roll speed. The primary grain size decreases firstly and then increases with the increment of the vibration frequency correspondingly. When the casting temperature is from 650 °C to 690 °C, the roll speed is 0.069 m·s−1, and the vibration frequency is about 80 Hz, AZ31 alloy strip with a cross section size of 4 mm×160 mm was prepared by the proposed process. The ultimate tensile strength and elongation are improved 1% and 57%, respectively.

A novel semisolid rheo-rolling process of AZ31 alloy was achieved by combining the shape rolling mill with the vibrating sloping plate device. The process is expected to be developed as a high-speed, semisolid roll-casting technique. During the process, due to the strong cooling rate by the sloping plate and stirrings caused by vibration and metal flow, three mechanisms—heterogenous nucleation, eruptive nucleation, and nucleus multiplication—exist, which lead to fine spherical or rosette grains formation. Two grain-growing styles, direct globular growth, dendrite growth, and fracture happen on the sloping plate surface, which also devotes to the fine non dendrite formation. During the rolling process, the solid grain of the slurry is elongated a little, and its original shape is basically maintained. If the casting temperature is too high, the liquid segregation occurs. At the casting temperature range of 650–690°C, AZ31 alloy strip with a cross section size of 4 × 160 mm was prepared by the proposed proc...

As the rapid progress and development of DSP technology, a new way to solve the video signal processing was accepted. At present, binocular measurement instrument are mostly based on image capture card and PC on the market, expensive and bulky. For this problem, binocular vision measurement system based on DSP has been used. The design of elementary program structure about video processing which based on DSP/BIOS was finished and verified for its real-time. The results of the experiment show that the driver can be well used in the system.

A novel rheo-rolling process for producing A356 alloy sheet was developed. The influence of parameters on the microstructure of A356 alloy sheets was investigated. The eutectic fraction and primary α globule size increase with the increment in the roll speed. The globule size and eutectic fraction of A356 alloy sheet increase with the increment in the casting temperature. The primary α globule size decreases and the solid fraction increases with the increment in vibration frequency from 30 Hz to 80 Hz. With a roll speed of 0.069 m.s -1 , a casting temperature of 660 °C, and a vibration frequency of 80 Hz, A356 alloy sheet with a cross-section size of 4 × 160 mm was prepared. The microstructure is mainly composed of fine spherical or rosette α globules, and the average α globule size is 20.5 μ m. The ultimate tensile strength of the A356 alloy sheet was 260 MPa, and the elongation to failure was 7.9%, which were 2.5 and 3.7 times greater than those of the as-cast material.

Extending extrusion process of semisolid AA2017 alloy was achieved. Metal flow during the process was analyzed by the finite element simulation. It was shown that alloy flow velocity decreases gradually from the center part to the sides of the mould, sometimes a transitional turbulence region appears in the middle. A smaller declining angle θ and without step d is suggested in the design mould. Alloy flow velocity at the center of the forming region decreases linearly with increases of the extending ratio s1/s0.

Epidemiological and clinical data suggest that estrogen retards the progression of atherosclerosis. This study aims to elucidate whether the phenotypic regulation of human vascular smooth muscle cells (VSMC) by estrogen may involve effects on the hyaluronan matrix. VSMC were synchronized by serum withdrawal and subsequently stimulated with 0.001, 0.01, 0.1 and 1 μM estradiol (E(2)) in the presence or absence of platelet-derived growth factor BB (PDGF-BB) for 24 h. E(2) reduced mRNA-expression of hyaluronic acid synthase (HAS) 1 in the presence and absence of PDGF-BB. In contrast, HAS2- and HAS3-mRNA-expression were not affected. This E(2)-mediated effect on HAS1 mRNA-expression was accompanied by reduced hyaluronan secretion and a shift of HA toward lower molecular weight as evidenced by molecular sieve chromatography. The downregulation of HAS1 was abrogated by the estrogen receptor (ER) α and β antagonist ICI182780 and could be mimicked by the ERα-agonist propyl-pyrazole triol (PPT). On the contrary, the ERβ-agonist diarylpropionitrile (DPN) had no effect on HAS1 mRNA-expression. To investigate whether the downregulation of HAS1 was causally involved in the phenotypic regulation of human VSMC by E(2), lentiviral overexpression of HAS1 was conducted. Overexpression of HAS1 abrogated the inhibition of sustained ERK1/2 phosphorylation and in turn inhibition of DNA-synthesis by E(2). For the first time this study provides strong evidence that HAS1-driven HA-synthesis is a target of E(2) in human VSMC and that E(2) mediates part of its anti-proliferative effects through an ERα-dependent inhibition of HA-synthesis.

Myocardial infarction (MI) is followed by extracellular matrix (ECM) remodeling, which is on the one hand required for the healing response and the formation of stable scar tissue. However, on the other hand, ECM remodeling can lead to fibrosis and decreased ventricular compliance. The small leucine-rich proteoglycan (SLRP), biglycan (bgn), has been shown to be critically involved in these processes. During post-infarct remodeling cardiac fibroblasts differentiate into myofibroblasts which are the main cell type mediating ECM remodeling. The aim of the present study was to characterize the role of bgn in modulating the phenotype of cardiac fibroblasts. Cardiac fibroblasts were isolated from hearts of wild-type (WT) versus bgn(-/0) mice. Phenotypic characterization of the bgn(-/0) fibroblasts revealed increased proliferation. Importantly, this phenotype of bgn(-/0) fibroblasts was abolished to the WT level by reconstitution of biglycan in the ECM. TGF-β receptor II expression and phosphorylation of SMAD2 were increased. Furthermore, indicative of a myofibroblast phenotype bgn(-/0) fibroblasts were characterized by increased α-smooth muscle actin (α-SMA) incorporated into stress fibers, increased formation of focal adhesions, and increased contraction of collagen gels. Administration of neutralizing antibodies to TGF-β reversed the pro-proliferative, myofibroblastic phenotype. In vivo post-MI α-SMA, TGF-β receptor II expression, and SMAD2 phosphorylation were markedly increased in bgn(-/0) mice. Collectively, the data suggest that bgn deficiency promotes myofibroblast differentiation and proliferation in vitro and in vivo likely due to increased responses to TGF-β and SMAD2 signaling.

500nm AlGaN thick layer with AlGaN/GaN MQW interlayer was grown on sapphire substrate for UV detector and resonant tunneling diodes by MOCVD equipment. We were strongly interesting in the stress information of QW. There are a big mismatch of lattice between AlN and GaN.The growth of thick and high quality AlGaN is difficult task. AlGaN/GaN MQW layers were designed to relax the big mismatch stress. Many researcher focused on the stress relax mechanism for the growth of AlGaN alloy. The stress in QW can change the band gap structure and carrier contents of polarize induced charge. Raman spectra were a useful tool to observe the stress of semiconductor materials without damaging the sample. Using 514nm green laser, we only obtained the phonon modes of GaN. So applying 325nm Ar ion laser, we can observed the phonon modes spectra of both AlGaN and GaN layers. According to resonance conditions, the phonon modes of 789.74 cm-1 was origin from AlGaN alloy layer. The phonon modes of 740.89 cm-1 and 575.06 cm-1 were origin from GaN layer. Compared to other results, GaN layer was compress strain. We determined that AlGaN/GaN MQW interlayer relaxed strain stress from lattice mismatch, and phonon modes were clearly observed.

In this paper, the main problem is how to eliminate vibration came from the compressor base in petrochemical industry. The absolute transmissibility was calculated by building the compressor isolation system model. The spectrum information of compressor vibration was got through the vibration test, and the results can be acted as the condition for the isolator’s design. Isolators were designed with damping part connecting metal rubber with helical spring. Nonlinear simulation calculation was completed by finite element software. The results show that the maximum stress of isolator is about 494MPa and its maximum distortion is approximately 6mm. It verifies that the new-style isolator can satisfy vibration elimination of compressor. It is with wide-range rigidity and better capability of energy dissipation than that of general rubber isolator. It has a useful application and perspective on vibration elimination for the mechanical equipment in petrochemical industry.