Preparation and Properties of Bilayer Composite Materials of Cu-coated Fe and CuSn10

Bilayer composite materials of Cu-coated Fe and CuSn10 containing 0%,5%,10%,15%,20%,25%,30%,35%,40%,45%,50%Cu-coated Fe were prepared in mesh belt sintering furnace.Microscopic pore morphology of materials was observed,bending strength was tested.Results show that,There is a good bonding between Cu-coated Fe and CuSn10,with the increase of Cu-coated Fe content from 0%to 50%,bending strength of bilayer composite materials increases.

Maximal and total skew information for a two-qubit system using nonlinear interaction models

Maximal and total skew information is studied. For symmetric pure states of two-qubit, they are closely related to the linear entropy, the concurrence, and the spin squeezing parameter. For a two-qubit system implemented in three nonlinear interaction models with an external field, we give the exact state vectors and the expectation value （Sz） at any time t. Based on （Sz）2, we give the maximal and the total skew information and a condition in which the maximal and the total skew information can reach 1 and 2, respectively.

Tribological Behaviours of PTFE Composites Filled with PEEK and Nano-ZrO2 Based on Pin-on-Flat Reciprocating Friction Model

Nano-ZrO2 and PEEK particles were synergistically filled in unfilled PTFE to improve the wear resistance and maintain a relatively low friction coefficient,and the materials were studied using a reciprocating sliding friction and wear tester.In the friction tests,the evolution of various tribological characteristics in both the contact interfaces and debris was observed,and the wear mechanism of the PTFE composites was investigated.The results showed that the wear rate of the PTFE composites synergistically filled with nano-ZrO2 and PEEK was lower and its friction coefficient was slightly higher than that of the unfilled PTFE;the uniformity and continuity of the transfer film generated by the composite with nano-ZrO2 and PEEK were the best,and the particle size of the debris was minimal in comparison to that in other sample systems.

Maximal and total skew information of three-qubit system obtained using nonlinear interaction models

Both the maximal and the total skew information have been studied. For a three-qubit system implemented in three nonlinear interaction models, we give the exact state vector at any time t. Beused on this, we give the maximal and the total skew information. It is found that they have the same form and their evolution periods are dependent on the energy difference between the ground state and the second excited state in these models. The maximal skew information is always in the （Sx, Sv） plane. We give the condition for the occurrence of IGHZ}sy, in which they can reach the extreme values of 9/4 and 15/4, respectively. In three different decoherence channels, two kinds of information and the concurrence are calculated. We find that the phenomenon of the concurrence of sudden death occurs, but the above two kinds of information do not die suddenly. In the phase-damping channel, the two kinds of information will not be lost completely.

Current Development Situations of Ziziphus Jujuba Industry in South Xinjiang and Recommendations

Through surveying current development situations and existing problems of planting and processing of Ziziphus jujuba in south Xinjiang,this paper discussed planting,processing mode of Ziziphus Jujuba in south Xinjiang and development direction of enterprises in Ziziphus Jujuba production. It is expected to ensure and increase quality and sales volume of Ziziphus Jujuba and promote sound and sustainable development of Ziziphus Jujuba industrial chain in south Xinjiang.

Study on the Logistics Operation of Scale Farm Methane Engineering

Based on the large-scale farms methane project of logistics operation as the breakthrough point, methane project of the supply chain of the raw material supply logistics, production logistics and product sales organization of logistics and operation mode were preliminarily studied, and the methane energy company as the core was decided. The third party logistics as key support for the integration of logistics operation mode provid- ed a new train of thought for the large scale operation and implementation of methane project.

Theoretical and experimental study on shear lag effect of partially cable-stayed bridge

In order to resolve the traffic congestion problem, many cable-stayed bridges are designed with a large width to span ratio. This results in significant shear lag effect to cause nonuniform stress distribution along the flanges of the beam of bridge. This paper reports study on the shear lag effect of the Lanzhou Xiaoxihu Yellow River Bridge. A 3D finite element model of the bridge was developed and finite element analysis (FEA) was done to obtain the theoretical results. To evaluate the theoretical results, a scaled model was made to conduct static test in laboratory. The experiment results accorded with the results obtained by FEA. It is proved that FEA is an effective method to predict shear lag effect of bridges of this type.

Design and Test of the Semi-Automatic Test-Bed with Inclined Belt of Garlic Transplanting Machine

In order to verify the feasibility of semi-automatic garlic planter with inclined belt program and determine its reasonable operating parameters, the semi-automatic test-bed with inclined belt of garlic transplanting machine was designed, and the garlic box experiments were conducted. The angle of inclined belt on the test-bed and its running speed were adjustable. Single factor test results showed that the program of the semi-automatic garlic planter with inclined belt was feasible, and the angle of inclined belt and the test bed running speed affected the indicators. Orthogonal experiment results showed that the angle of inclined belt was the main factor affecting the test indicators. It is also found that the best angle was 30 degrees, while the most reasonable running speed was 0.75 Km/h.

Waveband Selection with Equivalent Prediction Performance for FTIR/ATR Spectroscopic Analysis of COD in Sugar Refinery Waste Water

The level of chemical oxygen demand(COD)is an important index to evaluate whether sewage meets the discharge requirements,so corresponding tests should be carried out before discharge.Fourier transform infrared spectroscopy(FTIR)and attenuated total reflectance(ATR)can detect COD in sewage effectively,which has advantages over conventional chemical analysis methods.And the selection of characteristic bands was one of the key links in the application of FTIR/ATR spectroscopy.In this work,based on the moving window partial least-squares(MWPLS)regression to select a characteristic wavelength,a method of equivalent wavelength selection was proposed combining with paired t-test equivalent concept.The results showed that the prediction effect of the selected wavelength was very close to that of the MWPLS method,while the number of wavelength points was much smaller.SEPAve,RP,Ave,SEPStd,and RP,Std which characterized the modeling effect were 26.3 mg L^-1,0.969,3.49 mg L^-1,and 0.006,respectively.The validation effect V-SEP and V-RP were 28.64 mg L^-1 and 0.960,respectively.The selected waveband was between 1809 cm^-1 and 1568 cm^-1.The method was of more reference value for the design of FTIR/ATR spectral instrument for COD detection.

Band Selection Method of Absorption Peak Perturbance for the FTIR/ATR SpectrumAnalysis

The rapid quantification method of human serum glucose was established by using the Fourier transform infrared spectroscopy(FTIR)and attenuated total reflection(ATR).By the subtracted spectra between glucose aqueous solution and de-ionized water,absorption peaks are calculated in fingerprint area.Based on these absorption peaks and multiple linear regression(MLR)model,discrete band selection method of absorption peaks disturbance model(APDM)was developed.5 absorption peaks 1150 cm^-1,1103 cm^-1,1078 cm^-1,1034 cm^-1,991 cm^-1 were found in fingerprint area.Used these absorption peaks to establish absorption peaks disturbance model,the optimal wavelength combinations are 1140 cm^-1,1096 cm^-1,1084 cm^-1,1030 cm^-1,993 cm^-1,the corresponding C-RMSEP and C-RP are 1.164 mmol/L and 0.828 respectively.The results show that the optimal prediction effect of APDM was obviously better than the one of the Partial least squares(PLS)model,and the complexity of the optimal model is reduced greatly also.The results also provide a theoretical basis for design of small and portable human serum glucose spectrometer.

Wetting behavior and reaction mechanism of non-corrosive flux on aluminum

The energy-dispersive spectroscopy （ EDS ） , X-ray diffraction analysis （ XRD ） and differential thermal analysis （DTA） were used to analyze the melting, spreading process, and reaction mechanism of non-corrosive flux on the surface of aluminum. The result indicates that the whole process can be divided into three stages. In the first stage, flux is heated from room temperature to its melting point, which is called the endothermic stage, mainly absorbs heat and generates a small amount of liquid flux. When the temperature exceeds the melting point of flux, a large amount of liquid flux is generated and reacts with oxide films on the surface of aluminum. This stage is called the reaction stage. The third stage is a spreading and cleaning process, in which residues and reaction products quickly flow out from the center with liquid flux. The different compositions of flux perform different functions in brazing. K3AlF6 can remove oxide film us a cleaner. Only in liquid or molten state can flux remove oxide film on the substrate.

Study on Wheel and Workpiece Position Error Influence on Surface Shape Accuracy during Ceramic Ball Grinding

The reasons for bringing surface accuracy error in ultra-precision grinding ceramic ball joint were analyzed,and the influences wheel position error and shaft run-out error on the ball joint surface accuracy were discussed.Through establishing three-dimensional grinding model,the mathematical relationship between the position error and surface accuracy was derived,and the distance from any point on spherical surface to the ideal center was calculated when position error existed,and a precise surface shape was got,and theoretical support was provided to improve the surface accuracy during the grinding process.Using self-developed ultraprecision grinding machine to do the ceramic ball grinding experiment,the surface accuracy PV value of ceramic spherical joint is 4.8μm.

Experimental study on the sampling efficiency of the whirl type separation sand sampler in a wind tunnel

A performance test was conducted in a wind tunnel by changing the principal configuration parameters of a sampler such as the diameter of the container, inlet width and cone height. The results show that the average sand collection rate is from 80% to 90% when any one of the configuration parameter levels is changed. However, the variation of a parameter level results in different ef-fects on the sand collection rate for each soil sample within a certain size range of sand grains. The results show that for various sand grain sized soil sample at each wind speed, the sand collection rate decreases when the diameter of the container changes from 50 mm to 40 mm, the sand collection rate increases by about 2%-3% when the inlet width changes from 10 mm to 8 mm, and the sand collection rate increases by about 3%-4% when cone height is altered from 100 mm to 125 mm. The average sand collection rate is enhanced by 2%-4% for the soil sample of different sized sand grains when the diameter of the container is 50 mm, the inlet width is 8 mm, and cone height is 125 mm.

Moisture Content and Nutrient Composition of Alfalfa under Different Drying Methods

[Objective] The paper was to study the effects of different drying methods on moisture content and nutrient composition of alfalfa.[Method] Alfalfa collected from the same piece of land in early flowering period were dried through three different drying methods, solar drying,outdoor drying in the sun and outdoor drying in the shade, and the effects of different drying methods on contents of moisture, crude protein, crude ash and neutral detergent fiber（NDF） were measured. [Result] The moisture evaporation rate of different drying methods over the same period successively were solar drying 〉 outdoor drying in the sun 〉 outdoor drying in the shade. The crude protein content of alfalfa was the highest through solar drying（P〈0.05）, followed by outdoor drying in the shade, and the crude protein content through outdoor drying in the sun was the lowest. Under the condition of different moisture contents, the crude protein content of dried samples through outdoor drying in the sun decreased by 6.86%-22.43% compared to solar drying, and that through outdoor drying in the shade reduced by 4.92%-17.20%. Under the same moisture content, the crude ash content successively were outdoor drying in the shade 〉 outdoor drying in the sun 〉 solar drying; the crude ash content of alfalfa through solar drying was 3.72%-19.22% lower than outdoor drying in the sun, and 8.12%-29.93% lower than outdoor drying in the shade. The NDF content of alfalfa through outdoor drying in the sun was the highest, significantly higher than the other two drying methods（ P〈0.05）. The NDF content through solar drying was the lowest, 9.08%-27.25% lower than outdoor drying in the sun, and 4.84%-24.84% lower than outdoor drying in the shade. [Conclusion] The paper will provide some references for selection of appropriate alfalfa drying method.

Enhanced efficiency of the Sb_(2)Se_(3)thin-film solar cell by the anode passivation using an organic small molecular of TCTA

Antimony selenide(Sb_(2)Se_(3))is an emerging solar cell material.Here,we demonstrate that an organic small molecule of 4,4',4''-tris(carbazol-9-yl)-triphenylamine(TCTA)can efficiently passivate the anode interface of the Sb_(2)Se_(3)solar cell.We fabricated the device by the vacuum thermal evaporation,and took ITO/TCTA(3.0 nm)/Sb_(2)Se_(3)(50 nm)/C60(5.0 nm)/Alq3(3.0 nm)/Al as the device architecture,where Alq3 is the tris(8-hydroxyquinolinato)aluminum.By introducing a TCTA layer,the open-circuit voltage is raised from 0.36 to 0.42 V,and the power conversion efficiency is significantly improved from 3.2%to 4.3%.The TCTA layer not only inhibits the chemical reaction between the ITO and Sb_(2)Se_(3)during the annealing process but it also blocks the electron diffusion from Sb_(2)Se_(3)to ITO anode.The enhanced performance is mainly attributed to the suppression of the charge recombination at the anode interface.

Oscillation Reduction of Breast for Cup-Pad Choice

Traditional studies of evaluating breast displacement included cup fabrics,shoulder straps,and under-bands restricted by own features of sports bras(SBs).The effects of pads on breast support during movement were investigated by conducting trials with the motion capture experiment.The three-dimensional breast displacements at five breast positions were collected and values in the vertical direction were evaluated.Results indicate that the effectiveness of the cup pad depends on the pad diameter and the thickness.SBs with larger pads and thicker pads made of soft polyurethane cause less overall breast displacement during vertical jumping compared to unpadded bras(p<0.05).The effectiveness of bra oscillation reduction was characterized by the total reduced percentage of the breast displacement.These findings enlarge scopes in terms of the current breast displacement analysis and understanding of selecting SBs associated with changes in the specifications of pads,thereby providing objective methods for bra cup evaluation and a design basis for breast protection.

Potato seed-metering monitoring and improved miss-seeding catching-up compensation control system using spatial capacitance sensor

The congenital yield reduction caused by miss-seeding in spoon-type seed-metering device of small and medium-sized potato planter is huge.Based on the physical mechanism of different measured capacitance values between two fixed capacitor plates with different media,a miss-seeding detection scheme based on a spatial capacitance sensor is proposed first.A simple and efficient spatial capacitance sensor that can obtain as large capacitance measurement value as possible is designed,and a dual CPU coordinated seed-monitoring and compensation control system architecture is adopted.AD7745 is selected for the capacitance measure of the spatial capacitance sensor,and the code of grating encoder is also recorded at the same time.Thereby,when each potato spoon passing through the space surrounded by the capacitor plates,the maximum net capacitance fluctuation and its corresponding position can be acquired.A suitable threshold can distinguish between normal-seeding and miss-seeding effectively.Moreover,it should be emphasized that,this monitoring system only requires one monitoring point.Then,based on obtained information,an improved miss-seeding catching-up compensation plan is put forward.By utilizing the powerful memory capability of the CPU,this system does not need to complete compensation immediately after the miss-seeding identification.Instead,the miss-seeding information and the location of the accident can be just marked in advance,and only when the opportunity arrives,can the miss-seeding catching-up compensation be truly executed.In this way,the position of the seed-monitoring points can be free from restriction,and the control strategy can therefore be significantly simplified.The soil tank test data showed that,the identification accuracy of the miss-seeding detection system was not less than 94%.When the seed-metering chain speeds are 0.2,0.3,and 0.4 m/s,the average success rates of the miss-seeding compensation system are 94.32%,83.65%,and 75.00%,respectively.The final miss-seeding rate can be below 3%,and the average deviation compensation rate was not higher than 30%,the miss-seeding was suppressed significantly.This system is a beneficial try in the non-photoelectric detection field and low complexity miss-seeding compensation for potato seeding.

Corrosion resistances of metallic materials in environments containing chloride ions:A review

Corrosion,more specifically,pitting corrosion happening extremely in marine environments,leads to lifespan of materials drastically decreasing in service,which causes enormous economic loss and even environmental disaster and casualties.In the past decade,increasing efforts have been made to study the corrosion behaviors of materials in chloride-containing aqueous environments.Herein,this work provides an overview of recent progress in understanding the degradation mechanism and improving the corrosion resistance and corrosion-wear resistance of materials from bulk metal to surface treatment involving organic coating,metal and its alloy or compound coating.The particular emphasis is given to the periodic layered structures(PLSs),whose anti-corrosion properties outperformed others to some extent,wherever in terms of bulk metal or surface treatment,regardless of aggressive environment(corrosion or corrosion-wear conditions).Numerical simulation based on kinds of models at different scales is introduced to deeply understand the process of corrosion and/or corrosion-wear in chloride-containing aqueous environment.Combined experimental result with numerical simulation,the micro-galvanic corrosion dominated degradation mechanism of PLSs is critically analyzed.Types of setups to realize corrosion-wear in laboratory are also summarized.At last,future research and development are prospected,offering to develop a basic application of PLSs designed by corrosion protection methodology in the near future.

Study on Immobilized Lipase Catalyzed Transesterification Reaction of Tung Oil

The transesterification reaction conditions of tung oil with methanol have been studied in this article, with immobilized lipase NOVO435 as catalyst. The response surface methodology was used to optimize the transesterification reaction of tung oil in a nonsolvent system. The optimal conditions were rotation rate 200 r/min, molar ratio of methanol to oil 2.2： l, reaction temperature 43℃, and the catalyst amount 14% （based on the weight of oil）. After reacting for 18 h, 67.5% of the oil was converted to its corresponding methyl esters （the theoretical ester conversion was 73.3%）. The lipase was washed by organic solvents after each reaction and was reused again. The esters conversion of tung oil was decreased by 6% after the lipase was reused for 120 h. The theoretical amount of methanol was added in two steps, 85% ester conversion was obtained after 36 h of reaction （theoretical ester conversion was 100%）. The molar ratio of methanol to oil, the catalyst amount, the reaction temperature, and reaction time were all highly significant factors, and there was a relative significant interaction between every two factors.