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Heavy metal zinc is one of the trace elements necessary to the growth of vegetable, but Zn excessiveness also could cause damage. In this research, four vegetables were planted by soil culture method under different Zn2+concentration controlled by the exogenous Zn2+addition; their growth characteristics were analyzed to find the sensitive growth indexes to Zn and compare their tolerance to Zn pollution. Results show that: low concentration of Zn2+(< 100 mg/kg) can promote significantly the plant height and the root length growth of all the four vegetables, while, as the exogenous Zn2+increased to the concentration of 150 mg/ kg, the number of leaves, the above-ground dry biomass and the underground dry biomass were suppressed significantly; in this experiment, the four vegetables appeared different sensitivity to Zn stress,Lactucasativavar.longifoliafappeared highest tolerance andBrassicachinensisappeared less sensitivity to Zn stress.

Water and steam quality during operation must be strictly controlled for ultra-supercritical unit. Changes of indicators in water and steam are supervised, water and steam quality and working condition of boiler water, as well as supervision of water and steam quality are reviewed in this paper. Risks of corrosion and scaling in Taishan power plant is assessed. As a result, control effect of TOC is remarkable in Taishan power plant, content of Cl- and SO42- can satisfy the control standard, that is , risk of corrosion and scaling is low. Dissolved oxygen is significantly exceeded in the condensate polishing desalination device , and there has risk of iron deposit. To convert the feed water treatment from AVT(All Volatile Treatment) to OT(Oxygenated Treatment) can solve the problems above .

In this research, a bi-criteria heuristic is proposed to find non-dominated solutions for scheduling unrelated parallel machines with release dates that minimizes makespan andtotal weighted tardiness.

In order to understand the sedimentary characteristics of shale and prospects of shale gas exploration in the lower Silurian Longmaxi Formation northern of Guizhou Province, outcrop and core observations, thin sections, X-ray diffraction analysis and other means are used. Studies show that the thickness of Longmaxi formation shale is generally large, range from 20m to 200m, mainly develop in the water shelf. The mineral mainly compose of detrital quartz and clay minerals, and five lithofacies can be identified: black shale, silty shale, carbonaceous shale, calcareous shale and argillaceous siltstone. Longmaxi shale kerogen type is mainlyIand II, and Ro value is average of 1.87%, mainly in the mature - over mature stage. In addition, the TOC content and gas content of Longmaxi shale is high, what’s more, these two parameters have good positive correlation. Compared with the Barnett shale, both of them have some similarities in the development environment shale, shale thickness and type of organic matter and TOC content, while, Longmaxi shale is deeply buried and post-destruction more intense. Longmaxi shale sedimentary environment is stable, high shale thickness and stable distribution, good quality source rocks and high brittle mineral content, which has meet the basic parameters of shale gas exploration and development, and has a large shale gas exploration potential in study area.

Mechanical properties of the electron beam weld zone, which are different from the base metal, of Hastelloy C-276 were studied by small punch test (SPT) technology. Load–displacement curves and material properties were obtained by using miniaturized plate-type specimens (3mm diameter×(0.15-0.4) mm thick) from the weld and base metal respectively. The result shows that the maximum load of weld is larger than that of the base metal under the same thickness, meaning the higher strength of the weld. Furthermore, finite element method analysis was performed to investigate the effects of specimen thickness, the diameter of loading ball and the diameter of center hole in holder on the plastic damage of Hastelloy C-276.

This paper describes several typical RFID privacy protection protocol security methods. To improve the security of RFID protocols, which proposed in the literature and some deficiencies, propose a new time-based hash chain function. The program can be effective against security issues, such as unauthorized reading, location tracking, eavesdropping, spoofing, replay and etc. The program applies to a higher number of tags and readers, with better security and efficiency.

The structure material corrosion in liquid lead or lead-bismuth eutectic (LBE) is a tremendous limitation of the development of lead cooled fast reactors and accelerator driven sub-critical system (ADS). Keeping a certain oxygen concentration can prevent the steel pipe from corrosion by LBE. Through dissolution and precipitation of PbO ceramic has been found to control the oxygen concentration successfully. This paper presents research on a new technology of processing lead oxide ceramic. The raw material, pure lead oxide powder and deionized water, without any other chemical substances, were dry-pressed, placed in sample holder and heated in household microwave oven. Compare with conventional sintered ceramics, the microwave sintered lead oxide ceramics show better density, greater hardness. The results show that this promising technique has distinguished characteristics of energy-saving, rapid processing and better hardness and microstructure.

With the advancement of industry, the utilization of cushion package to apply on the products of civilian, sports, electric, precise equipment increases extensively, which are brittle and vulnerable that need to be protected. In the research, the Recycled High Strength PET fiber, Recycled Kevlar fiber and low melting PET fiber are selected as materials, which the content of Recycled Kevlar fiber is stationary. The composite nonwoven fabric was manufactured by non-woven processing and subsequently estimated its stab-resistant strength and air permeability. The composite nonwoven fabric was being heat treatment which can make low melting point PET fiber bonding with other fibers in order to enhance the mechanical property of composite nonwoven fabric.

This study combines hydrophilic and soft Tencel®fibers and low-melting-point polylactic acid (LMPLA) fibers by needle-punching and hot press processes to form moisture-retentive and comfortable Tencel®/LMPLA composite nonwoven fabrics. Air permeability, water vapor transmission rate, softness, water content rate, and water loss rate tests are performed on the composite nonwoven fabrics. The experiment results show that when hot pressed at 130 and 150 °C, the Tencel®/LMPLA composite nonwoven fabrics have good water absorption, water retention, and softness, which can be concluded as successfully moisture-retentive and comfortable Tencel®/LMPLA composite nonwoven fabrics.

Excessive bleeding becomes a primary cause for war wound death, accident death and operative death. Therefore, decreasing the bleeding time and operation time were play an important role in the preoperative period. In this study, the Tencel® fiber and high absorbent fiber were used to produce high absorption composite nonwoven fabrics. As the result of experiment, the higher high absorption fiber that will create the high stiffness, in addition, the nonwoven has upper stiffness at cross direction. In wicking behavior, the composite nonwoven has about absorption water reach 14 g when the high absorption fiber was 50 wt%. The assessment of application for this study anticipated the resulted high absorption composite nonwoven fabrics to be used as hemostasis material to decrease the ratio of dead person on bleeding.

The present study aims to investigate the influence of Coring glass substrate temperature on the topography, deposition rate, crystal structure, optical, and electrical properties of ZnS thin films produced by magnetic radio frequency sputtering method. From plain view SEM micrographs, the pebble structure has shown in all ZnS thin films deposited at various substrate temperatures. Through higher substrate temperature, smaller ZnS grains can be obtained in the present study. From XRD analysis, ZnS thin film exhibits hexagonal Wurtzite structure. When thickness of ZnS thin film arrive 300nm, optical transmission rate can be above 85% regardless of substrate temperature and gets optical energy barrier of 3.9 eV. From electrical measurement, the variation of resistivity with temperature exhibits a linear relationship for ZnS thin film.

Considering time-vary in unit cost and imperfect quality in process, this study presents a genetic algorithm to deal with the production schedule and batch lot problem for a manufacturing system. Incorporating linearly and exponentially continuous unit production cost, we assume that defective items are reworked at a constant rate after regular production immediately. Not all of the defective items are reworked but a portion of them are scraped due to serious damage. Our objective is to minimize the expected value of total cost for this production system. A genetic algorithm with the chromosome of real number type to solve this problem is proposed. Standard GA operators are used to generate new populations. These populations are evaluated by a fitness function using the total cost of production scheme. An explicit procedure for obtaining an approximate solution is provided.

We have demonstrated several MZIs based on two spaced 3-dB LPFGs with different interference lengths in conventional SMFs fabricated in air by femtosecond laser pulses with the duration of 200 fs and the repetition rate of 250 kHz. Experimental results show that the average fringe spatial period increases with the resonance wavelength, while decreases with the interference length in approximately inverse proportion. The dominant cladding mode interfering with core mode has been calculated. The MZI sensitivity on temperature, refractive index and strain with a length of 16mm has also been investigated.

Mach-Zehnder interferometer formed by a pair of long period fiber gratings on single mode fiber is investigated as surrounding refractive index sensors. Interference fringes with bandwidth of 1.68 nm are induced by core mode and the excited cladding mode. High SRI sensitivity of 280.74 nm/RIU at 1437.74 nm in the range of 1.333 to 1.360 is achieved. Whilst the strain sensitivity (~0.33 nm/mε) and temperature response (~20.7 pm/°C) at 1428.64 nm are relatively low, which is superior in avoiding cross sensitivity in refractive index measurement.

Network booting is the process of booting a computer from a network rather than a local drive. In this paper, a novel intelligent network booting protocol is proposed. It extracts all the states of the clients from their booting requests to their normal operations, which is depicted with a finite state machine. Based on the protocol, an intelligent network booting system is implemented with distributed modules, where the maintenance of the network booting system is automated, such as the preparation of the virtual booting partition for the client, loading and passing the booting parameters, and so on. Experiments are carried out to prove the efficiency of the network booting system.

Kevlar® fiber has characteristics of thermostability, high modulus, low elongation, impact resistance, chemical resistance and high performance. Therefore, in this study Kevlar® fiber was used to reinforce the nonwoven fabrics. In this research, the content of the Kevlar® fiber was varied as 0 wt%, 5 wt%, 10 wt%, 20 wt%, and that of 15D PET fiber was changed as 70 wt%, 65 wt%, 60 wt%, 50 wt% accordingly when the Low-Tm polyester fibers was constant as 30 wt%. These fibers were used to manufacture the Kevlar®/PET composite nonwoven by nonwoven processing. Afterwards, the mechanical properties of the Kevlar®/PET composite nonwoven was measured both at cross direction and machine direction.

Polymer materials such as sodium alginate, chitosan, polylactic acid, and pectin, are commonly used as biomedical materials. This study combines sodium alginate (SA) and chitosan solutions to make the compound membranes. The compound membranes with optimal parameters are then combined with base fabrics, forming the compound dressings. SA and chitosan are mixed with various ratios, and then added with calcium chloride (CaCl2 (aq)), after which the mixture is thermally treated to form the SA/chitosan compound membranes. Moisture retention, swelling, weight loss, water contact angle, and water content ratio tests evaluate the resulting membranes, determining the optimum parameters. When the ratio of SA to chitosan is 7:3, the resulting membranes exhibit an optimal swelling. The weight loss of the membranes starts decreasing with the addition of CaCl2 (aq), indicating an increase in the structural stability of the compound membranes. Lastly, the water contact angle of all compound membranes is smaller than 90°, stating that they have a good hydrophilicity.

The high-strength polyester fiber is a kind of chemical fiber that is rapidly developed and widely applied. With development of technology, the demands for polyester fiber are becoming more and more. Furthermore, the high-strength polyester fiber, used to reinforce the matrix, has higher modulus and strength than commercial polyester fiber. In this research, the 15D polyester fiber, the low melting polyester and the high-strength polyester fiber were used to manufacture the high-strength PET compound nonwoven fabrics by nonwoven processing. Afterwards, the mechanical properties of the PET compound nonwoven was measured both at cross direction and machine direction.

High-temperature brazing molybdenum using palladium and titanium foils have been investigated in the experiment. Successful brazed joints are achieved from using the palladium filler foil. Brazed joints are fully dense and free of any intermetallic phase. Three point bending strengths of 246 and 233 MPa are obtained from joints using 100 m thick palladium filler foil brazed at 1580 and 1610 oC for 600 s, respectively. The application of palladium filler foil shows potential in brazing molybdenum for high-temperature application.

Failure modes of swept spot friction welds in lap-shear specimens of alclad 2024-T3 aluminum sheets are first investigated based on experimental observations. Optical and scanning electron micrographs of the welds before and after failure under quasi-static and cyclic loading conditions are examined. Experimental results show that the failure modes of the welds under quasi-static and cyclic loading conditions are quite different. Failure modes of swept spot friction welds depend considerably on the weld geometry, microstructure, and load amplitude. A fatigue crack growth model based on the paths of the dominant kinked fatigue cracks is developed to estimate the fatigue lives of the spot friction welds. The global and local stress intensity factors for finite kinked cracks, the stress intensity factors for finite transverse cracks, and the Paris law for fatigue crack propagation are used. The fatigue life estimations agree well with the experimental results.

Through the field test of Mayanpo slope at Xiangjiaba Hydropower Station, external deformation, deep deformation, groundwater level and stability of the slope with weak interlayer are analyzed in this paper. The results show that: ① displacement deformation increases with time and decreases with increasing depth. Changes of displacement can be divided into three stages: deformation rapidly increases in the early, and slowly increases in the medium, and becomes gradually stable in the later. Changing rate of displacement decreases with time, and the rate can also be divided into three stages, basically consistent with the displacement changing stage; ② a certain thickness of weak interlayer and evident dislocation exists in slope strata. Dislocation rate first increases and then decreases until basically stable, and local fluctuation is mainly affected by rainfall and dynamic equilibrium adjustment of the slope internal deformation; ③based on the penalty function contact of pile soil and the surface of rock mass, the three-dimensional numerical model of coupling of seepage and strain has been established, and through analyzing and comparing with field test data, it is verified that the model is feasible in the study on slope deformation; ④ through stability analysis of Mayanpo slope by strength reduction FEM, stability coefficient is 1.72.

A novel approach of brazing porous W and Mo using three clad Ti-Ni-Nb foils has been performed in the experiment. Clad Ti-Ni-Nb filler foils are featured with low brazing temperature of below 1350°C. Both W and Mo are completely soluble with β-Ti and Nb, and the Ni addition into the braze alloy is served as a melting point depressant (MPD). Decreased brazing temperature and/or time are necessary in order to minimize infiltration of the molten braze into the porous W substrate. According to the experimental results, Ti-Ni-Nb ternary alloys are promising filler metals in low-temperature brazing porous W and Mo.

To address the mainstream technology of UV-LIGA combined with micro-electroforming which could only fabricate micro-moulds cavity with vertical wall structure and low depth-to-width ratio, a new forming process based on femtosecond laser combined with laminated slip-welding was proposed in the paper. The forming process was achieved through experiment and it proved that the forming process could be a useful method for the process of micro-moulds with high depth-to-width ratio and complex structures. Work-pieces which were 0Cr18Ni9 stainless steel foils whose thickness was 20μm were welded by resistance welding machine and the microstructure of welding-zone was observed in detail. It was found that the welding-zone was composed of nugget zone, fusion zone and heat affected zone. Through the study of welding mechanism, the cooling rate of nugget zone was 3.99×104K/s and there was dynamic recrystallization in nugget zone. For further study, through the X-ray diffraction (XRD) test, it was found there were no chromium carbide and iron-copper eutectic alloy in nugget zone.

An on-site test on envelope of a typical steel residential building in cold region is performed. The testing results provide evaluation bases for the energy-saving effects of the steel residential building. In order to evaluate the main factors that influence energy dissipation of the building and estimate the main energy dissipation positions, the heat transfer coefficient K of envelope and its actual energy consumption are calculated based on the testing data. The results indicate that the building envelope has good heat storage property and it could keep indoor thermal stability; the steel frames and windows have heat bridge effects. Through calculations of the energy consumption of envelope, it is showed that the tested building only meet the requirement of energy saving by 50%, instead of 65%; the external walls and windows are main energy dissipation parts. Finally the thermal design recommendations about steel residential buildings are proposed.

In order to study the sludge microstructure and dewatering performance, the sludge was treated using different conditioners, the same conditioner in a different dosage, the same formula in a different proportion and different order of adding conditioners. The microstructure of dehydrated sludge was observed by scanning electron microscopy. The relationship between the sludge dewatering properties and microstructure characteristics was discussed. It was proven that the different dehydration performance correspond to the different morphology. The better dewatering performance shows more pore at the surface of sludge cake.Contractly, the sludge cake with poor dewatering perform a dense surface, even membranous. Therefore, there is a certain of relationship between the microstructure of sludge cake and its dehydration performance.

The study on tension behavior of casing and dowel joint of square steel tube was carried out by using finite element analysis software ANSYS/LS-DYNA with consideration of geometric nonlinearity, material nonlinearity and contact nonlinearity. On this basis, the effects of inside tube wall thickness, main tube wall thickness, and inserting depth on failure mode, ultimate tensile load and deformation of casing and dowel joint of square steel tube was discussed. The results show that there are three types of failure modes, i.e., bolt failure, inside tube failure and main tube failure, when the joints are subjected to axial tension force. Compare to the joint with the same wall thickness of inside tube and main tube, the reduction of wall thickness of inside tube or main tube will weaken greatly the ultimate tensile load of the joint. The ultimate tensile load of casing and dowel joints is proportional to bolt shear strength, tube wall thickness, inserting depth, and tube edge length. The fruits are useful to the design and application of casing and dowel joints of square steel tube.

The experimental studies were conducted to study the plastic thermoforming heating process. The heaters performance has been evaluated from two different ways: heating water calorimeter for heating efficiency and heating plastics for thermoform processes. The studies of the heaters include gas-fired heater and electric heater. Transient heating processes of plastics were also studied to investigate the heater’s performance on plastics. The surface temperature of plastic at the end of heating process was measured by IR camera. The heating cycle time, surface temperature uniformity of plastic and energy consumed for the heating cycle by different heaters were discussed. The pros and cons of different heaters for plastic heating process were also discussed in this paper.