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Background. Type 2 diabetes mellitus (T2DM) is one of the most common chronic diseases in adults, causing high morbidity and mortality worldwide. In recent years, the prevalence of T2DM has been increasing significantly, and genome-wide association studies (GWAS) have shown that KCNQ1 significantly increases the risk of T2DM. Objective. To find large-scale evidence on whether the KCNQ1rs2237892C⟶T gene polymorphism is associated with T2DM susceptibility. Methods. A comprehensive review of the Chinese and English literature on the association of T2DM with KCNQ1rs2237892 is published by PubMed and Baidu Academic. The included literature was part or all of the studied loci which were evaluated for association with T2DM. Forest plots were made of the included literature to analyze the association of KCNQ1 with polymorphisms of the studied loci, and funnel plots and Egger’s test were used to evaluate the publication bias of the selected included literature. Results. Ten case-control studies including a total of 7027 cases and 8208 controls met our inclusion criteria. Allele (C allele frequency distribution) (OR: 1.19; 95% CI: 0.87,1.62; P < 0.00001 ), recessive (OR: 0.73; 95% CI: 0.45,1.18; P < 0.00001 ) genetic model under the full population was observed between KCNQ1rs2237892C⟶T gene polymorphism and T2DM without a significant relationship. In a stratified analysis by race, a meaningful association was found in non-Asian populations under the allelic genetic model, but no association was found in Asian populations. Conclusion. This meta-analysis showed no significant association between the rs2237892 polymorphism of the KCNQ1 gene and the risk of T2DM.

In this work, tungsten thin films were deposited on different substrates by magnetron sputtering and some of the films were then annealed at 1000°C for 1 hour in order to investigate the influence of different processing parameters on morphology and microstructure of films. Scanning electron microscope and x-ray diffraction were used to detect the morphology and microstructure of films. Under the same conditions, the thin films on different substrates showed different preferred grain orientations although the morphologies were similar. After thermal treatment, the morphology of films changed significantly and the total stress parallel to film surfaces dropped off sharply.

The paper adopts modified carbon fiber with Meldrum's acid and silane coupling agent (KH-550), then add the modified carbon fiber to the paper based friction materials. The paper aims to explore the changes of modified carbon fiber in its surface structure and properties by electron microscopy and infrared spectral analysis, and the effect of anionic microparticle forming retention aid system comprised of lithium soapstone-cationic polyacrylamide (CPAM) on mechanical properties and retention of paper based friction materials. Compared with the addition of unmodified carbon fiber to paper based friction materials, the addition of modified carbon fiber with Meldrum's acid, silane coupling agent, Meldrum's acid and silane coupling agent enhance the tensile strength of paper based friction materials. The tensile index of paper based friction materials was separately enhanced by 64.87 %, 91.38 % and 28.88 %. Compared with the paper based friction materials without the anionic microparticle forming retention aid system, the basis weight of paper based friction materials increased by 13.97 %.

By changing ther factors of synthesis process of PAE, discussed the effects of synthetic conditions on the PAE curing, and through electron microscope analysis methods, the curing mechanism of PAE is preliminary discussed.When the ratio of DTEA/AA was 1:1.05,the dry and wet strength of paper before and after curing achieved the best value.when the dosage of p-toluene sulfonic acid is 1.5%, the PAE can achieve best effect.the best ratio of PPC and epichlorohydrin is 1:0.7.

This paper mainly discuss the effect of beating on OCC pulp fiber morphology and paper physical Strength. After the treatment with PFI, the beating degree were ranged from 25 ° SR rises from 56 °SR, the fiber morphologies were greatly changed, and appeared splitting and brooming. Physical results showed that beating can improve strength properties of OCC pulp in the proper degree, 46°SR was the best result in this study.

Hydraulic press occur elastic deformations in the working status. The deformation will affect the precision of the products. This paper expounds the method of using Laser tracker test rigidity of THP11-10000A isothermal forging hydraulic press. And we test the deformation of the lower bean, fit the date and compare with fitting of the finite element simulation results. The validity and the accuracy of the simulation results are verified.

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.

A kind of refractory fiber cardboard functioning as building insulation materials was developed. To improve the cardboard abilities to bear high temperature, sepiolite and alumino-silicate fibers were chosen as the raw materials for making refractory fiber carboard. In addition, inorganic adhesives and PVA fiber were used as bonding agents to enhance the physical strength of cardboard. The effect of bonding agents amount on tensile strength of the cardboard were investigated. When choosing inorganic adhesives and PVA fibers as the adhesives, the optimum condition is that amount of aluminum sol and PVA fibers is 30%and 3%-4% by weight, respectively; The best technical conditions for making the refractory fiber cardboard were determined. When the mass ratio of alumino-silicate fibers, sepiolite fiber, PVA fibers is 90: 6: 4, the physical strength of refractory fiber cardboard can be up to 1.556N·m/g. When the bulk density of the cardboard is 305.8kg/m3, the thermal conductivity of insulation cardboard at 200°C is very low, which is only 0.065W/m·K.

In this thesis, the process of electromagnetic drying cylinder was analyzed creating by the dryer finite element model using ANSYS. The conduction thermal analysis, the applied load and solved showed the results of three major components. Which create a finite element model of the process, mainly the preprocessor using ANSYS software to create or import geometric models from other software applications, and then add the material properties. The last of the geometric model meshing and solving process need to enter solvers according to the actual situation. The setting is applied to the thermal load and conditions. Then it is proceed to the finite element solution operator. It final usually the Post 1, or Post2 view results, and based on our experience to judge correctly

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.