以机器视觉定位提升自动贴膜机控制效能

机器视觉应用可以大大提高自动薄膜层压机的精度,并影响生产贴片机的性能利用率。传统的自动薄膜层压机使用ALT1.0进行物体识别。本文介绍的新方法是引入视觉识别软件和硬件的组合。隔膜被相应的机器提取后,EYESOFTWARE全局图像用于连接PLC。在使用语音模板进行数据值计算的过程中,整个控制过程将时间缩短到0.02秒/件,操作员可以将时间缩短3分钟,与去年同期相比。它对东莞制造业的转型升级具有借鉴意义,可用于电路板生产行业,带来核心技术。

真空膜蒸馏分离乙醇溶液试验研究

采用真空膜蒸馏装置处理乙醇溶液,探究采用真空膜蒸馏浓缩高浓度乙醇溶液时的膜蒸馏效能及可行性,考察进料温度、进料乙醇浓度等因素对膜蒸馏效能的影响。结果表明,温度能显著提高膜通量,当温度从50℃上升至75℃时,膜通量从3.90 kg/(m^(2)·h)增加至19.90 kg/(m^(2)·h),乙醇通量从1.84 kg/(m^(2)·h)增加到9.17 kg/(m^(2)·h);随着进料乙醇浓度的增加,膜通量与乙醇通量均升高。在浓缩时间为2.0~2.5 h时,高浓度乙醇溶液的膜蒸馏浓缩分离过程运行稳定,在浓缩时间超过2.5 h后,出水通量有增加的趋势,出水乙醇质量分数和分离比有下降的趋势,且膜面上出现浸润点,经试验分析可知膜发生浸润现象是由于管道和膜组件的材质在高温、高浓度下的乙醇溶液中不稳定所致,后续可应用其他材质的膜组件以及耐高温的新型膜材料进行处理。

大豆肽超滤分离纯化过程的研究

用板框型超滤器以全回流的方式对大豆肽粗品进行处理 ,通过测定不同浓度的大豆肽溶液在不同循环时间内滤出液的膜通量变化及截留液中固形物的含量 ,对超滤膜效能及其选择性进行了评价和分析。试验结果表明 ,超滤技术不仅能直接从发酵产物中分离出纯度较高的大豆肽 。

Growth and corrosion behaviors of thin anodic alumina membrane on AA5083 Al-Mg alloy in incalescent medium

A self-ordered porous film was fabricated on aluminum alloy in a ternary boric-sulfuric-oxalic acid electrolyte system. By means of voltage–time response, the oxidation process as well as the growth efficiency was studied. Field emission scanning electron microscopy（FE-SEM） was adopted to reveal the morphological and microstructural features of as-fabricated oxide layers. The corrosion protection properties of the films were investigated by electrochemical impedance spectroscopy and potentiodynamic polarization measurements. The results showed that increasing the concentration of the double ionic layer located at the oxide interface could accelerate the film growth rate. The anodic oxidative layer with thickness of 8-9 μm and pore diameter of 10-14 nm maintains the pattern and topography of workpieces, compared with the overall closed film with hierarchical structure. Both samples exhibited much lower corrosion current density after boil water sealing. Meanwhile, a superior stability could be achieved through raising the ambient temperature.

Effects of solubility parameter differences among PEG,PVP and CA on the preparation of ultrafiltration membranes:Impacts of solvents and additives on morphology,permeability and fouling performances

The effects of two different hydrophilic additives and two solvents on the membrane morphological structure,permeability property and anti-fouling performances of cellulose acetate(CA) ultrafiltration membranes were investigated. During the phase-inversion process, cellulose acetate was selected as a membrane forming polymer; polyethylene glycol(PEG) and polyvinyl pyrrolidone(PVP) were used as additives; acetone(Ac): N,N-Dimethylacetamide(DMAc) and N, N-Dimethylformamide(DMF) were used as solvents; and deionized(DI)water was used in the coagulation bath. All the prepared membranes were characterized in terms of hydraulic permeability(Pm), membrane resistance, average pore radius, and hydrophilicity. The top surface and crosssectional view of the prepared membranes were also observed by using field emission scanning electron microscopy. Membrane fouling and rejection experimentations were done using a stirred batch-cell filtration set-up.The experimental studies of fouling/rinsing cycles, rejection, and permeate fluxes were used to investigate the effect of PEG and PVP additives and effect of the two solvents on the fabricated membranes using bovine serum albumin(BSA) as a model protein.

鳖甲活性多肽的提取及膜分离纯化工艺优选

目的：优选鳖甲活性多肽的提取工艺及膜分离工艺。方法：以多肽提取量和浸膏得率为指标，通过正交试验考察料液比、提取时间、提取次数对鳖甲多肽提取工艺的影响；以膜渗透通量或膜效能为指标，运用单因素试验优选鳖甲活性多肽的膜分离工艺。结果：最佳提取工艺为醋鳖甲粉碎过24目筛，加6倍量水提取3次，每次3h；多肽提取量达2．442g，浸膏得率11．71％。膜分离纯化条件为鳖甲多肽质量分数6％，截留相对分子质量20，kD的超滤膜操作压力分别为0．18—0．21，0．8MPa；蛋白质截留率83．67％，相对分子质量〈8000的鳖甲多肽纯度达57．62％。结论：膜分离技术可用于鳖甲活性多肽的制备。

Patterning of Poly（3,4-Ethylenedioxythiophene）： Poly（Styrenesulfonate） Films via the Rubbing Method in Organic Photovoltaic Cells

OPV （Organic photovoltaic） cells represent a compelling candidate for renewable energy by solar energy conversion. In recent years, versatile light-trapping measures via structures have been intensively explored to optimize photovoltaic performance. In this work, a unique rubbing technique is demonstrated to create nanoscale grooves on the PEDOT：PSS [poly（3,4-ethylenedioxythiophene）： poly（styrenesulfonate）] surface and the grating-like features are 500 nm wide and 10 nm deep. The PEDOT：PSS film with grooved surface is used as buffer layers for OPV cell devices based on a P3HT：PCBM bulk heterojunction. The patterned surface has a profound effect on carrier mobility, light trapping, and hole collection efficiency, leading to an increase in the short circuit density, filling factor, and power conversion efficiency. These results indicate the feasibility of the rubbing method can be applicable to high-efficiency OPV cells.

Effects of coagulation bath temperature on structure and performance of poly(vinyl butyral) hollow fiber membranes via thermally induced phase separation

Poly （vinyl butyral） （PVB） hollow fiber membranes were fabricated via thermally induced phase separation （TIPS）. The effects of coagulation bath temperature （CBT） on the structure and performance of membranes were investigated in detail. The morphologies of the membranes were studied by scanning electron microscopy （SEM）, the performances of water permeability, rejection, breaking strength and elongation were measured, respectively. The results indicate that all the membranes have the asymmetric morphology and the thickness of the skin layer decreases and the pore size of the outer layer increases with the increase of CBT. The permeability of membranes prepared at air gap 1.0 cm and take-up speed 0.253 m/s increases from 1.047×10-7 to 5.909×10-7 m3/（m2·s-kPa） with the CBT increasing from 20 ℃ to 40℃, and sharply increases to 35.226×10 7 m3/（m2.s.kPa）once the CBT arrives at 50 ℃. While the carbonic ink rejections have no significant decrease, totally exceed 98%, but that of acid-maleic acid copolymer greatly decreases with the increase of CBT. Both the breaking strength and elongation decrease with the increase of CBT.

Influence of Water Vapor on Silica Membrane： Adsorption Properties and Percolation Effect

The influence of water vapor on silica membrane with pore size of ,-4A has been investigated in terms of adsorption properties and percolation effect at 50 and 90 ℃. Two methods are employed： spectroscopic ellipsometry for water vapor adsorption and gas permeation of binary mixture of helium and H2O The adsorption behaviors on the silica membrane comply with the first-order Langmuir isotherm. The investigation demonstrates that helium flux through the silica membrane decreases dramatically in presence of H20 molecules. The transport of gas molecules through such small pores is believed not to be continuous any more, whereas it is reasonably assumed that the gas molecules hop from one occupied site to another unoccupied one under the potential gradient. When the coverage of H20 molecules on the silica surface increases, the dramatic decrease of helium flux could be related to percolation effect, where the adsorbed H20 molecules on the silica surface block the hopping of helium molecules.

Effect of Substrate Temperature on Optical Characteristics of Silver Island Films for Harvesting Solar Energy

Due to their particular optical characteristics,metallic island films have the potential to significantly increase the energy conversion efficiency of solar cell.We experimentally and theoretically investigated the effect of substrate temperature on the morphologies and optical properties of the silver island films.At low temperature,below 300 ℃,as the substrate temperature increases.Compared to the films prepared at room temperature,the sizes of nanoparticles decrease and the Absorption peaks shift to shorter wavelength accompanied by an increase density resulting in a 150% Absorption efficiency.As the substrate temperature goes up to 300 ℃,nanoparticles with larger in-plan(X-Y)dimensions are formed,the number density decreases and the Absorption peaks redshift but the Absorption efficiency is still 10% higher.Numerical simulation reveals that these behaviors are a consequence of morphologies transformation.

MBR净化受污染地表水的自然启动及稳定运行除污染特性

为了考察膜生物反应器(MBR)净化受污染地表水自然启动过程中功能菌群的成熟规律及碱度对MBR去除水中氨氮的影响,通过构建小试规模的MBR,考察了MBR处理受污染地表水的自然启动和稳定运行除污染特性。结果表明,MBR在自然启动过程中不会出现异养菌成熟的标志,系统对进水DOC、UV254和CODMn的平均去除率分别仅为(14.5±5.1)%、(12.6±5.6)%和(31.2±7.4)%,应考虑将其他工艺与MBR联用以提高系统的有机物去除能力。启动23天后,MBR中的亚硝化细菌成熟,NH3-N去除率达到80%以上;启动31 d后,MBR中的硝化细菌成熟,出水NO2--N稳定在0.05mg/L以下。碱度对MBR去除NH3-N效能影响较大,向进水中投加30 mg/L的NaHCO3能使MBR对NH3-N的去除率由(86.1±3.7)%提高至(98.0±1.6)%。在连续曝气、10 L/(m2.h)通量、每10 min反洗15 s运行模式下,MBR的膜污染较为严重,平均TMP增长速率为0.45 kPa/d,需进一步优化相关参数以实现MBR的长期稳定运行。

Efficient perovskite solar cells based on novel three-dimensional TiO2 network architectures

Mesoscopic lead halide perovskite solar cells typically use TiO2 nanoparticle films as the scaffolds for electron-transport pathway and perovskite deposition. Here, we demonstrate that swelling-induced mesoporous block copolymers can be templates for producing three- dimensional TiO2 networks by combining the atomic layer deposition technique. Thickness adjustable TiO2 network is an excellent alternative scaffold material for efficient per- ovskite solar cells. Our best performing cells using such a 270 nm thick template have achieved a high efficiency of 12.5 % with pristine poly-3-hexylthiophene as a hole transport material. The high performance is attributed to the direct transport pathway and high absorption of scaf- folds, small leakage current and largely reduced recombi- nation rate at interfaces. The results show that TiO2 network architecture is a promising scaffold for meso- scopic perovskite solar cells.

Greater omentum in reconstruction of refractory wounds

Objective: To evaluate the clinical efficacy of greater omentum in reconstruction of refractory wounds. Methods: From August 1988 to May 2001, 20 patients with refractory wound underwent pedicle or microvascular free transfer of the greater omentum. Indications of surgery were electrical injury of the wrist and hand in 9 patients, electrical injury of the scalp and cranial bones in 3, avulsion injury of the scalp in 2, radiation-related ulcer of the chest wall in 2, ulcer and osteomyelitis following resection of the sternum sarcoma in 1, electrical injury of the abdomen in 1, bone and soft tissue defects following compound fracture of the leg in 1, and extensive scar and ulcer of the leg and footdrop following trauma in 1. Severe infection and extensive tissue necrosis were present prior to surgical operation in 12 patients. Eleven patients were treated with pedicled omental flaps, and 9 patients with free omental flaps. The size of the omental flaps ranged from 20 cm×12 cm to 38 cm×23 cm. Results: All the omental flaps survived. Healing at the first intention of the wounds was achieved in 17 cases. The on-top skin grafts resulted in partial necrosis of lipid liquefaction developed in the omentum and healed with dressing change in 2 cases. A sinus tract of osteomyelitis occurred in one case and healed after delayed excision of the necrosed bone. Follow-up study of all cases from 3 to 24 months showed no recurrent wounds and post-operative abdominal complication. Recovery with acceptable appearance and restoration of function was satisfactory. Conclusions: Greater omentum provides a well-vascularized tissue with lymphatic ducts for wound coverage. It has strong resistance against infection. It is very malleable and can be molded easily. Therefore it is an ideal tissue in filling cavities and repairing defects, especially in covering large and irregular defects that can not be treated with skin or muscle flaps.

Film Cooling Performance of a Row of Dual-fanned Holes at Various Injection Angles

Film cooling performance about a row of dual-fanned holes with injection angles of 30°, 60 ° and 90° were experimentally investigated at blowing ratios of 1.0 and 2.0. Dual-fanned hole is a novel shaped hole which has both inlet expansion and outlet expansion. A transient thermochromic liquid crystal technique was used to reveal the local values of film cooling effectiveness and heat transfer coefficient. The results show that injection angles have strong influence on the two dimensional distributions of film cooling effectiveness and heat transfer coefficient. For the small injection angle of 30 degree and small blowing ratio of 1.0, there is only a narrow spanwise region covered with film. The increase of injection angle and blowing ratio both leads to the enhanced spanwise film diffusion, but reduced local cooling ability far away from the hole. Injection angles have comprehensive influence on the averaged film cooling effectiveness for various x/d locations. As injection angles are 30 and 60 degree, two bands of high heat transfer coefficients are found in mixing region of the gas and coolant. As injection angle increases to 90 degree, the mixing leads to the enhanced heat transfer region near the film hole. The averaged heat transfer coefficient increases with the increase of injection angle.

FeTe1-xSex monolayer films： towards the realization of high-temperature connate topological superconductivity

We performed angle-resolved photoemission spectroscopy studies on a series of FeTe_(1-x)Se_x monolayer films grown on Sr TiO_3.The superconductivity of the films is robust and rather insensitive to the variations of the band position and effective mass caused by the substitution of Se by Te.However,the band gap between the electron-and hole-like bands at the Brillouin zone center decreases towards band inversion and parity exchange,which drive the system to a nontrivial topological state predicted by theoretical calculations.Our results provide a clear experimental indication that the FeTe_(1-x)Se_x monolayer materials are high-temperature connate topological superconductors in which band topology and superconductivity are integrated intrinsically.

Selective and localized laser annealing effect for high- performance flexible multilayer MoS2 thin-film transistors

We report the use of ultra-short, pulsed-laser annealed Ti/Au contacts to enhance the performance of multilayer MoS2 field effect transistors （FETs） on flexible plastic substrates without thermal damage. An analysis of the temperature distribution, based on finite difference methods, enabled understanding of the compatibility of our picosecond laser annealing for flexible poly（ethylene naphthalate） （PEN） substrates with low thermal budget （〈 200 ℃）. The reduced contact resistance after laser annealing provided a significant improvement in transistor performance including higher peak field-effect mobility （from 24.84 to 44.84 cm2-V-l.s-1）, increased output resistance （0.42 MΩ at Vgs- Vth = 20 V, a three-fold increase）, a six-fold increase in the self-gain, and decreased sub- threshold swing. Transmission electron microscopy analysis and current-voltage measurements suggested that the reduced contact resistance resulted from the decrease of Schottky barrier width at the MoS2-metal junction. These results demonstrate that selective contact laser annealing is an attractive technology for fabricating low-resistivity metal-semiconductor junctions, providing important implications for the application of high-performance two-dimensional semicon- ductor FETs in flexible electronics.

Effects of Nanostructured Back Reflectors on the External Quantum Efficiency in Thin Film Solar Cells

Hydrogenated amorphous Si （a-Si：H） is a promising material for photovoltaic applications due to its low cost, high abundance, long lifetime, and non-toxicity. We demonstrate a device designed to investigate the effect of nanostructured back reflectors on quantum efficiency in photovoltaic devices. We adopt a superstrate configuration so that we may use conventional industrial light trapping strategies for thin film solar cells as a reference for comparison. We controlled the nanostructure parameters via a wafer-scale self-assembly technique and systematically studied the relation between nanostructure size and photocurrent generation. The gain/loss transition at short wavelengths showed red-shifts with decreasing nanostructure scale. In the infrared region the nanostructured back reflector shows large photocurrent enhancement with a modified feature scale. This device geometry is a useful archetype for investigating absorption enhancement by nanostructures.