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Note that solid propellant grain used in rocket launch vehicle, in general, is a thick-walled hollow cylinder made of viscoelastic materials [1].
The authors’ simulations provide detailed insight into how flow structure, viscoelastic stresses, and viscoelastic work change with increasing Deborah number.
This is particularly true in the case of solid propellant grains.
[6] Chu, Hung-Ta, and Chou, Jung-Hua "Poisson ratio effect on stress behavior of propellant grains under ignition loading", AIAA Journal of Propulsion and Power Volume (27)(3), 2011, pp. 662
Saravana Kumar, Numerical Studies on Viscoelastic Characterization of Solid Propellant Grain, 15th Asia Pacific Vibration Conference, 2-6 June, 2013, ICC Jeju, Korea

Observations of the fracture by SEM reveal that the dynamic fracture surface for Mg-3.3Li alloy mainly appears to be brittle fracture along grain boundaries.
However, for the Mg-14Li alloy, the fracture is mainly of ductile in both areas, and there are number of precipitates distributing on the fracture surface (Fig. 2c、d).

It is probable that a sol-gel spin coating process at 200 °C produced dense, irregularly shaped Bi2O3 grains.
With metal ions doped into Bi2O3, the particle size and grain shape can be improved while the structure can be stabilized.
In JCPDS file number 81-0563 [20], 10.25 Å is reported after annealing the film, and the results of XRD are in good agreement.
The figure shows several dense morphologies along with fine-grained microstructures.
It is likely that Bi2O3 grains were formed in dense irregular shapes using a sol-gel spin coating technique at 200 °C.

The results indicate that the vertical soil pressure on trench culvert is not always lower than the theoretical calculation value instead, it is related to and varies in nonlinear manner with a number of elements including filling height, width and slope of trench, dimensions of culvert, physical properties of backfill material, and stiffness of foundation, etc.
Foreword Load on culverts under high-fills is normally relevant to a number of elements especially the height of fill and the volume weight of backfill material.
Effects of cyclic freezing and thawing on volume changes and permeabilities of soft fine-grained soils[J].

Ultrasound technology is used as a modern and very environment friendly process in an increasing number of applications and processes of the chemical industry.
Ultrasonic techniques have been used in the extraction of chitin [4], a protein in grain sorghum [5], and the synthesis of biodiesel from used cooking oil [6].
In the IR spectra also appeared absorption at wave number 1565.30 cm-1 which is the bend vibration N-H of NH2.
The -CH3 bend absorption band at wave number 1319.37 cm-1 is appear but with a weaker intensity, it indicates the occurrence of deacetylation process that led to the loss of most of the methyl groups,-CH3.

Intorduction With the advance of science and technology, especially in recent years, aerospace manufacturing, atomic energy, electric power, petroleum equipment etc the rapid development of the industry, the machine and its spare parts material performance put forward higher request. and titanium alloy with its excellent mechanical properties, KangFuXing can, diamagnetic can, resisting high temperature oxidation performance and so on, in the industry has rapidly application..demand titanium alloy tube parts also more and more, especially with high precision requirements of the titanium alloy tube parts number is more and more titanium alloy is is a kind of hard processing material, it's the cutting itself is very difficult, talked about deep hole precision processing that is a difficult task. therefore, how to realize the titanium alloy for deep hole precision machining is the current cheng to solve the problem. this paper through the test of TC11 titanium alloy to choose the suitable
Table 1 The mixed stone proportion of elements Stone Numbers 1# 2# 3# 4# 5# 6# 7# 8# 9# 10# 11# 12# 13# 14# 15# Abrasive composition WA GC SA Each composition The proportion （%/%） 100 100 100 note : 1#-3# Main abrasive for single crystal jade ; 4#-9# Main abrasive for silicon carbide; 10#-12# Main abrasive for white corundum 2.2 sample method and condition The mixed stone are installed in the self-designed deep hole honing tool in the body, the processing parts installed in modified type horizontal deep hole honing machine, specimen aperture forΦ31~35mm，depth 500mm，honing dosage for rotational speed v=20m/min，reciprocating feed speed=10m/min，and the stone constant pressure radial feed way,each stone are continuous complete nine times radial feed cycle after contrast measurement,honing cutting fluid choose kerosene. honing torque is measured by in the drill pipe installed on homemade torque detection device,the measurement system to accomplish data processing
The results and analysis 3.1 Mixed oilstone grinding state before and after Table 2 Titanium alloy test results Stone Numbers Beforehoning diameter (mm) Honing diameter after (mm) Honing remove quantity(mm) Grinding except material volume (mm3) Grinding exceptoil stonevolume (mm3) Grinding ratio Honing torque (N, m) Than grinding can note 1 33.00 33.03 0.03 778 756 1.029 45.10 58.0 sticky 2 33.05 33.09 0.04 1038 832 1.248 39.50 38.1 sticky 3 33.11 33.15 0.04 1040 795 1.308 39.07 37.6 sticky 4 32.74 32.78 0.04 1029 635 1.620 45.51 44.2 Microadhesive, fragile 5 32.79 32.83 0.04 1030 576 1.788 45.31 44.0 Microadhesive, fragile 6 32.85 32.90 0.05 1290 583 2.213 46.30 35.9 Don'tstick, non-friable 7 32.68 32.72 0.04 1027 624 1.646 43.52 42.4 Microadhesive, fragile 8 32.62 32.66 0.04 1025 639 1.604 41.24 40.2 Microadhesive, fragile 9 32.58 32.61 0.03 768 560 1.371 35.86 46.7 Don'tstick, non-friable 10 32.44 32.47 0.03 764 638 1.197 42.40 55.5 sticky 11 32.48 32.51 0.03 765 640
same, in processing parts requirements under the condition of the same precision, using silicon carbide and single crystal corundum mixed stone processing with high efficiency. 2.3 Adhesion and crushing test results Adhesion and crushing test result case as below: Figure1 Honing after 2 # sticky oil stone Figure 4 Honing after 6 # micro adhesive stone Figure 5 Honing after 8 # oil stone Figure 6 Honing 15 # micro adhesive stone The adhesion situation can be seen, alumina content higher oil stone adhesion of the situation is more serious, is mainly due to corundum abrasive grinding of titanium alloy, formation of Ti2O3 and Al2O3 crystal structure with think, lattice parameter close, so produce titanium oxide and corundum has a strong affinity; meanwhile, Ti2O3 in corundum also can form Al2O3, Ti2O3 solution content,make titanium and corundum have strong combination, these are greatly enhanced the titanium and corundum grinding grain

Introduction Through the study of a large number of communication terminal products found that contact fretting failure is one of the main reasons leading to the invalid connector.
This is because when the contact pressure increases, the two contact surfaces move close to each other, contact number of spots increases so that the real contact area increases, reduce the resistance.
Table 2 Test results Test results Photos Numbers force(g) A(mA) V(mV) R(mΩ) State a 100 100 1.176 11.76 partial pressed b 100 100 550 5500 just pressed c 100 100 550 5500 just pressed d 100 100 3.506 35.06 crushed e 150 100 0.705 7.05 partial pressed f 150 100 0.635 6.35 crushed g 150 100 550 5500 just pressed h 150 100 0.961 9.61 crushed i 150 100 550 5500 just pressed j 150 100 3.506 35.06 crushed k 150 100 2.891 28.91 crushed (a) (b) (c) (d) (e) (f) (g) (h) (i) (j) (k) Fig.2 Photos of 70-150μm particles after pressed It is being seen from table 2, 70-150 silica particles results in a larger change.
The presence of silica particles is increased at least 3 times than clean samples; when other experimental conditions do not change only increase the contact pressure, regardless of grain contact resistance will decrease. 2.

Table .1 The granite residual soil weathering degree hierarchical table level number the soil composition and structure differences the engineering specification 1 Even the red soil layer Sand, gravel, clay 2 Checkered red soil Sandy clay powder, clay content is higher 3 Mottled clay layer Gravel, clay or silt, sandy powder locally for coarse sand in clay Combined part of about 75% of the total area of the region, mountainous hilly region of slope surface covered with widely, the residual soil thickness usually within 6 meters, affected by geological structure after the quake, shallow landslide in heavy rainfall weather easily happened.
Table.2 Earthquake eluvia soil the soil physical and mechanical properties Name Color thickness (m) Gravel particles （%） sand （%） silt （%） clay （%） ρ(g/cm3) C (kPa) Φ (°) e Sand clay Red-brown 0.5-7 0.1-28.0 20.9-47.0 10.7-38.0 22-55.6 1.57-1.90 8.9-70.0 12.0-35.0 0.8-1.07 Pink clay brown 5-15 15.0-34.0 10.0-55.0 8.0-38.0 10.5-34.0 1.63-1.78 8.9-50.0 18.6-33.0 0.72-1.13 silt Brown spots >10 15.0-47.0 42.3-67.0 8.0-30.2 4.0-13.0 1.66-1.93 10.0-40.0 24.0-35.0 0.63-1.04 On the grain size distribution of it in residual soil from top to bottom, with the increase of weathering degree, significantly reduce the content of clay, gravel content.Eluvia soil layers soil density from top to bottom with the reduce of void ratio increases gradually, basic is within the scope of 1.75 to 2 g/cm2, pore ratio is between 0.8 0.99 distribution, pore ratio is larger.Eluvia soil cohesion around from top to bottom with the loss of the clay content decreases, and the internal friction Angle are increased
The experimental principle and the result analysis This subject adopts the random simulation method, its basic principle is: the probability of an event can use a large number of trials to estimate the incident frequency, according to Tchebycheff procedure, cutting of large Numbers theorem, when the sample size is large enough, the frequency of the event can be considered as its probability.

By analysing a large number of soil physical parameters experimental data, the paper gives empirical value to estimate the compaction coefficient and water content base on the quality of the sample or D-value of the quality.
Increase compaction function can effectively overcome the resistance between the soil grain.
To guide field construction and improve the effect of compaction, a large number of on-site backfill soil physical parameters trials are necessary.

On the other hand, the number of end-of-life Li-ion batteries grows significantly and provides an additional source for these critical materials by recycling.
Due to the limited number of recovered materials and high energy input, the overall recycling efficiency is low.
The electric discharge in the reactor medium causes a shockwave penetrating the sample’s weakest points which are the mechanical bonds between materials and grain boundaries (fig. 1).