SHL10-1.29-AⅡ型锅炉加装过热器的节能分析

通过对锅炉加装过热器的改造，提高了锅炉的利用率，满足了生产需要，节约了能源，降低了产品成本，为该厂节省了大量资金，保证了锅炉的安全运行。     

护板弯曲模的设计及改进

针对护板的具体结构，设计了弯曲模，通过对其零件产生缺陷的原因分析，改进了原弯曲模结构，设计了摆块式弯曲模，由此，解决了原工艺中零件难以成形、角度回弹大、需要校正的难题，取消了需要预留工艺直边而进行的机械加工工序，降低了加工费用，提高了工效。     

脱挂梁传动特性的双频逼近及全自动化的实现

在齿轮齿条式脱挂梁设计中，建立了计算模型，编制了计算程序，求得了传动特性，并采用了双频逼近，创新了传动机构，实现了脱挂梁的全自动化。     

二级展开式齿轮减速器的润滑设计

为避免二级展开式齿轮减速器提前产生磨损失效，通过摩擦学设计，提出了最佳的润滑设计方法，解决了常见的润滑问题。通过安装一个带油轮，并优化其结构和安装尺寸，不但实现了搅油损失最小，而且限制了温度在最低的范围内。结果表明：该设计方法降低了摩擦，减少了磨损，提高了传动效率，而且节省了润滑油，缩小了整个箱体的结构尺寸。     

多轴浪形冲孔凹模加工工艺的改进

通过改进原有的加工工艺，采用先进加工设备，提高了多轴浪形冲孔凹模的加工精度，保证了产品的及时供应，同时提高了生产效率，缩短了生产周期，节约了原材料，达到了增产节约的目的。     

霍夫曼真空过滤器金属网带的国产化研究

分析了进口金属网带结构存在的不足，进行了改进设计，简化了原有结构，提高了效率，降低了成本，延长了使用寿命。     

高精度微型轴连轴承制造中的关键技术

轴是高精度微型轴连轴承的关键零件，结构复杂，精度高，加工难度大，尤其是沟道和台阶深内孔的磨削，有着极为严格的要求。为此，专门设计制造了特殊工装．对现有设备进行了重要的技术改造，满足了关键工序的加工需求，获得了理想的加工精度，达到了设计要求。     

起重机悬挂负载系统位置控制实验研究

在起重机工作时，负载围绕吊装线旋转，存在定位困难的问题，为此，以动量轮为执行机构，提出了一种基于角动量守恒定律的悬挂负载系统姿态控制方法。首先，对悬挂负载系统的机理与结构进行了研究，用欧拉角描述法推导出了系统的运动学方程，并基于角动量守恒定律对系统进行了动力学建模；然后，对系统的稳定性进行了研究，采用比例积分与比例微分(PI+PD)混合控制律，实现了对俯仰方向旋转位置的控制目的；并设计了比例微分(PD)控制律，抑制了外部干扰对俯仰方向旋转产生的摇晃；基于MATLAB的Simulink环境对系统进行了风力扰动下的仿真实验；最后，搭建了样机实验平台，进行了实际过程测试，结合测试结果对仿真结果进行了验证。研究结果表明：所设计控制律有效，位置控制角度误差达到10^-2量级；解决了负载旋转定位困难的问题，抑制了外部干扰对俯仰方向旋转所产生的摇晃。     

薄壁深腔零件上小螺孔的数控加工技术

利用数控加工中心在深腔薄壁零件上制作小螺孔时，极易断锥，致使小螺孔加工成本增加，无法进行正常生产。针对该问题，从工艺角度进行了具体分析，确定了合理的加工工艺路线，设计了必要的夹具，确定了合理的切削工艺参数，并采用了挤压丝锥，避免了非正常断锥和螺纹烂牙，大幅度提高了加工小螺孔的效率。     

柴油机磨合规范优化研究

根据机器的磨损规律，分析了机器磨合机理和磨合的相关因素，略去次要因素，通过简化磨损过程的解析模型，提出了磨合过程方程式，研制出新的磨合油和制定了新的磨合规范。实践表明，采用新的磨合规范不仅提高了磨合质量，而且大大缩短了磨合时间，降低了磨合成本，提高了生产率。     

The development of the tongue of the domestic goose from 9th to 25th day of incubation as seen by scanning electron microscopy

The general development of the tongue in birds was described by Lillie ( 1908 ) in chicken. Bryk et al. ( 1992 ) also studied the tongue development in chicken and they observed development of the conical papillae of the body. Our study aims to describe the timing of the development of the tongue morphological features in the domestic goose by using SEM methods. The tongue of the domestic goose is characterized by the widest variety of shape of the particular part of the tongue and mechanical papillae. Results indicated that the formation of the apex, body, lingual prominence, and the root of the tongue take place between the 10th and 19th day of incubation. The tongue elongates rapidly between the 16th and 18th day of incubation. Simultaneously, the median groove appears on the body and the lingual prominence and elongates towards the rostral part of the tongue. The conical papillae of the tongue develop gradually. On the body, the conical papillae develop from the caudal part of the body to the rostral part and on the lingual prominence from the median part of the prominence to the lateral part. Hair‐like papillae at the caudal surface of the body of the tongue remain primordial to the end of the incubation. Our studies on the morphogenesis of the tongue in the domestic goose revealed changes in shape of the particular part of the tongue and rapid pace of the formation of mechanical papillae. The tongue is completely develop before hatching and ready to collect food. © Microsc. Res. Tech., 2012. © 2012 Wiley Periodicals, Inc.     

用水平仪测量小台面对竖直轴线垂直度的方法

为了测量转台上边缘小平台对回转轴线的垂直度误差,首先在转台上建立了一系列坐标系,在考虑竖直轴线对水平面的铅垂度、边缘台面对竖直轴线垂直度的情况下,得出了平台坐标系对基准坐标系的姿态.并建立了水平仪读数与该姿态之间关系.将水平仪放置在小平台上,旋转轴系,得出了数直轴线的铅垂度误差、然后固定轴系不动、水平仪在小平台上旋转,得出了小平台平面的水平度误差.根据这个水平度和竖直轴线的铅垂度误差计算出了小台面对竖直轴线的垂直度误差.最后对测量的垂直度误差进行了误差分析.     

Levitation of a Soft Magnetic Sphere in a Field of Superconducting Coils Simulating an Axially Magnetic Torus

The ponderomotive forces affecting a soft magnetic sphere in a field of superconducting coaxial coils geometrically simulating a torus are investigated. To determine the forces, we used a mathematical model for the fields produced by an axially magnetized torus. The model includes calculating the polarization of the sphere with the averaging of the surface magnetic charges in two hemispheres and determining the forces affecting the effective magnetic charges of the hemispheres located in their centers of gravity. Thus, the model was reduced to a one-dimensional one. The calculations take into account the magnetic saturation of the sphere. The correctness of the dipole approximation of the calculation of the forces is shown. A correlation between the coordinates of the center of the sphere and the characteristic coordinates of the torus field was established. The areas of the stable equilibrium of the sphere are calculated. The applicability of the model is determined. The results of the calculations are compared with the experimental data.     

The depth of propagation of elastic deformation in rough bodies under frictional contact

The problem of the depth of propagation of the perturbations of the stress-deformed state in an elastic half-space produced when a periodic sinusoidal indenter slides along the surface to model the roughness has been studied by using the solution of the periodic contact problem of elasticity theory. Equations are derived for the stresses and deformations on the axes of symmetry at the centre of the contacting area and between the projections of the rough surface. Calculations indicate that roughness and friction forces only affect the thin near-surface layer of the elastic half-space and the effects rapidly decrease with distance from the surface. The thickness of this perturbed layer is independent of the friction forces, the radius of curvature and heights of the roughnesses and the elasticity properties. It depends only on the distance between the roughnesses. At a depth equal to a factor of 1.5 of the distance between the projections the deflection of the stressed state does not exceed 0.4% and the deformation is 1%. This has been shown to be characteristic for roughnesses in general. The results of the calculations are presented as graphs.     

蛇形机器人行波运动的研究

对蛇形机器人的行波运动机理进行了研究,基于Serpenoid曲线建立了蛇形机器人行波运动的形状控制模型、运动学模型、机构动力学模型及环境动力学模型,给出了求解过程。仿真结果表明：在行波运动中,各关节输入力矩大小呈周期变化,且随其与蛇体重心距离的增加而减小。蛇体中心关节的最大输入力矩为蛇形机器人所需最大输入力矩。对称关节输入力矩幅值变化规律相同,但相差不同;运动初始弯角保持不变,关节输入力矩随着环境摩擦因数的增加而增加。环境摩擦因数保持不变,关节输入力矩随着初始弯角的增加而减小。     

多环闭链可展机构尺寸调整方法

由于存在加工误差等因素,可展机构各连杆实际加工长度与理论计算长度往往不同,需要在装配时对其调整。多环闭链可展机构具有闭环多、环约束互相耦合、参数关系复杂等特点。为解决在尺寸调整时存在的高非线性、强耦合等问题,以均方根形式定义多环闭链机构的综合调整量,并以调整结构势能最小作为目标函数,推导出多环闭链可展机构尺寸调整的基本数学模型。根据实际调整方式,提出单向调整和双向调整两种计算模型。在此基础上,对多构态下多环闭链可展机构的尺寸调整方法进行研究。通过算例对上述方法和模型进行验证。结果表明,利用该方法得到的调整结果能满足可展机构多构态、多约束、多种调整方式的要求。研究成果有助于降低多环闭链可展机构的装配和加工难度。     

Identification of the shear-type displacement vector field and evaluation of its characteristics

A problem of identification of a shear-type solid flow is considered. Characteristics of the shear flow are determined on the basis of the initial displacement vector field. An algorithm of formation of a finite-size model displacement field of the shear type is given. A functional is proposed to search for the amplitude and direction of the shear flow for each local area of the vector field. The influence of the size of this area and of the degree of its overlapping with the shear flow on the error of shear angle measurement is shown. The choice of the local area size is analyzed. Functional operation is demonstrated by an example of the displacement field obtained in the case of compressive loading of the Hadfield steel single crystal.     

The stabilization of the position of the body of walking machinesLa stabilisation de la position du corps d'une machine marchante

This paper shows that in the task of the maintenance of constant orientation of the body of a walking robot the determination of the actual position of the body, i.e. absolute altitudes of its points and remoteness from the supporting surface, is the most complicated problem. Two possible systems of measurement and stabilization of the position by the height of the body of the walking mechanism are compared, i.e. a system of adaptation automatically adjusting the length of the supporting leg to the roughness of the terrain, and the system of the maintenance of constant remoteness of the body from the terrain. The inefficiency of a solitary application of any described system is revealed and the possibility of an accumulation of errors of the position of the body by the walking on the soft terrain is shown. Possible approaches for raising the quality of stabilization of the body by the walking are evaluated.     

Structure and expression of the transthyretin gene in the choroid plexus: a model for the study of the mechanism of evolution

Thyroid hormones are key regulators of brain differentiation and function. They permeate strongly into lipid membranes. However, a substantial portion of thyroid hormone is retained in the intravascular/extracellular compartments by binding to plasma proteins. In the brain, transthyretin is the most important of these proteins. This transthyretin is synthesized in the epithelial cells of the choroid plexus and exclusively secreted towards the brain. A net movement of thyroid hormones from the blood to the brain ensues. During evolution, transthyretin synthesis in the choroid plexus and the beginnings of a neocortex first appeared at the stage of the stem reptiles. The affinity of transthyretin for thyroxine increased and that for triiodothyronine decreased during evolution. This could augment the importance of deiodination for regulation of metabolism and gene expression by thyroid hormones in the brain. Successive shifts of the splice site at the 5' end of exon 2 of transthyretin precursor mRNA in the 3' direction led to a shortening of the N-terminal sections and to an increase in hydrophilicity of the N-terminal regions of transthyretin. This shift can be explained by a sequence of single base mutations. It could be an example for a molecular mechanism of positive Darwinian evolution. The selection pressure, which led to the expression of the transthyretin gene in the choroid plexus during evolution, might have been the maintenance of thyroid hormone homeostasis in the extracellular compartment of the brain in the presence of the greatly increasing volume of the lipid phase.     

RV减速器摆线轮齿廓曲线的曲率影响因素研究

以工业机器人为例,对RV减速器摆线轮齿廓曲线的曲率的影响因素进行了研究。根据微分几何理论,建立摆线轮齿廓的数学模型,采用坐标变换方法推导出摆线齿廓方程,分析了摆线轮齿廓曲线的凹凸特性,求出拐点的数学解析式。根据摆线齿廓方程计算出曲率和曲率半径的参数表达式,最后推导出可以概括摆线针轮传动的诱导法曲率公式。以RV-20E减速器为例,求解出凹凸区间曲率最大值和最小值,并利用Matlab编制程序进行仿真,详细分析了机构的偏心距、针齿半径、针齿分布圆半径、针齿数对拐点所在位置、曲率变化快慢的影响规律。通过对摆线齿廓的曲率的仿真分析,偏心距和针齿分布圆半径对摆线齿廓的曲率影响显著,同时也会影响拐点位置的变化,针齿半径对其有一定的影响,但影响较小,并且不会影响拐点所在的位置。研究结果为科学地选择摆线轮最佳参数和摆线针轮传动的设计提供了一种理论依据,具有一定的实用价值。