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Plant Growth and Photosynthetic Characteristics of Soybean Seedlings Under Different LED Lighting Quality Conditions
摘要： Light-emitting diodes (LEDs) have recently been widely used as light sources for the cultivation of plants in controlled environments. However, before LEDs can be used as the sole light source, it is imperative that soybean (Glycine max) response to light quality be well characterized. The objective of the present work was to investigate how soybean seedlings respond to different blue (B) and red (R) photon flux ratios (PFR) using LEDs. Light treatments were comprised of 170 ± 5 μmol m?2 s?1 photosynthetic photon flux density with B:R ratios of 0B:100R%, 10B:90R%, 25B:75R%, 50B:50R%, 80B:20R%, 90B:10R%, and 100B:0R%. Our results suggest that with the increase in B PFR from 0 to 90%, both plant height and specific leaf area inclined to decline while stem diameter gradually increased. The plants exposed to 80B:20R% showed unexpectedly greater total root length, root surface area, root volume, number of root tip, plant dry mass, leaf dry mass, root dry mass, leaf mass fraction and root mass fraction than plants exposed to all other treatments. Plants grown with 0B:100R% had the highest content of chlorophyll b (Chl b) and content of total chlorophyll [Chl (a + b)] but possessed the lowest ratio of the content of chlorophyll a to the content of chlorophyll b (Chl a/b). Plants grown with R alone also showed the lowest chlorophyll fluorescent parameters. The light-saturated CO2 assimilation rate (Asat) and the light-saturated stomatal conductance (gssat) for 0B:100R% were, respectively, 64.85% and 203.23% lower than those for 80B:20R%. However, plants grown with sole R accumulated higher soluble sugar and starch content during the daytime. Collectively, our results suggest that compared to R- or B-LED alone, an appropriate combination of R and B promotes plant growth and photosynthetic performance for soybean.
关键词： Soybean,Plant growth,Light quality,Photosynthetic characteristics,LED
更新于2025-09-23 15:21:01
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Enhanced efficiency in dye-sensitized solar cell by localized surface plasmon resonance effect of gold nanoparticles
摘要： Strong localized surface plasmon resonance (LSPR) ˉeld, which is generated from gold nanoparticles, may enhance photons absorption of dyes in dye-sensitized solar cells (DSSCs), resulting in the improvement of their power conversion e±ciency (PCE). In this paper, we report the incorporation of oleylamine capped gold nanoparticles (AuOA NPs) into the N-719 dye layer in DSSCs. The cells were prepared by varying the weight percentage of AuOA NPs with respect to the dye weight in dye solutions. The dye solutions containing 1.44 wt.%, 1.92 wt.% and 2.4 wt.% of AuOA NPs exhibited an enhancement in their absorption spectra in the UV-Visible range, which may be the result of the excitation of localized SPR. The J (cid:1) V characteristics of those DSSCs show an enhancement in their photocurrent along with their PCE, from 4.18% to 5.14% for the cells made from the dye solutions without AuOA and with addition of 2.4 wt.% of AuOA, respectively. This improvement is due to the enhancement of light absorption and hence charge carrier generation by the Plasmonic wave generated by AuOA NPs through the LSPR phenomenon.
关键词： gold nanoparticles,impedance spectroscopy,localized surface plasmon resonance,J (cid:1) V characteristics,Dye-sensitized solar cells
更新于2025-09-23 15:21:01
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Nanoplasmonics || Plasmonic Nanoantenna Array Design
摘要： Recently, wireless optical communication system is developing toward the chip level. Optical nanoantenna array in optical communication system is the key component for radiating and receiving light. In this chapter, we propose a sub-wavelength plasmonic nanoantenna with high gain operating at the standard optical communication wavelength of 1550 nm. The designed plasmonic antenna has a good matching with the silicon waveguide in a wide band, and light is fed from the bottom of the nanoantenna via the silicon waveguide. Furthermore, we design two kinds of antenna arrays with the proposed plasmonic nanoantenna, including one- and two-dimensional arrays (1 × 8 and 8 × 8). The radiation characteristics of the antenna arrays are investigated and both arrays have high gains and wide beam steering range without grating lobes.
关键词： localized surface plasmon,radiation characteristics,integrated photonic devices,plasmonic nanoantenna,integrated optical antenna arrays
更新于2025-09-23 15:21:01
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New cyclic and acyclic imidazole-based sensitizers for achieving highly efficient photoanodes for dye-sensitized solar cells by potential assisted method
摘要： A series of systematically tailored aryl acyclic (biphenyl, dye 1 and 2) and cyclic (phenanthrene, dye 3 and 4) and methyl-substituted (dye 5) imidazole derivatives were synthesized and characterized for dye-sensitized solar cells (DSSCs) application. Anisole ancillary donor was attached to -NH position in the imidazole center to obtain dye 2 and 4. Cyclic voltammetry and UV-visible studies of all the dyes indicate their suitability for DSSC application. Among the synthesized dyes, dye 4 having phenanthrene donor and anisole ancillary donor showed highest power conversion efficiency (PCE) of 7.16% (JSC = 13.07 mA/cm2, VOC = 0.831 V, FF = 0.659). Dye 2 displayed the highest electron lifetime in the conduction band of photoanode and hence the open circuit voltage of DSSC based on dye 2 was highest among the dyes studied (0.865 V). By using a novel potential assisted dye staining process, the dye loading on the photoanode is enhanced by 18% in 1h, which in turn enhanced the PCE to 8.10%.
关键词： DSSC,J-V characteristics,Imidazole,Phenanthrene,IPCE,Biphenyl
更新于2025-09-23 15:21:01
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The influence of substrate tilt angle on the morphology of laser cladding layer
摘要： Laser cladding technology has been increasingly used in processes of mechanical part and component repairing and remanufacturing. However, current research on the morphology of laser cladding is carried out on the premise of substrate level, it cannot be directly applied to the inclined substrate for laser cladding. This paper studied the influence law of tilt angle on the morphology of laser cladding through geometric parameters and profile of the laser cladding. Results show that substrate tilt angle mainly affects five geometric parameters such as the width and height of the layer cladding, peak shift, elevation side width and reduction side width. And a theoretical model for these geometrical parameters has been established for prediction in this paper. Meanwhile experimental profiles of laser cladding results verified the consistency between the laboratory data and model predictions, which is developed for tilted substrates. It will greatly expand the application range of laser cladding technology on complex parts such as gears.
关键词： Inclined substrate,Theoretical model,Layer geometric characteristics,Coaxial powder feeding,Laser cladding
更新于2025-09-23 15:21:01
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[Laser Institute of America ICALEO?? 2016: 35th International Congress on Applications of Lasers & Electro-Optics - San Diego, California, USA (October 16a??20, 2016)] International Congress on Applications of Lasers & Electro-Optics - Investigation of ablation characteristics for microrobotic materials using laser machining
摘要： Microrobotic devices have been widely investigated as promising alternatives to conventional biomedical technologies. By utilizing magnetic materials, microrobotic devices can be wirelessly manipulated by external magnetic fields without the use of additional power transfer units or batteries. Thus, the overall structures of the microrobotic devices can be effectively minimized to be applied for the human body. To manipulate the devices, various methods such as a magnetic force-based pulling method, cilia-like beating method, and helical propulsion method have been proposed. Conventional helical microrobotic devices have generally been manufactured by using three-dimensional (3D) printing technologies. These technologies are useful when manufacturing spatially complex structures such as the helical structures. However, due to the limitations of the extrusion and lamination processes, microrobotic devices can be constructed with low degree of precision and can have poor surface roughness under the 3D printing technologies. This may cause undesirable damages to the human body tissues. Furthermore, 3D printing requires long processing time due to post-processing to remove unwanted body parts. To improve surface quality and shorten processing time, this research uses laser machining technology. Before directly applying to fabricate helical microrobotic devices, laser ablation characteristics on Acrylonitrile Butadiene Styrene (ABS), which is a common material used for 3D printing, are investigated.
关键词： Acrylonitrile Butadiene Styrene (ABS),ablation characteristics,3D printing,laser machining,microrobotic devices
更新于2025-09-23 15:21:01
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A Novel Inverse Analysis Method to Identify Concentration and Current Density Distributions on Electrode Surface
摘要： A novel method to identify accurate polarization characteristics for a concentration-dependent electrochemical reaction was developed. This method identifies polarization characteristics which are dependent on concentration on electrode surface of a flow cell. Since the concentration on the electrode surface sitting in a flow cell cannot be measured directly, inverse analysis approach is applied. As the observation information of this inverse problem, total currents on the electrode are measured with different bulk concentration. The unknown polarization characteristics are expressed with piecewise linear function with unknown parameters. The relationship between observation and unknown parameters are modeled with advection-diffusion equation. The fluid velocity field of the flow cell is modeled with Navier-Stokes equation. These equations are discretized by finite volume method. In order to validate the proposed method, identification using both numerically generated data and experimental data were performed. The validation result demonstrated the good accuracy of the method.
关键词： inverse analysis,concentration distribution,electrochemical flow cell,current density distribution,polarization characteristics
更新于2025-09-23 15:21:01
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Hydrogen Sensing Characteristics of AlGaInP/InGaAs Complementary Co-Integrated Pseudomorphic Doping-Channel Field-Effect Transistors
摘要： In this article, the hydrogen sensing device and logic characteristics of the Al0.25Ga0.25In0.5P/In0.1Ga0.9As complementary co-integrated pseudomorphic doping-channel ?eld-effect transistors are demonstrated. Due to the existence of a relatively large conduction (valence) band discontinuity at Al0.25Ga0.25In0.5P/In0.1Ga0.9As heterojunction and the employment of a small energy-gap In0.1Ga0.9As channel layer, it could provide a high gate barrier height to avoid electrons (holes) injection form channel into gate region in the studied n-channel (p-channel) device. With respect to the n-channel (p-channel) transistor under hydrogen ambient, hydrogen molecules are adsorbed and dissociated on the Pd catalytic metal surface, followed by rapid diffusion of hydrogen atoms into the MS interface where the dipoles are formed to lower (elevate) the gate barrier height and enhance (decrease) the drain current. In the n-channel (p-channel) device, the threshold voltages at drain current of 0.1 mA/mm are of 0.67 (0.05) and 0.38 (?0.26) V in air and at hydrogen concentration of 9800 ppm, respectively. As hydrogen is detected, the characteristics of inverters shift left obviously, and the VOH and VIH values are decreased.
关键词： field-effect transistors,hydrogen sensing,AlGaInP/InGaAs,logic characteristics
更新于2025-09-23 15:21:01
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The application of image analysis technology in the extraction of human body feature parameters
摘要： With the improvement of living standards, personalized clothing customization has become a trend of people’s apparel demand. The key factor in personalized clothing customization is a three-dimensional human modeling. With the development of image analysis technology, it is possible to use image analysis technology to extract human characteristics. In this paper, two-dimensional human feature regions and characteristic parameter extraction methods of images are used. The backpropagation neural network (BP neural network) is used to curve the three-dimensional human characteristics, and the neck, chest, waist, and buttocks of 22 subjects are verified. The results show that the use of this method can well achieve the extraction of human characteristic parameters.
关键词： Human characteristics,BP neural network,Image analysis,Feature extraction,Computer-aided design (CAD)
更新于2025-09-23 15:21:01
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Research and Modeling of Photovoltaic Array Channel Noise Characteristics
摘要： The photovoltaic array can be used as a medium for carrier communication to realize monitoring of photovoltaic components. Photovoltaic array channel noise, especially the pulse-type noise therein, seriously interferes carrier communication, so it is necessary to grasp the characteristics of the photovoltaic array channel noise. Photovoltaic array channel noise modeling is a key process when conducting anti-noise immunity tests of monitoring equipment. Based on the time-domain waveform of photovoltaic series channel noise which is measured in a photovoltaic power station, this paper proposes a photovoltaic array noise modeling method of Wavelet Peak-Type Markov chain, and studies the in?uence on modeling accuracy when different mother wavelets are adopted for modeling. From the simulation results, root mean square errors of the predicted output for Haar, Biorthogonal and Daubechies wavelet-based function modeling case are 0.9614 V, 1.4915 V and 0.7928 V, respectively, validating that Daubechies wavelet-based function is the best wavelet-based function of modeling. In the case that the peak of original noise reaches 20 V, the predicted mean absolute error of this model is only 0.4926 V, which not only veri?es the applicability of the Wavelet Peak-Type Markov chain model to the photovoltaic array channel noise, but also veri?es the applicability to the pulse-type noise.
关键词： photovoltaic array channel noise,noise characteristics and modeling,wavelet packet decomposition and recombination,Peak-Type Markov chain
更新于2025-09-23 15:21:01