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The Assessment of Subsurface Damage in Ground Optics by Chemical Etching Hui Yea, Wei Yangb,* School of Mechanical & Electrical Engineering, Xiamen University, Xiamen 361005, China ayhxmu@sina.com, b*oncefly@126.com Key words: optical manufacturing; subsurface damage evaluation; chemical etching Abstract.
Introduction Hard brittle fused silica is widely used in high power laser system thanks to its excellent performance and mechanical properties.
Subsurface damage (SSD) of optical elements, created during the traditional grinding and polishing process, has been a key factor influencing optical quality and performance [1-3].
These methods are generally easy-operated and cost-effective, but the measuring resolution is associated with external factors such as temperature or acid concentrations.
The results accuracy is affected by the judge of etching time when the cusps get the deepest depth.

Though, especially the interface quality of a hybrid joint is a crucial factor, which determines the overall quality of such lightweight structures.
This paper focuses on certain polymeric materials and their processing conditions on the adhesion properties in combination with differently pre-treated aluminum sheets [5].
Aluminum surface quality Properties Unit unstructured laser structured Ra [µm] 0.15 0.32 Rz [µm] 0.34 1.01 Measurement length [µm] 830.00 830.00 Surface profile length [µm] 831.21 832.88 Lstructured - Lunstructured [µm] 1.68 [%] 0.20 Fig. 5: Average surface profile of unstructured and laser structured aluminum sheets Mechanical properties of the tensile test samples.
Tensile strength Strain at tensile strength [MPa] [%] TPE-U 279.40±5.89 433.20±7.28 PE-mod 078.88±5.59 369.50±2.15 TPE-S-mod 022.98±0.94 093.66±2.16 Fig. 6: Stress vs strain curve as well as tensile strength and strain at tensile strength for tensile test samples made from the different investigated polymeric materials Mechanical properties of the double-lap joints.
It might be that the lasered groove depth was too low to cause severe mechanical interlocking [6].

Synthesis of High Aspect Ratio Iron Oxide Nanoparticles Using Water in Oil Microemulsion M.Suhafria , I.I.Yaacob b Centre for Nanotechnology, Precision and Advanced Materials (CNPAM) Department of Mechanical Engineering, University of Malaya, Malaysia a ok_ker@yahoo.com, biskandar@um.edu.my Keywords: High aspect ratio; Microemulsion; Maghemite; Superparamagnetic; Abstract High aspect ratios maghemite of iron oxide nanoparticles were prepared using water in oil microemulsions.
This is mainly because of the dependence of their properties on the shape and size of the inorganic nanocrystals. [1].
The sizes are different from the diameter or length of particles observed by TEM and cannot be explained on the basis of shape factor.
This is due to the various contributions such as particle size and shape defects including pores, dislocation and point defects that affected the X-ray broadening line. 25 35 45 55 65 75 85 2Theta (degree) Intensity SD (24hrs) SC (12hrs) SA (4hrs) (220) (311) (400) (422)(511) (440) Figure 2: XRD diffraction of SA (4hrs), SC (12hrs) and SD (24hrs) Hysteresis curves of the samples measured by AGM at room temperature are shown in Figure 3.
-40 -30 -20 -10 0 10 20 30 40 -10000 -5000 0 5000 10000 H (Oe) M (emu/g) SA (4hrs) SD (24hrs) SC (12hrs) Figure 3: Hysteresis curve of the samples with the applied field at 10kOe Summary High aspect ratio maghemite (γ-Fe2O3) nanoparticles with superparamagnetic properties were successfully synthesized using water in oil microemulsions.

The connatural aero-elasticity divergence and the strong aerodynamic coupling as well as many uncertain factors in mechanical environment, give the VFSW Tailless configuration UAV complicated dynamic characteristics.
During the process of transformation, if there is dynamic response that isn't expected, flight quality and even safety will be seriously affected.
Under effect of two factors, aerodynamic center point of aircraft begins to move back
During the process of transformation, variation of gravity center is mainly influenced by following factors, geometric shape, installment position of mechanism, ratio of mass of wings to gross mass of aircraft, and mass distribution of wings.
Aircraft Flying Property Handling Qualities and Control [M].

The quality of the dendritic structure affects the microsegregation besides the mechanical properties at elevated temperature.
This paper deals only with those factors of macrosegregation which are originated in the change of temperature field of solidification in time and in directions.
But the real occurence depends on other factors as well (fluid flow, nucleation etc.).
In the solidification process explained above different factors sometimes play oppositional roles.
Among the beneficial factors the lower thermal gradient in the final solidification stage can be mentioned.

The different process conditions also make the coating effect and the electrical properties of the composites different.
Doping of protonic acid was an important factor affecting the conductivity, different concentrations of aniline to provide the acidic environment was different.
Conclusions The process conditions of PANI coated nickel fibers and electrical properties of coated nickel fibers were investigated.
Shi, and Q.Guo, Preparation and Electrical Properties of Graphene Coated Glass Fiber Composites.
Yang, Preparation and Electromagnetic Properties of PANI Coated Short Carbon Fibers.

The effect of additive on crystal morphology can be observed in the variation of crystal habit as well as variation in their physical and chemical properties [3].
The change of crystal morphology also can also affect the downstream processing and formulation of final crystal products [4].
Examination of atomic interaction based on the visible hydrogen bond network for (011) face demonstrated that glycine molecule disrupted the hydrogen bond network, hence affecting both the columbic and van der Waals interaction.
The Attachment Energy as a Habit Controlling Factor I.
Physicochemical Properties of Zwitterionic L- and DL-Alanine Crystals from Their Experimental and Theoretical Charge Densities.

Compared with traditional mechanical valves, the magneto-rheological control valve has some benefits such as simple structure, small bulk, easy to control, fast answer speed, low work noise, resistance abrasion, high reliability and low cost.
Too small particulate diameter is result to low MR fluid saturation magnetic induction intensity, which will affect whole performance of MR fluid.
After magnetic fields affect, icon particles are magnetized and array along magnetic fields direction.
This intelligent material flows fluently when there is no magnetic field, at this time, the valve opens; however, when the current is applied, it brings strong magnetic field, apparent viscosity of the MR fluid increases in a flash (Milliseconds), MR fluid takes on solid property.
Mathematical Model Pressure drop of MR fluid passing through the ring damping gap of MR valve is [10]: dLc Rd QL P aya τ π η +=∆ 3 1 6 (1) In formula, η-viscosity of null field; Q -inlet volume flow; aL -length of ring damping gap; d -thickness of damping gap; n Y aB=τ -yield stress of MR fluid under magnetic field; R -disk radius; c -correction factor, ranging from 2 to 3.

In silicon, where the power laws also hold well, there is some doubt whether the surface properties of doped crystals correspond to the bulk properties.
A brickwork array of square grains, alternately hard and soft because of alternating Schmidt factors which make shear under a tensile stress harder or easier.
All rows can be similarly treated, and the brickwork array can be randomised along the lines AA without affecting the argument leading to eq. (20).
Although the difference in Schmidt factors affects the primary slip system, activity on the several secondary systems which make up the rotational flow is plausibly equally possible in both sets of grains.
Cottrell: 1964, Mechanical properties of Matter (John Wiley, 1964 see section 9.4) [3] M.

Currently, mechanical and electronic methods are usually taken to test the underground pressure of oil and gas wells [1], these methods need to suspend the equipments by steel wire after closing the oil wells and taken out after testing, which can not achieve real time logging, and the data interpretation seriously lags logging, affecting seriously normal production.
Selection of the material is crucial to the property of elastic component.
Consider the factors above, stainless steel[5] is chosen as the material of convoluted diaphragm, the modules of elasticity is , which is constant below, linear expansibility is , which is comparatively small.
The main parameters that influent the figure of the convoluted diaphragm are figure factor ,working radius , thickness of the diaphragm ,the depth of corrugation , distance of corrugation , the quantity of corrugation .
In this work, through finite element analysis to the convoluted diaphragms with and different , the properties are analyzed.