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This study purposes to investigate acoustic absorbing and puncture resisting properties of wall covering composites with different number of layers, and then to construct prediction model of acoustic absorption coefficient. Puncture resistance linearly increases but maximum absorption coefficient shifts to lower frequency with number of layers.The acoustic absorbing property of wall covering composites presents porous acoustic-absorbing characteristic, and its prediction model correlates with critical frequency and maximum absorption coefficient. The resulting coverings have excellent puncture resistance and acoustic absorbing properties.

As technology expands rapidly, scientific productions have become an indispensable part for human daily life. Hence, human begin to value environment comfort and functional property. This study purposes to add reinforcing materials, carbon fiber and glass fiber, into polyurethane (PU) foam solvent, and to form PU foam composite board after foaming and curing process. The foaming density and reinforcing fiber were altered during process. The burst strength, acoustic absorption and thermal conductivity of resulting organic/inorganic fiber-reinforced PU composite foam boards were evaluated. Result displays that, 5 wt% additions of carbon fibers improved burst strength and thermal insulation, and maintained the original acoustic absorbing characteristic.

With increase of life quality, demand for surrounding environment becomes more and more severely. Noise pollution in daily life lowers comfortablility and quiet of life. It is reduced accordingly if effective utilization of sound absorbing materials. This study uses polyester (PET) fibers and Nylon fibers bended with PP fibers respectively to form PET/PP and Nylon/PP nonwoven fabrics and then thermally bonded preparing PET/PP and Nylon/PP composites. The optimal parameters are evaluated by mechanical strength, and sound absorption tests. This study expects to prepare sound-absorbing composites in application of automotive interior and indoor building wall. Nylon/PP composites prepared in this study have the optimum sound absorption coefficient of 0.4 at high frequency, when containing 10 wt% proportions of PP fibers.

Logistics industry becomes the mainstream with promotion of life quality. The selection of delivery type and aging is subjected to limitations of packaging materials. In order to protect from product’s damage, this study purposes to use recycled high-strength fibers, including high-strength PET fiber, and Kevlar fibers, and thermal bonding PET fiber as well as glass fabric forming needle-punched 3D composite. For comparison of varying reinforcement on mechanical property, thermal bonding and water polyurethane impregnation are used to reinforce the 3D composite which is composed of nonwoven fabrics and glass fabrics. Result shows that, mechanical property from water polyurethane impregnation displayed much higher than that from thermal bonding. Thermal bonding remarkably improved burst strength and static puncture resistance. Therefore, 3D composite impregnated with water polyurethane reaches higher puncture protection level.

Desulfurization of thiophene from model gasoline was carried out by using large charge number metal (Bi, Sb, Zr and Ru) ion modified NH4Y-zeolite by batch method. The sulfur uptake increased in the order of HY (0.85 mg/g) < BiY-1 (1.06 mg/g) < SbY-1(1.24 mg/g) < ZrY-1 (1.25 mg/g) < RuY-1 (1.35 mg/g). Sulfur uptake was influenced by Ru contentof RuY, which increased in the order of RuY-0.25 (1.11mg/g) < RuY-1 (1.41mg/g) < RuY-0.5 (1.68 mg/g). Sulfur removal was influenced by aromatics of model gasoline, i.e., sulfur removal of RuY-0.5 (42%) showed higher selectivity for thiophene than CeY-1 (24%) ones when model gasoline with toluene.

After years of stable operation, a group enterprise equity management information system has accumulated a large amount of historical operating data. At present, the enterprise operating situation analysis is primarily based on statistical inquiry, so we cannot find out the operational decisions information which includes future trends among the data, and that information are often deeply hidden. In this paper, the decision tree applying to the situation classification prediction is presented, including the construction of a professional field data warehouse, data preprocessing and discretization, decision tree algorithm and tree pruning optimization algorithm using weights. Through the experiment, the prediction accuracy may reach 95.8%. By use of enterprise operating situation analysis based on data mining technology, we can find out useful information for the enterprise management decision, strengthen the correct judgment in marketing operation and other aspects, thereby enhancing the market competitiveness.

This paper introduces the research on the beneficiation of a low-grade barite ore taken from Myanmar.Through the analysis of the ore properties and research on the flotation experiment, the optimum flotation conditions are determinedwhile the ore sample assays 64.32% BaSO4.Under the flotation conditions of the grinding fineness-200 meshes 80%, sodium oleate 800g / t and sodium silicate 500 g / t, “two-time roughing,one closed cleaningand open in the second cleaning operations” is applied, and two marketable barite concentrates can be obtained. The concentrate 1 and 2 contain 96.32% and 91.26%BaSO4 at the recoveries of 91.94% and 5.25%, respectively.

Recently, room temperature ionic liquids (RTILs) have been widely used in dissolution, homogeneous modification of cellulose. Cellulose only could be dissolved in RTILs at elevated temperature. Herein, effect of dissolution condition on microcrystalline cellulose in 1-butyl-3-methylimidazolium chloride ([Bmim]Cl) ionic liquid was studied. The results indicated that the degree of polymerization (DP) of regenerated cellulose decreased from 161 to 83 with the increasing of dissolution temperature in the range of 70 °C to 110 °C, whereas the DP was affected by dissolution time slightly. Moreover, after dissolution [Bmim]Cl could be recycled by distillation and vacuum drying. The recycled [Bmim]Cl also had good dissolving capability of cellulose, and its FTIR spectra was similar to that of original [Bmim]Cl.

At present, MD5 algorithm is commonly used in the file transfer system to conduct the tests of file integrity, but when a file is too large, it will take a long time to generate MD5 code for the whole file, with the result of reducing the transmission efficiency of the file. Based on this conduction, a fast algorithm of file integrity detection is provided, which can generate MD5 code with the file size and some random content of the file. Although the algorithm cannot test files roundly, it is integrated into the file transfer system. The test results show that this algorithm can detect the file integrity faster, and when the file is damaged or tampered with, the probability of detecting changes of the file content is higher than the theoretical value. The algorithm has great value in engineering applications.

This paper elaborates the beneficiation methods of barite, flotation reagents and different types of mineral processing of barite.

With the rapid development of DOA (direction-of-arrival) estimation methods, the existing beamforming technologies still have the problem of a way to balance high spatial resolution and robust performance. The aperture extension characteristics of fourth-order cumulants is used to raise the spatial resolution of the array in this paper. By using the structure of minimum redundancy array, the calculation of the fourth-order cumulants matrix can be reduced. Simulations of the properties of fourth–order cumulants beamforming method are analyzed in this paper, including the resolution analysis, multi-sources analysis and error analysis. Simulation results show that the fourth-order cumulants beamforming method has a higher spatial resolution than the conventional beamforming method without increasing the number of the array sensors.

s. Situated in Honghe Municipality of China, a magnetite-bearing cassiterite ore deposit is characterized by iron and tin minerals association in the oxide ores. Magnetite is the main iron mineral containing fine-sized cassiterite that should be recovered. Except for the complex mineral composition, the valuable minerals are finely disseminated in the ore, a joint process of magnetic and gravity concentration was used to process the ore. Results show that, a tin concentrate and a tin middlings can be obtained in processing the tailings of Low-intensity magnetic separation (LIMS), assaying 31.76% Sn and 1.98% Sn at the recovery of 46.18% and 13.36% respectively. The results provide some valuable reference in utilization of the tailings of the ore.

Research on beneficiation of a barite ore was conducted according to the properties of the ore. The gravity preconcentration and flotation experiments were carried out. The results showed that direct flotation is the better way to concentrate the valuable mineral without the gravity preconcentration. The flotation results show that a barite concentrate assaying 98.21% BaSO4 can be obtained with the recovery of 80.71%. The agent used in the flotation is water glass as depressant at 500 g/t, sodium oleate as collector at 700 g/t. In the closed circuit, one rougher, three cleanings and one scavenging operations were employed.

In recent years, as global technical progress grows, many mechanized machines are developed continuously. Mechanization has substituted for manpower in many factories for promotion of production efficiency, leading to mechanical noise happening more severely. If people are subjected to noise pollution for long term, they would happen dysphoria and absent mindedness, resulting in accident occurrence. Therefore, how to effectively reduce noise pollution becomes an urgent subject. Moreover, rapid population development and fast-growth economy raise consumption in every country, driving industry into high-production and high-consumption times and meanwhile generating much of wastes. In order to achieve sustainable development, these wastes should be recycled effectively. Therefore, 20 wt% recycled PET fibers were added in this study. This paper mainly used 3D and 15D Nylon fibers (70, 60, 50, 40, 30 wt%), low-melting PET fibers (10, 20, 30, 40, 50 wt%) and 20 wt% high-strength PET fibers, to fabricate Nylon 6/Low melting PET/ Recycled high-strength PET nonwoven via needle-punching process. After that, tensile strength, air permeability and sound absorption coefficient property of resulting nonwoven were tested and then evaluated respectively.

A single frequency network (SFN) based on the DTMB (Digital Television Terrestrial Broadcasting System) terrestrial digital television (DTV) system normally causes interference among signals from multiple transmitters in the network. These transmitters should broadcast the same program at the same frequency simultaneously in the service area. To meet the SFN network construction requirements in complex transport situation, TS distribution networks synchronization is one of the most important foundations. A design was proposed to insert into each MPEG-TS (SIP) packet with one absolute timestamp in the SFN adapter, which was proved to be valuable insuring the synchronization of the SFN TS distribution through field-test in Ningxia DTMB network.

Global warming increases each day and causes people to pay more attention to the reduction of carbon dioxide emission in order to mitigate the increase in temperature. Reducing, reusing, and recycling can effectively reduce the emission of carbon dioxide, to attain goals of energy conservation and carbon reduction. This study aims to explore the difference in the punch resistance and impact strength between the polyethylene terephthalate (PET) nonwoven fabrics and PET/TPU honeycomb grid/PET (P/T/P) composites. Recycle PET, high strength PET, and low melting PET are made into PET nonwoven fabrics, two layers of which are laminated with a TPU honeycomb grid, the interlayer, to form P/T/P composites. The constant rate puncture resistance, dynamic puncture resistance, and impact strength of PET nonwoven fabrics and P/T/P composites are evaluated. The experiment results show that both the constant rate and dynamic puncture resistances of P/T/P composites are lower than those of PET nonwoven fabrics.

As improvement of industry and society, some potential crisis happened in working and living environment is taken into account by human people. Meanwhile, different kinds of protective appliances develop rapidly, and composite boards with cushion and puncture-resistance property are required consequently. This study aims to develop a cushion/puncture-resistance PU foam protective composites. This paper used Polyol and Isocyanate to prepare porous PU foam composite via foaming and curing process. By changing foam density and addition amount, cushion and puncture-resistance property were tested and then evaluated to seek for PU foam composite with cushion and puncture-resistance property. Result shows that, when density was 80 kg/m3, PU foaming composite board had the optimum resilience rate of 44 %, lowest impact remaining load of 638 N and best puncture-resistance force of 138.3 N.

A new HDMI data transmission system is proposed in this paper. To achieve a better data transmission performance, the TMDS codec algorithm of HDMI transmitter and receiver are optimized, thus the precision and practical applicability is improved. Moreover, a color enhanced module and an error correction module are added to the system. The proposed system is implemented using Verilog DHL language and simulated in Modelsim software. The simulation results show that the proposed system exhibits better performance on the functions of data sending and receiving.

This study is to investigate the beneficiating possibility of a low grade lead ore in Yunnan by current mineral processing technology. A low grade lead ore sample assaying 1.14%Pb and 5.72g/t Ag was used in tests. In the experiment, gravity pre-concentration to discard the tailings and the effects of grinding fineness, types and dosages of reagents in roughing were investigated. On the basis on optimum condition of roughing, a close circuit flowsheet was put forward. A lead concentrate assaying 47.02% Pb and 192.36g/t Ag was obtained with the recovery 73.59% and 65.12%, respectively. It gives some valuable information for the Owner in making a decision in utilization the ore economically.

The dynamic puncture resistance of multi-layer integrated composite which was comprised of glass fabric reinforcement or Kevlar fabric reinforcement and nonwovens were discussed as related to recycled Kevlar fibers amount, number of layer and K-ply position for purpose of cost reduction and performance improvement. The result shows that, 20 wt% Kevlar fibers contained in nonwovens have the optimum puncture resistance. And the dynamic puncture force increases linearly with number of layers, and also improves proportionally as increasing number of K-ply. The resultant multi-layer composite is expected to be used as body armor interlayer and packaging materials.

Hemostasis is the critical steps for trauma and emergency. When injured person is under circumstance of hemorrhage, the important step is immediate hemostasis because mild hemorrhage makes patient feeling pain and dizziness while abundant hemorrhage would lead to coma, shock even death. Therefore, hemostasis becomes an important rescue issue to bleeding patient. This study uses Polylactic acid (PLA) and Polyacrylate (HPA) to prepare PLA/HPA nonwoven fabric with different weight ratios of 100/0,95/5,90/10, 85/15, 80/20 wt%/wt%, following with discussions of tensile strength, tearing strength, softness, air permeability, water vapor transmittance, water absorption, water retention. The results show that, 80 wt%/20 wt% of PLA fiber and HPA fiber was the optimal blending ratio, and its water absorption, water retention and softness were respectively improved by 323 %, 245 % and 22.3 % by contrast with 100 wt%/0 wt% of PLA and HPA; but its tensile strength was decreased by 63 % even that still reaches the strength of absorbent cotton.

The compound fabrics comprised of double layers of nonwovens and carbon fabrics were prepared by needle-punching and thermal bonding techniques. The thermal bonding and number of layers effect on thermal insulating and sound absorbing property have been discussed. The resulting compound fabrics have thermal conductivity decreases to 0.02 W/(m*K) for single layer of thermo-bonded compound fabrics and sound-absorbing coefficient reaches to 0.848 at 4000 Hz for 3-layer un-thermo-bonded fabrics .

The effect of alkali treatment on excess sludge supernatant characteristics was studied in this experiment. 4 mol/L sodium hydroxide solution was utilized to adjust the initial pH value of excess sludge to 9.0, 11.0 and 13.0. Batch experiments were operated in 35 °C shaking bath for 12 h. The soluble chemical oxygen demand (SCOD), protein and polysaccharide concentration in excess sludge supernatant was measured every 3 h. The experimental results showed that maximum amount of protein, polysaccharide and SCOD were obtained when the initial pH value was 13.0.

The effect of Kevlar fibers amount, number of layers, thermal bonding and fabric type on constant-rate puncture resistance of low-cost compound fabrics are discussed. Therein, compound fabrics were prepared by nonwovens and woven fabric via needle-punching and thermal bonding processes. The result shows that, Kevlar fibers amount and number of layers are both positive to improvement of puncture resistance. And thermal bonding process increases the wearer safety of puncture-resistance materials. For different kinds of fabrics, compound Kevlar fabric shows the maximum puncture resistance.

Due to the different PV modules and external conditions, large-scale photovoltaic power plants often show a multi-peak PV characteristics. But the traditional MPPT methods is only for single-peak P-V curve to strike a maximum power point. So we need to improve the conventional MPPT methods. In the MATLAB/Simulink environment, we combined the Hysteresis Comparison Method with Incremental Conductance to build the S-function to create a simulation model obtaining the maximum power point power, voltage and current. In the same simulation system the traditional Incremental Conductance was used to obtain the maximum power, voltage and current which compare with the maximum power, voltage and current which obtained by the proposed method . The results of simulation illustrated the effectiveness of the proposed method .

A physics model was established for describing the particle size distribution of beryllium (Be) powder produced by impact attrition milling. In this model, two factors were considered: the first, the distribution of existing state of particles with different original kinetic energy should obey the Maxwell-Boltzmann statistics after impacted, it was that, being at higher energy level made big particles unstable, which were easy to be fractured into smaller pieces in impact attrition process, this influencing factor described as the negative exponential of particles size; the second, the tendency to remain low surface energy needed particles should keep big volume as much as possible, this effect defined as the cube of particles size. The actual particle size distribution of Be powder was resulted from the competition between these two factors. Calculating result from the model was in good agreement with data from measurement.

In this paper, an Ultra-wide-band (UWB) filter based on composite right/left handed transmission line (CRLH TL) is presented. The structure of the proposed band-pass filter is quite simple, of which the size is 0.5cm×1.5cm. Left-handed capacitor is obtained by couple of microstrip lines, and Left-handed inductance is obtained by the grounded stub. The simulated results indicate that the pass band of UWB filter is 3.4-11GHz, the insertion loss is less than 1 dB and the return loss is smaller than -12.5dB. The performance of UWB filter could meet the requirement of UWB communication systems.

We designed the H-shaped metamaterial which is used at terahertz frequencies, and it can suppress magnetic response and construct purely electrical resonance. The resonance behaviors and the impact of geometrical parameters of the H-shaped metamaterial were analyzed by using effective circuit model. The simulation results indicate that permittivity of H-shaped metamaterial is negative at terahertz frequencies. H-shaped metamaterial could be used widely in the design of terahertz devices due to its simple structure and easy manufacture.

In recent years, as quality life improves, people begin to focus on quiet environment. Long-term noise pollution makes trouble of dysphoria and concentrating for people, thus noise-reduction has become an urgent project. This study uses Nylon 6 fibers, blended with different contents of low-melting PET fibers (10 wt%, 20 wt%, 30 wt%, 40 wt% and 50 wt%), to fabricate Nylon6/ LPET nonwoven fabrics after needle-punching process. Afterwards, their maximum tensile strength, air permeability, sound absorption coefficient were all evaluated. When low-melting PET fibers contain 30 wt%, the nonwoven fabric has the better sound-absorbing property. Herein, the maximum tensile strength reaches 70.79 N and 31.01 N, respectively in CD and MD; the air permeability is about 116.5 [cm3/(cm2/s)]

Polylactic acid (PLA) is often applicable in biomedical because in environment it degrades into carbon dioxide and water. This study aims to prepare sandwich-structure PLA/ Tencel composite nonwoven, following by its property test for evaluating effect on wound dressing. In this study, PLA fibers, blended with Tencel fibers, were made into nonwoven fabrics based on nonwoven processing technology. After that, their tensile strength, tearing strength and softness were tested for evaluating nonwoven fabric properties. The result displays that, PLA nonwoven fabrics show higher tensile strength and tearing strength than Tencel nonwoven fabrics.

In recent years, as improvement of human living life, people begin to focus on themselves health. It is certain that bamboo charcoal has many properties, including water purification, deodorization, anion release and far-infrared ray radiation. This study aims to prepare PET/BC warp-knitted fabric composed of polyester yarn (PET) as warp yarn and bamboo charcoal polyamine yarn (BC) as weft yarn using Velcro Crochet Machine. Afterwards, air permeability, elastic resilience and far-infrared ray emissivity of resulting knitted fabric were discussed by changing weft yarn type. Result shows that, for knitted fabrics, weft yarn type cannot affect the elastic resilience; yet PET weft yarn makes air permeability decreasing.

Currently, all over countries call for greening the earth. Whereas, there is no enough space to be planted by developing countries, owing to their excessive and intensive development. For establishing green globe, every country expects to green forming urban forest in the way of soilless culture, attached with far-infrared fiber in order to promote root growing speed. This study uses polyester (PET) fiber and far-infrared PET (FIR) fiber to form PET/FIR composite nonwoven fabric by nonwoven processing technology. In this process, blending ratio of PET and FIR fibers was varied. Afterwards, moisture retention, air permeability and far-infrared emissivity of PET/FIR composite nonwoven fabric were all tested. The results show that, blending ratio of PET and FIR fibers has no significant influence on moisture retention and air permeability, but obviously impacts on far-infrared emissivity.