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An optical scheme using two correlationless beams to suppress the speckle of the pico-projection system is proposed. By using two broadband beam splitters (BBS) and two high reflection mirrors, the originally incident laser beam is split into two beams. The mutual correlation coefficient between two split beams is very close to zero. We use the haze reflection based on the random scattering model to simulate light reflected from the rough surface. In simulations, light is respectively reflected from the same size flat and rough surfaces and both recorded images are compared with each other. The image from flat surface is very clear on the detector plane. On the contrary, the image from rough surface is very fuzzy and the edge is hard to figure out. The simulations show that the speckle contrast ratio (CR) is reduced from 1.0 to 0.707. We find out a solution of the speckleCRless than 0.71 when the distance between two BBSs is 2.4 mm and the thickness of each BBS is 0.4 mm. Finally, we carry out an experiment and verify the simulating results. By our analysis from the experimental data, the speckleCRcan be reduced about 25% which is close to the theoretical value of 29.3%.

A program based on the SOR method have been setup for calculating the electrostatic potential inside the electron optical system (EOS). This method can deal with large domain calculation more efficiently than by using the finite difference or finite element methods. Since the MEBDW system is composed of an array of EOSs, periodic boundary conditions in thexandydirections are applied. A case of EOS is demonstrated in this paper.

The variable tension control system of strip winding is a nonlinear, strong coupling and time-varying system. Traditional fuzzy controller with fixed control rules cannot obtain the desired control performance of the strip winding system. So the fuzzy control algorithm with adjustable factorαis proposed, and the introduction of adjustable factors can change the fuzzy control rules. The tension fuzzy controller with adjustable factorαis designed, and simulation model of the system is established using Matlab software. The result of simulation shows that tension fluctuation of the tension fuzzy control system with adjustable factor get small, comparing the tension fuzzy control system with adjustable factors with the ordinary tension fuzzy control system. The tension fuzzy control system with adjustable factors has fast system response and strong anti-interference ability.

In this experiment, we use corn starch as the main raw material and use Mid-Temperature a-amylase to modifie it. The influnce of temperature and time to viscosity of the enzymatic starch were discussed. In this way, we can get the optimal conditions about enzymatic modification. According to testing properties of the paper ,we know about its surface sizing effect. At last,we explored the influnce of AKD to surface sizing. The results showed that the optimal conditions are as follows: the optimal enzyme reaction temperature of 65 °C and the ptimal enzyme reaction time of 20min under the condition that the substrate concentration of 20%, the dosage of enzyme of 0.02%, the dosage of calcium chloride of 0.04%, pH 6, gelatinization temperature of 95 °C, and gelatinization concentration of 10%.Under this condition, the viscosity of starch paste is 11mPas. Compared with original paper, sizing increased by 16.20%, burst index increased by 10.50%, tensile index increased by 12.60%. The AKD can significantly improve the degree of sizing, compared with the original paper, the degree of sizing increased by 26.5%.

Based on the domestic OCC pulp as raw material, it was found that the optimum conditions for laccase treatment were: the concentration of laccase 16U/g dry pulp, the pulp consistency 5%, temperature 50 °C, pH=5.0 and reaction time 90min. OCC treated with laccase alone can improve paper strength properties. The dry tensile index and wet tensile index of the control sample were 21.80 Nm/g and 0.22 Nm/g, respectively. The dry tensile index and wet tensile index after OCC treated with laccase alone were 23.36 Nm/g and 0.28 Nm /g. Comparing to the control pulp, the dry tensile index and wet tensile index of OCC treated with laccase were increased by 6.88% and 27.3%, respectively. At the same time, the laccase system can obviously improve the strength of the pulp properties with adding the mediator, especially using histidine, the dry and wet strength of paper was largely improved.

In this study, we prepared unbleached chemi-mechanical pulp from waste poplar wood using alkaline processing under normal atmospheric pressure. The influnce of alkaline dosage and time to fiber morphology and properties of the paper were discussed. The parameters of fiber including the length ,width and curl index were measured by FQA. The optimal dosage of NaOH and the optimal time of soaking period in the preparation of pulp using waste poplar wood were studied. The results showed that the optimal dosage of NaOH was 6% and the time of soaking period was one day. The performance of the handsheet made from the poplar wood under the pulping conditions are as follows: tensile strength index of 27 N·m/g, tear index of 0.51 mN·m2/g, burst index of 1.7 KPa·m2/g, folding strength of 16 times, ring crush strength index of 5.7 N.m/g, whiteness of 55.5 ISO, white opacity of 97%, paper absorption liquid rate of 0.32 mm/s.

With the development of world's paper industry, strength agent has become increasingly wide spread and more important.This paper describes a method for modified APMP with Chitosan, we make studies on using chitson to improve the properties of paper, and compare the effect of them based on experimential results. As a result of study,it can be concluded: The pH value and the dosage of chitosan have a great influence on the physical strength of paper.When the pH was 6 and the dosage of chitosan was 1%,the tensile index of paper could reach 30% above.

By the preceding experiments, we concluded that the optimum conditions for laccase treatment were: the concentration of laccase 16U/g dry pulp, the pulp consistency 5%, temperature 50 °C, pH=5.0 and reaction time 90min. We studied the change of water retention value and carboxyl content changes under the best conditions. As well as we studied the effect of pulp strength properties by biological treatment combined with mechanical treatment. Moreover, environmental scanning microscope images showed that more collapse and more fibrillation were observed on the beating combined with laccasehistidine-treated fiber surface than the control samples, which led to form better bonding between fibers in handsheets resulting in the increase of the paper strength of beating combined with laccasehistidine-treated OCC pulp.

initiator is one of the most important conditions of synthesizing efficient strength agent CPAM. To begin with initiating mechanism, three redox systems of acrylamide aqueous polymerization (NH4)2S2O8/ Na2 SO3, K2S2O8/NaHSO3 and K2S2O8/Na2 S2O4 have been studied. The effects of different kinds of initiator, initiator concentration, and monomer concentration as well as polymerization temperature on relative molecular weight and strength effects of CPAM have been investigated. K2S2O8/Na2 SO3 is the most useful system in synthesizing efficient strength agents.

The paper has learned on the preparation of nanometer carbon black and polypropylene nanocarbon black-polypropylene composite material by using the small extrusion blending mixer which has been designed by our team. The results show that: Resistance of nanometer carbon black - polypropylene composites decreases with increasing carbon black content and extrusion mixing times. Through single factor experiment and orthogonal experiment to determine the optimum process conditions are at 260°C, nanocarbon black content 60%, extrusion mixing times 5. Under these conditions the resistance of nanometer carbon black-get polypropylene composites is 12.73 ohms.

The research of conductive polymer material has received the widespread attention and development. This article has introduced the classification and preparation methods of conductive polymer materials, conductive mechanism, application and research progress in various fields.

A photonic crystal waveguide coupled structure can be constructed by putting three photonic crystal waveguides in parallel and adjacent form. Study the coupling of the approximate solution interference acts and the self-image phenomenon of this multi-mode waveguide system based on the guided mode propagation analysis method, a three-channels multimode interference wavelength division multiplexing is designed. The presented device not only has a high transmission rate, but also has the advantages of multiple wavelength selection and may have potential and practical applications in the field of photonic integrated circuits in future.

The aims of prehydrolysis are mainly removing pentose and decreasing viscosity in the preparation process of dissolving pulp. In this paper, the effect of prehydrolysis in the preparation process of poplar and bamboo dissolving pulp were investigated under different prehydrolysis conditions. The optimum prehydrolysis process conditions of poplar were obtained as followings: the liquid ratio of 1:6, the highest temperature of 160±2°C, heating time of 90min, holding time of 120min, H2SO4 of 1.0%, the P-factor was 1537. Under this condition, the results showed that the content of pentosan decreased from 24.10% to 7.85%. The optimum prehydrolysis process conditions of bamboo were obtained as followings: the liquid ratio of 1:8, the highest temperature of 160±2°C, heating time of 90min, holding time of 120min, H2SO4 of 1.0%, the P-factor was 1549.And the content of pentosan was also decreased from 19.64% to 6.76% by the prehydrolysis process.

In this study, the high density 900kg/m3 biodegradable cellulose fiber composites have been successfully manufacture from treated cellulose fiber by wet-hot pressure technology. The cellulose fiber was treated with cationic guar gum(CGG) by the process of adsorption. It was found that the composite made from treated cellulose fibers have better mechanical properties such as the tensile properties and stiffness. Chemical groups of samples were studied through the use of FTIR spectroscopy.

Sepiolite has good adsorptivity due to their high surface area and structural channels. During the process of making aluminium silicate fiber paper, inorganic binders retaintion was little because of the smooth surface of aluminium silicate fibers. In this study, sepiolite was used to improve tensile strength of the sheet by increasing inorganic binders retaintion rate through its high adsorptivity. The effect of sepiolite on the tensile strength of alimunium silicate fiber paper was investigated. The results showed that the best mass ratio of aluminium silicate fibers to spiolite was 7:3. Under this condition, the tensile strength of the sheet was 4.79 N•m/g, which increased by 24.2% from the one without sepiolite.

In this paper, we proposed the method to synthesize the modified polyamide polyamine enhancer, which takes PAE, styrene and acrylic as raw materials. Factors that would affect the preparation of the modified polyamide polyamine enhancer, such as monomer amount, reaction time, initiator amount and emulsion concentration, were discussed in detail. Experimental results showed that the modified polyamide polyamine enhancer achieved optimum effect the strength of tube roll base paper under the conditions: the amount of acrylic is 6%, the ratio of styrene and PAE is 2:1, holding time 4h, and the amount of initiator 0.7%. The modified polyamide polyamine enhancer applied to tube roll base paper. The optimum amount of modified polyamide enhancer was 1%. The ring crush strength of paper prepared in this condition can be increased by 44% and the stiffness can be increased by 46%.

PAE as the wet strength agent has a long history; it not only has the wet strength performance and the retention and drainage characteristics. This paper focuses on the technological conditions of preparation of PAE wet-strength agent and the application conditions. The results showed that the well PPC was obtained under the following conditions: the mole ratio of adipic acid and diethylenetriamine were 1:1.05, the amount of catalyst (mole ratio of the total raw materials) was 1%, the temperature of heat preservation was 165°C and the reaction time was 4h. The optimum condition of preparing PAE was obtained as followings: the ratio of EPI to PPC of 1.2:1, the epoxidation temperature of 60°C and reaction time of 2h. While applied in softwood pulp, when the dosage of PAE was 1%, the wet strength agent provided the satisfactory effect.

The nondestructive estimation of key parameters during plant-field chicken manure composting is of great importance for quality evaluation. In the process of developing regression models using near-infrared spectroscopy (NIRS), methods used for wavelength selection significantly influence on the efficiency of the calibration. This study explored the method of genetic algorithms (GAs) for selecting highly related wavelengths to improve NIRS models for moisture (Miost), pH and electronic conductivity (EC), total carbon (TC), total nitrogen (TN) and C/N ratio determination in chicken manure during composting. Based on the values of coefficient of determination in the validation set (R2) and root mean square error of prediction (RMSEP), the prediction results were evaluated as excellent for Miost, TC and TN, good for pH and EC, and approximate for C/N ratio. But GAs had better performance than using full spectrum for near-infrared spectroscopy model construction in the process of evaluating key parameters during plant-field chicken manure composting.

Kinematics model of welding robot is built in the paper. An improved fuzzy controller (Fuzzy-P) for welding robot mobile platform is designed based on analyzing seam tracking control system. The domain of fuzzy control should not be set too big in order to make system smooth, but the system must respond rapidly. P control can respond rapidly. When weld seam deviation is big,it adopts P control while seam deviation is small, it adopts Fuzzy-P control. The simulation result shows that the improved controller is effective for 45°broken line; the welding torch is able to track the welding seam well.

We explored a new type EAM potential (CLI-EAM) that the value of atomic electron density and pair potential functions are obtained by Chen’s lattice inversion based on first-principles calculations. This EAM potential is applied to Cu, Ag, Cu and Pt metals successfully and the results of basic properties agreed with the experiments. For the same metal, the cohesive energy of fcc structures are the lower than bcc structures.

In this thesis, a model of water injector is established, which can prevent water from splashing when high-velocity flow pours into a container. With the periodic boundary, the 1/18 calculation domain model is built. Then two-phase flow numerical simulation research is done on the device with the steady VOF model. The influencing factors of water injector's performance and the variation laws under different working conditions are obtained. The reliability of the results is improved by comparing the results from different calculation methods with that from steady-state VOF method. And through the experimental researches on the splash-proof water injector, the accuracy of the numerical simulation results is validated.

The numerical simulation of the resistance characteristics of the inertial stage had been researched with different turbulence models, and the resistance characteristic computation curves of the inertial stage with different turbulence models have been obtained. Then curves contrasted with the actual value from experiments. The results show that the error of the Standard model is a little larger, but results of the RNG and Reynolds Stress are comparatively accurate. It has provided the reference frame of the turbulence model selection when the numerical simulation of the inertial stage is conducted.

The mesh of the multilayer gauze stage was simplified from the crossing arrangement to the unilateral arrangement, and the simplification from three-dimensional to the two-dimensional came true. The calculation capacity was effectively controlled by means of the periodic boundary. The numerical simulation of the multilayer gauze stage with different layers has been done. After the several calculation with different operating conditions, the resistance characteristic curves of the corresponding models was gave out. The relationship between the layers of the multilayer gauze stage and the resistance characteristic has been worked out. The experiments on resistance specialty of the multilayer gauze stage have been done on the special wind-tunnel. The experiment result was compared with the numerical simulation result, in order to provide the effective information for the further research.

Using such methods as questionnaire survey and experimental study, a study has been made on the effects of yoga on female college students’ body shape, the quality of physical function, mental health and so on. Methods: The study sampled 25 2009 female students in Handan College who have selected the yoga course. These students will do yoga practice for 6 months. The body shape, body function and mental health will be tested before and after the exercise. The results show that: such four indicators as body weight, waist circumference, thigh circumference and upper arm circumference; such 6 indicators as vital capacity, heart rate, VO2, sit-ups, step test, and Sit and Reach and such indicators as mental health self-assessment questionnaire (SCL--90), self-rating anxiety scale (SAS), and self-rating depression scale (SDS) have been improved significantly compared to those before practice. Conclusion: Through yoga practice, female college students can improve their physical health, balance physical and mental condition, and relieve stress, enhancing the quality of physical function and mental health.

A computational modeling and simulation method for multi-posture gymnastics jump based on sport biomechanics was improved. Taking tuck jump, pike jump and arched jump as examples, the entire jump phase was seperated into four parts: taking off from bending the knees, airborne, posturing and landing. Then the formulas were developed for modelling. Finally, computational simulation experiment was done with the formulas. The simulation outcomes showed that this method is effective in multi-posture gymnastics jumps analysis.