Deformation behaviors of 21-6-9 stainless steel tube numerical control bending under different friction conditions

For contact dominated numerical control(NC) bending process of tube, the effect of friction on bending deformation behaviors should be focused on to achieve precision bending forming. A three dimensional(3D) elastic-plastic finite element(FE) model of NC bending process was established under ABAQUS/Explicit platform, and its reliability was validated by the experiment. Then, numerical study on bending deformation behaviors under different frictions between tube and various dies was explored from multiple aspects such as wrinkling, wall thickness change and cross section deformation. The results show that the large friction of wiper die-tube reduces the wrinkling wave ratio η and cross section deformation degree ΔD and increases the wall thinning degree Δt. The large friction of mandrel-tube causes large η, Δt and ΔD, and the onset of wrinkling near clamp die. The large friction of pressure die-tube reduces Δt and ΔD, and the friction on this interface has little effect on η. The large friction of bending die-tube reduces η and ΔD, and the friction on this interface has little effect on Δt. The reasonable friction coefficients on wiper die-tube, mandrel-tube, pressure die-tube and bending die-tube of 21-6-9(0Cr21Ni6Mn9N) stainless steel tube in NC bending are 0.05-0.15, 0.05-0.15, 0.25-0.35 and 0.25-0.35, respectively. The results can provide a guideline for applying the friction conditions to establish the robust bending environment for stable and precise bending deformation of tube bending.

INFLUENCE OF SO_4^(2-) AND Cl-ON THE CORROSION BEHAVIOR OF COPPER TUBE IN AIR-CONDITIONING SYSTEM

The influence of chloride or sulphur dioxide on the corrosion behavior of copper tube in the air-conditioning system was studied using scanning electron microscope (SEM), energy dispersion spectrometer (EDS) and cyclic polarization techniques. The results showed that the corrosion of copper tube are mainly caused by the SO42- and Cl- ions in the circulating water, and the former is mainly responsible for the general corrosion of the copper tube whilst the latter for the pitting corrosion. The different influences of SG42- and Cl- ions on the corrosion type of copper tube may be attributed to that the radius of SO42- ion is much larger than that of Cl- ion. Meanwhile the results also indicated that SO42- inhibits the pitting corrosion caused by Cl- and Cl- inhibits the general corrosion initiated by SO42- due to their competitive adsorption on the copper matrix.

A New Co(Ⅱ) Coordination Polymer Based on a Flexible 1,4-Cyclohexanedicarboxylic Acid: Synthesis, Structure and Thermal Behavior

A new Co（Ⅱ） coordination polymer, [Co（1,4-chdc）（L）（H2O）]n（1）, was synthesized under hydrothermal condition（1,4-H2chdc = 1,4-cyclohexanedicarboxylic acid, L = 2-（4-fluoro-phenyl）-1 H-imidazo[4,5-f][1,10]phenanthroline）. Its crystal structure was determined by single-crystal X-ray diffraction. 1 crystallizes in triclinic, space group P1 with a = 8.790（5）, b = 10.486（5）, c = 13.305（5） ?, α = 87.391（5）, β = 82.925（5）, γ = 81.841（5）o, V = 1204.2（10） ?3, Z = 2, C27H23FN4O5Co, Mr = 561.42, Dc = 1.548 g/cm3, F（000） = 578, μ（Mo Ka） = 0.769 mm-1, R = 0.0415 and wR = 0.1043. In 1, each 1,4-chdc anion bridges two neighboring Co（Ⅱ） atoms to give a chain structure. The L ligands are attached on one side of the chain through chelating the Co（Ⅱ） atoms, and are stacked with those of an adjacent chain through π-π interactions, yielding a double-chain structure. The double-chain structures are linked into a supramolecular layer structure through N–H···O hydrogen-bonding interactions between the adjacent double-chain structures. Moreover, the thermal behavior of 1 was also studied.

UHPC-RC节段组合梁的抗弯性能分析

为研究低预应力度条件下,不同节段接缝的超高性能混凝土-钢筋混凝土(ultra-high performance concrete-reinforced concrete,UHPC-RC)组合梁的抗弯性能,文章基于ABAQUS有限元软件,建立UHPC-RC节段组合梁的基准有限元模型,并利用已有的试验数据验证该模型的合理性。节段接缝分别为平面干接缝、平面胶接缝、齿键干接缝和齿键胶接缝,在基准有限元模型的基础上,进一步研究节段接缝类型对组合梁抗弯性能的影响。研究发现,在四点受弯加载方式下,接缝的几何特征(平面或齿键)对组合梁的极限荷载和开裂荷载影响较小,环氧树脂胶的使用对组合梁的抗弯性能影响较大。

Factors Influencing Preventive Behaviors of Mothers for Diarrhea in Children Aged 1-5 Years in Buol District, Indonesia

This study aims to determine the factors related with mothers＇ behaviors in preventing diarrhea in children aged 1-5 years inBuol District. This was a cross-sectional survey design with health belief model as the conceptual framework. A total of 300mothers were selected by using purposive sampling method based on criteria. Mothers were interviewed by using astructured questionnaire during October to November 2015. A chi-square （X^2） test was used to determine a significantassociation between independent variables and dependent variable. The finding showed that 68.3% of mothers hadgood behaviors in preventing diarrhea. The factors significantly related to mothers＇ behaviors included perceivedsusceptibility to diarrhea, perceived severity of diarrhea, perceived benefits of diarrhea prevention behaviors, and perceivedbarriers of diarrhea prevention behaviors CP 〈 .01, p 〈 .01, p 〈 .01, and p 〈 .01 respectively）. Further, mothers had highperception to comply with diarrhea prevention behaviors. Those who perceived that diarrhea prevention behaviors werehighly beneficial to their children had good behaviors in preventing diarrhea. However, taking certain actions must considernegative aspects.

Energy Balance-related Behaviors Are Related to Cardiometabolic Parameters and Predict Adiposity in 8-14-year-old Overweight Chinese Children One Year Later

To identify target energy balance-related behaviors（ERBs）,baseline data from 141overweight or obese schoolchildren（aged 8-14years old）was used to predict adiposity[body mass index（BMI）and fat percentage]one year later.The ERBs included a modified Dietary Approach to Stop Hypertension diet score（DASH score）,leisure-time physical activity（PA,days/week）,and leisure screen time（minutes/day）.Several cardiometabolic variables were measured in the fasting state, including systolic blood pressure （SBP）, diastolic blood pressure （DBP）, blood glucose （GLU）, total cholesterol （TC）, triglycerides （TG）, low-density lipoprotein （LDL-C）, and high-density lipoprotein （HDL-C）.

Effect of Stretching - Setting Treatment on Dyeing Behavior of Wool

Changes of dyeing behavior of wool after stretching - setting treatment are studied.Effects of stretching - setting on wool structure are analyzed.It is concluded that stretching - setting treatment not only reduces wool diameter and increases wool length,but also brings about low-temperature dyeing of wool.

Rheological Behavior of Zero Cement Al_2O_3-MgO Castables

Al2O3 -MgO castables have been widely used for working linings of steel ladle due to their superior hot strength and corrosion resistance. In this- work, effects of＂ microsilica, ultrafine alumina and MgO fines additions on the rh, eological behavior of the castables were investi- gated by means of IBB rheometer V1. 0 to measure torque （shear stress） under varying shear rates. The re- sults show that rheological properties of castables at varying shear rates are significantly improved with increase of microsilica additions （from 1 mass% to 5 mass% ） and corresponding decrease in water addition; there is only little change in rheological behavior with variation of ultrafine alumina and MgO fines additions. Optimum ultrafine alumina and microsilica additions are recommended for castables with good rheological behavior.

Behavior of Cl^(-) Ions in Ag(SO_3)_2^(3-) Solution

l- ions behavior in Ag(SO_3)3-2 solution was studied. The mechanism of Ag particles formation in the solution was discussed, and factors affecting its formation were investigated.

Synthesis,Crystal Structure and Thermal Behavior of 4,5-Dimethoxy-2-(dinitromethylene)imidazolidine

A new energetic material,4,5-dimethoxy-2-（dinitromethylene）imidazolidine（DMDNI）,was synthesized by the reaction of 4,5-dihydroxyl-2-（dinitromethylene）-imidazolidine（DDNI） and methanol,and structurally characterized by single crystal X-ray diffraction.DMDNI crystallized in triclinic space group P1,with crystal data a=0.4324（4） nm,b=1.3599（11） nm,c=1.7503（14） nm,α=77.406（14）°,β=84.494（15）°,γ=87.976（14）°,V=0.9997（14） nm 3,Z=4,μ=0.140 mm-1,F（000）=488,D c =1.556 g/cm ^3,R 1 =0.0773 and wR 2 =0.1574.Thermal decomposition of DMDNI was studied,and its thermal decomposition process was divided into two stages.The first stage was a melting process and the second stage was an exothermic decomposition process.The enthalpy,apparent activation energy and pre-exponential constant of the exothermic decomposition reaction are-491.5 J/g,142.3 kJ/mol and 10 14.24 s^-1,respectively.The critical temperature of thermal explosion is 162.47 °C.DMDNI has a lower thermal stability than DDNI but it is close to that of 4,5-diacetoxyl-2-（dinitromethylene）-imidazolidine（DADNI）.

Acid-base behavior of cryptand 1, 4, 7, 10, 13, 16, 21, 24-octaaza-bicyclo [8, 8, 8] hexacosan-3, 8, 12, 17, 20, 25-hexone and complex formation

The bicyclic cryptand 1,4,7, 10,13,16,21, 24-octaaza-bigcyclo [8, 8,8] hexacosan-3, 8, 12, 17, 20, 25-hex-one (COBH) bearing diaminoethane groups along the eight-atom bridges was synthesized. The structure consists of discrete neutral macrobicyclic units; the two cycles share the two tertiary amine nitrogen atoms, which exhibit an endo-cndo conformation. Three identical branches formed by 1, 2-diaminoethane link the two tertiary amine groups. The protonation reactions of cryptand (COBH) and its complex formation with copper (II) were investigated by potentiometry in water and in a DMSO/water (80:20 in mass ratio) mixture as solvents. The cryptand acts as a his-base through its two N-bridgehead and exhibits a strong cooperativity that favors the first protonation and makes the second one difficult (△pK= 5.0). An inward rotation of the amide groups to form hydrogen bonds accounts for this cooperativity. The interaction of COBH with copper (II) leads to several binuclear complex proton contents.

Intelligent method to develop constitutive relationship of Ti-6Al-2Zr-1Mo-1V alloy

The isothermal compression tests were carried out in the Thermecmastor-Z thermo-simulator at temperatures of 800, 850, 900, 950, 1000 and 1050 ℃ and the strain rates of 0.01, 0.1, 1 and 10 s-1. The influence of deformation temperature and strain rate on the flow stress of Ti-6Al-2Zr-IMo-IV alloy was studied. Based on the experimental data sets, the high temperature deformation behavior of Ti-6A1-2Zr-IMo-IV alloy was presented using the intelligent method of artificial neural network （ANN）. The results indicate that the predicted flow stress values by ANN model is quite consistent with the experimental results, which implies that the artificial neural network is an effective tool for studying the hot deformation behavior of the present alloy. In addition, the development of graphical user interface is implemented using Visual Basic programming language.

Video-based measurement and data analysis of traffic flow on urban expressways

A new video-based measurement is proposed to collect and investigate traffic flow parameters. The output of the measurement is velocity-headway distance data pairs. Because density can be directly acquired by the reciprocal of headway distance, the data pairs have the advantage of better simultaneity than those from common detectors. By now, over 33 000 pairs of data have been collected from two road sections in the cities of Shanghai and Zhengzhou. Through analyzing the video files recording traffic movements on urban expressways, the following issues are studied：laws of vehicle velocity changing with headway distance, proportions of di0erent driving behaviors in the traffic system, and characteristics of traffic flow in snowy days. The results show that the real road traffic is very complex, and factors such as location and climate need to be taken into consideration in the formation of traffic flow models.

Experimental Study on Momentum Transfer of Surface Texture in Taylor-Couette Flow

The behavior of Taylor-Couette （TC） flow has been extensively studied. However, no suitable torque prediction models exist for high-capacity fluid machinery. The Eckhardt-Grossmann-Lohse （EGL） theory, derived based on the Navier-Stokes equations, is proposed to model torque behavior. This are the significant energy theory suggests that surfaces transfer interfaces between cylinders and annular flow. This study mainly focuses on the effects of surface texture on momentum transfer behavior through global torque measurement. First, a power-law torque behavior model is built to reveal the relationship between dimensionless torque and the Taylor number based on the EGL theory. Second, TC flow appa- ratus is designed and built based on the CNC machine tool to verify the torque behavior model. Third, four surface texture films are tested to check the effects of surface texture on momentum transfer. A stereo microscope and three-dimensional topography instrument are employed to analyze surface morphology. Global torque behavior is measured by rotating a multi component dynamometer, and the effects of surface texture on the annular flow behavior are observed via images obtained using a high-speed camera. Finally, torque behaviors under four differentsurface conditions are fitted and compared. The experi- mental results indicate that surface textures have a remarkable influence on torque behavior, and that the peak roughness of surface texture enhances the momentum transfer by strengthening the fluctuation in the TC flow.

Lean Healthy Children with Short Stature Have Distinct Eating Patterns

Nutrition plays an essential role in normal linear growth in children. Knowledge of the eating styles and dietary consumption of healthy short children from developed countries is scarce. The aim of this study was to investigate the dietary patterns in idiopathic short stature （ISS） and relatively low weight children compared to children with normal stature and weight. This research is a case-control study of 86 pre-pubertal healthy children, mean age 5.9 ± 1.5 years. The study group comprised 43 ISS children; 43 age-matched children with normal stature and weight served as controls. Outcome measures included： dietary patterns and physical activity. The absolute daily average energy, protein and carbohydrate intake was significantly lower in the ISS children （P 〈 0.05）; after correcting for body surface area, no significant differences were found between groups. Intake of micronutrients calcium, iron, zinc, vitamin A and vitamin C, expressed as percentage from Recommended Dietary Allowance, was significantly lower in the ISS children （P 〈 0.05）, who had lower food responsiveness, higher satiety responsiveness, lesser enjoyment of food and were slower eaters （P 〈 0.001）. Physical activity was sedentary in both the ISS cases and controls. Our findings in healthy, pre-pubertal, relatively lean ISS children point to a distinct eating pattern with no alteration in physical activity. Understanding the differences in dietary intake and eating behaviors may be beneficial in the development of targeted nutritional intervention for lean ISS children.

Potent protection of Danshensu (β-3, 4-dihydroxyphenyl-lactic acid) against excitotoxic effects of maternal intragastric administration of monosodium glutamate at a late stage of pregnancy on developing mouse fetal brain

Recent studies have demonstrated that ferulic acid[3-（4-hydroxy-3-methoxyphenyl）-2-propenoic acid]and sodium ferulate produce protective effects against glutamate-induced neurotoxicity in adult mice.Danshensu（β-3,4-dihydroxyphenyl-lactic acid）has a similar molecular structure and pharmacological action to caffeic acid.This study aimed to validate the protection conferred by Danshensu against excitotoxic effects of maternal intragastric administration of monosodium glutamate at late stages of pregnancy in the developing mouse fetal brain.Behavioral tests,as well as histopathological and immunohistochemical examination of hippocampi were performed in filial mice.Results revealed that maternal intragastric administration of excessive monosodium glutamate（1.0,2.0,4.0 g/kg body weight）at a late stage of pregnancy resulted in a series of behavioral disorders（hyperactivity,lesions of learning and memory,and disturbance in cooperation of movement ability under high-altitude stress）,histopathological impairment（neuronal edema,degeneration,necrosis,and hyperplasia）and molecular cellular biological changes（upregulated expression of N-methyI-D-aspartate receptor type 1 and neuropeptide Y in the hippocampal region of the brain of the filial mice from mothers treated with monosodium glutamate）.Simultaneous administration of sodium Danshensu partially reversed the effects of monosodium glutamate on the above mentioned phenomena.These findings indicate that sodium Danshensu exhibits obvious protective effects on the excitotoxicity of monosodium glutamate.

Synthetic sensitivity analysis of high frequency radiation of 2011Tohoku-Oki(MW9.0) earthquake

Frequency-dependent rupture behavior of sub- duction zone interplate megathrust faults has been observed by back-projection method in different frequency bands （from 0.05 to 5 Hz）. It has been suggested that the down-dip region of the Tohoku megathrust radiated strongly at high frequencies （〉10 Hz） compared with that of the up-dip region. By assuming the same source tirne function of each fault patch, we perform a synthetic sensitivity analysis to compare the energy received from the shallower parts （and further way from the receiver sites） with that frona the deeper parts （and closer to the receiver sites） of the rupture. Our results indicate that regional onshore recordings are probably not adequate to constrain the presence of far-off shore high frequency radiations because of the strong attenuation of this region.

Preparation of c-Axis Oriented LiNb_(1-x) Ta_xO_3 Films on Si(111) Substrates by a Modified Sol-gel Process

In this work, we succeeded in the preparation of LiNb 1- x Ta x O 3 films on Si(111) substrates by means of sol gel process, and the usual sol gel process for the preparation of LiNbO 3 and LiTaO 3 films on Si substrates was improved by adding a 33% aqueous solution of CH 3CH 2OH to the mixed sols of LiNb(OCH 2CH 3) 6 and LiTa(OCH 2CH 3) 6 . The crystallization behavior of LiNb 1- x Ta x O 3 films on Si(111) substrates has been studied. Highly c axis oriented LiNb 1- x Ta x O 3 films have been obtained within the tantalum composition range of \{0< x <0 33\}. Some factors such as the hydrogen termination of the silicon surface, the RTP annealing process that provides the unidirectional heat flow and the preheating temperature are discussed to analyze the crystallization of the c axis oriented films.

Oxidation of Al_2O_3-30%TiCN-0.2%Y_2O_3 Composite

The oxidation behavior of Al2O3-30%TiCN-0.2%Y2O3 composite and its effect on high temperature bending strength was studied. The result indicates that the mass gain during static oxidation of the material under normal atmosphere follows the parabolic law. Oxide increases with increasing temperature and prolonging time. It has good oxidation resistance. The product of oxidation of the material is TiO2. Therefore, the volume of the material expands. The oxide film is destroyed because residual stress inside the oxide film is released. Proper oxidation is beneficial to the improvement of bending strength of Al2O3-30%TiCN-0.2%Y2O3 composite. The strength increase is up to 4.5%.