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A series of long-afterglow luminescent materials (SrAl2O4: Eu2+ (SAOE), SrAl2O4: Eu2+, Dy3+ (SAOED) and SrAl2O4: Eu2+, Dy3+, Gd3+ (SAOEDG)) was synthesized via the combustion method. Temperature and concentration control experiments were conducted on these materials to determine the optimal reaction temperature and ion doping concentration for each sample. The crystal structure and luminescent properties were analyzed via X-ray diffraction (XRD), photoluminescence (PL), and afterglow attenuation curves. The outcomes demonstrate that the kind of crystal structure and the location of the emission peak were unaffected by the addition of ions. The addition of Eu2+ to the matrix’s lattice caused a broad green emission with a central wavelength of 508 nm, which was attributed to the characteristic 4f65d1 to 4f7 electronic dipole, which allowed the transition of Eu2+ ions. While acting as sensitizers, Dy3+ and Gd3+ could produce holes to create a trap energy level, which served as an electron trap center to catch some of the electrons produced by the excitation of Eu2+ but did not itself emit light. After excitation ceased, this allowed them to gently transition to the ground state to produce long-afterglow luminescence. It was observed that with the addition of sensitizer ions, the luminous intensity of the sample increased, and the afterglow duration lengthened. The elemental structure and valence states of the doped ions were determined with an X-ray photoelectron spectrometer (XPS). Scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDX) were used to characterize the samples. The results show that the sample was synthesized successfully, and the type and content of ions in the fluorescent powder could be determined. The fluorescence lifetime, quantum yield, bandgap value, afterglow decay time, and coordinate position in the coherent infrared energy (CIE) diagram of the three best sample groups were then analyzed and compared. Combining the prepared phosphor with ink provides a new idea and method for the field of anti-counterfeiting through screen printing.

Green emitting long afterglow phosphor SrAl2O4: Eu2+, Dy3+ was synthesized via the combustion method. The physical phase analysis was carried out by X-ray diffraction, the results show that the introduction of Eu2+ into the lattice of the matrix resulted in a broad green emission centered at 508 nm, which is ascribed to the characteristic 4f65d1 to 4f7 electronic dipole allowed transition of Eu2+ ions. The doping of Eu2+ and Dy3+ did not change the physical phase of the crystals. Dy3+, as a coactivator, does not emit light itself, but can generate holes to form a trap energy level, which acts as an electron trap center to capture some of the electrons generated by the excitation of Eu2+. After excitation has ceased, let them gradually to transfer to the ground state for long afterglow luminescence. Then, we investigate the optical characterizations of different samples excited by X-ray. We found that SrAl2O4: Eu2+, 0.5% Dy3+ has this higher luminous intensity and afterglow. Its fluorescence lifetime is about 720 ns, and its quantum yield can reach 15.18%. Through search engine marketing (SEM) and energy dispersive X-ray spectroscopy (EDX), it has been proved that the sample has been successfully synthesized and its component content has been confirmed. The Eg value calculated from the diffuse reflectance spectrum is 4.61eV. The prepared SrAl2O4: Eu2+, Dy3+ luminescent powder is combined with Polydimethylsiloxane substrate for anticounterfeiting application, which provides a novel idea and method for the development of the anticounterfeiting field.

A simple and novel method for the deposition of polypyrrole (PPy) and cellulose nanocrystal (CNC) composites on different fiber substrates by reactive ink-jet printing was proposed. PPy/CNCs composites were successfully prepared, and the surface resistance of conductive layer deposited on different fiber substrates is the least when the monomer concentration is 0.6 M. PPy/CNCs were deposited on polyethylene terephthalate (PET) to form a conductive layer by adding polyvinyl alcohol (PVA), and the optimum sintering temperature is 100 °C (monomer/PVA ratio 4.0, conductivity 0.769 S cm−1). The PPy/CNCs conductive layer deposited on the paper has the lowest surface resistance and the best adhesion, and the surface resistance of PPy/CNCs conductive layer decreases first and then increases with the increase of sulfonate concentration. Moreover, the volume of anion in sulfonate will affect the arrangement and aggregation of PPy molecular chain in composite materials. Appropriate sulfonate doping can improve the conductivity and stability of conductive paper, and the maximum conductivity is 0.813 S cm−1. Three devices based on PPy/CNCs conductive paper were proposed and fabricated. Therefore, this ink-jet printing provides a new method for the preparation of conductive materials, sensors, energy storage and electromagnetic shielding, etc.

N owadays, medical plastic gloves are sorted into the left and the right hands manually with low efficiency during productive process. In this paper, an automated way is proposed to improve this situation through establishing a convolutional neural network model for image recognition. The back propagation process of learning and training is analyzed in order to optimize the weight by adopting the combination of different activation layers and different loss functions. For the same learning times, there are two evaluation indexes. One is the result of recognition accuracy in the training set, the other is the convergence curve and oscillation amplitude of the loss function. Finally, the adaptability of the combinations is discussed, which plays an important role in improving the recognition accuracy of the left and the right hand.

By focusing on the greening of glass packaging, the whole life cycle of glass packaging is analyzed in this paper, the pollution and consumption resources and energy in the production, circulation, use and recovery of glass packaging are enumerated in the way of checklist, and in the end, the influences of each stage on environment and human body are achieved. The list shows that the most influential link to the environment and human body is the manufacturing and recycling of products, which will consume a large amount of water, electricity and fuel resources, while a large amount of gases containing C, N and S in the emissions will lead to the greenhouse effect, the waste water containing P, N and S will lead to eutrophication of the water body, and the dust will lead to respiratory diseases and so on. In order to solve these problems, this paper puts forward the countermeasures of green glass packaging—light weight treatment of bottle body—to refill glass packaging and recycle broken glass according to the principle of 3R1D of green packaging. This will play a guiding role in promoting energy-saving and emission reduction and environmental sustainable development in packaging industry.

The main direction of this paper is visualization of post-press equipment. Through interaction of three kinds of modeling software, the model interface are studied. This paper proposed a technical method in order to realize the virtual reality display effect based on conventional modeling software. Taking the virtual reality display of the self-designed knife folding machine as an example, using FEM to analyze the stress and deformation of paper and display the fault. The interaction of three modeling software is enhanced, and this method is verified valuable.

Character recognition is vital to character quality inspection on the surface of car handles. In order to solve the problem of characters with unfixed scales, rotation, and gray changes, we propose a car handle character recognition algorithm based on support vector machine and circular projection. Firstly, the algorithm binarizes car handle character image to eliminate the influence of grayscale changes. Secondly, according to the principle of the circular projection matching algorithm, equidistant circles are applied to extract the feature about the number of pixels within the minimum circumscribed circle of the character. Finally, a new character feature similarity measure function is introduced and combined with support vector machines to recognize the car handle characters. After being tested, the handle recognition characters with arbitrary rotation angles and scale changes in the range between 1 to 1.5 times, the algorithm recognition accuracy reached 98%.

For the traditional design problems of printing press, the finite element analysis technology is introduced to the field of printing machine design. One three-dimensional parametric modelling software such as Pro/Engineer Wildfire is used to model the press roller drive gear. Firstly, the load distribution of a single tooth of press roller driving gear is analyzed, and then the stress and strain for the three-dimensional model are calculated, the detailed calculated results and the analyzing charts are got by ANSYS, one finite element analysis software. The calculated results show that, when the press roller drive gear is forced, the tooth root and the half round of ring mounting hole force become large. So, an improvement measures is put forward. The re-analyzed results show that the improvements in the design of stress and strain are less than the original design. It takes a guiding role in the design of the other printing gear, and makes a foundation in the further optimization design.