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This paper presents a method of production and properties of ethyl esters as well as the differences between them and methyl esters.
The properties of rapeseed oil are mainly determined by the way in which it is obtained from seeds.
The most important factors which affect seeds quality include: • ripeness, • presence of damaged seeds, • humidity of seeds after harvest and during the storage period, • storage conditions.
Ethyl esters have a lower melting point as compared to the more popular methyl esters, which results in the former’s superior properties at low temperatures [6].
Moser: Biodiesel production, properties and feedstocks.

For this purpose a model of linear, time-invariant, mass-damper-spring mechanical system was defined, schematic of which is showed in the Fig 1.
Schematic of a mechanical system used for simulation The model consists of eight masses interconnected with each other using spring (proportional stiffness) and damper (proportional damping) elements.
Dynamic properties of examined model Mode no.
Some minor residual traces of can be spotted in the remaining frequency bands, however their amplitude does not affect the general image.
Construction of modal filter requires a knowledge of modal parameters of a system (natural frequencies and damping factors) which can be estimated by performing a modal analysis.

Monitoring Method of Stray Current in Coal Mine on Optical Fiber Sensing Technique Cai Lihuaa, Li Weib and Fang Haifengc School of Mechanical and Electrical Engineering, China University of Mining and Technology, Xuzhou, Jiangsu, 221116, China acailihua1984@163.com, bliweicumt@163.com, cfhf@cumt.edu.cn Keywords: Stray current, Optical fiber sensors, Magneto-optic effect, Linear birefringence Abstract.
Introduction Safety production is affected seriously by stray current, which is produced by the DC electric locomotive haulage network in coal mine.
The fundamental rule of the optical fiber sensing is that characteristic parameters (amplitude, phase, polarization state, wavelength, etc) presenting optical wave when light propagates in an optical fiber changes directly or indirectly due to environmental factors (temperature, pressure, magnetic field, displacement, rotation, etc ), thereby, optical fibers are used as sensing elements to detect various physical quantities.
It has a great influence on the system with the linear birefringence caused by fiber bending, which creates the output of the polarization state is not stable, and which affects the measurement accuracy and reduces the linearity of the system output curve.
The linear polarized light with high cylindrical birefringence optical fibers travel with high extinction coefficient which is in random azimuth angles of incidence, in the meantime, the circular-birefringence brought by torsion can resist the influence of fiber polarization property from external disturbance to a certain extent, therefore, high cylindrical birefringence optical fiber is suitable to be applied in the fiber-optic current sensor field.

These comprise advection, hydrodynamic dispersion (mechanical dispersion and molecular diffusion), adsorption, precipitation, and complexation [4].
Mechanical Dispersion Water molecules in a porous medium follow different paths; therefore, each encounters different flow conditions.
These variations in particle flow velocities are responsible for pollutant spreading, a mechanism known as mechanical dispersion [10].
In this work, the effluent dispersion model in porous media described in [12] was utilized, along with the following fundamental assumptions, considering the physical and chemical processes associated with contaminant migration in the soil: · The soil is considered a saturated porous medium, meaning all pores are fully filled with water; · Contaminant flow through the soil is transient and two-dimensional; · Contaminant release is continuous; · The physical properties of the contaminant medium and soil are considered constant (homogeneous); · The advective effect of the contaminant in the X direction is negligible compared to the diffusive term; · Mass flux in Y is much greater than in X; · There is no migration of contaminants through the boundaries of the X axis; · Diffusive processes in the soil are negligible compared to diffusion in the contaminant; · A uniform velocity profile is considered for contaminant flow.
Conclusions Groundwater pollution affects different ecosystems that depend on this environment, making it extremely necessary to study methods that predict how it can be reached through pollutants.

Anisotropy of Bending Properties in Industrial Heat-treatable Extruded Aluminium Alloys K.
A few additional tests were executed to investigate the effects of the extrusion process on the bending properties.
Sample preparation for EBSD includes grinding, mechanical polishing and electro-polishing.
Results and Discussion Mechanical Testing.
Table 2 Tensile properties for the different alloys: yield stress, ultimate tensile stress, uniform tensile strain, fracture strain, area reduction at fracture and r-value.

Mechanical test demonstrates that compressive strength at 28 days is over 70Mpa.
Raw meal proportion with lime saturation factor (LSF) of 0.76, Silicate modulus (SR) of 4.63 and Aluminate Modulus (AR) of 1.01 is shown in Table 2.
Finally, the mechanical properties of cement, using 4cm´4cm´16cm mortar specimens with water to cement ratio of 0.5, were examined at age of 3 days, 7 days and 28 days respectively.
Figure 7 shows that the clinker, with many voids, is characterized with dominating belite phase, unidentifiable alite phase and minor other phases. 4.5 Physical and Mechanical Properties of Active Belite Cement Physical properties, such as setting time, flowability and water demand of active belite cement, were evaluated in accordance with Chinese Standards.
Six active belite cement clinkers sintered at various temperatures has a lime saturation factor of 0.76, silicate modulus of 4.63, and aluminate modulus of 1.01.

Setting-up Wireless Communication System for Mine Rescue Robots Xusheng Xue1, a, Hongwei Ma1, b, Juan Wei1, c 1School of Mechanical Engineering, Xi'an University of Science and Technology, Shaanxi, 710054, China.
Introduction Coal mine production is always accompanied with danger at any time, and many factors deadly threaten people’s life and property.
Fig. 1 A network model for the disaster-affected underground wireless communication The networking system is composed of two-level coal mine rescue robot system, coal mine rescue robot detection system, wireless communication monitoring system, the combination of software and hardware of the “roly-poly” wireless repeater and distributing device.

In addition, external factors such as regular earthquakes contribute to infrastructure breakdowns.
Extremely high corrosion was found to be a major factor in the collapse of the reinforced concrete, which led to the reinforcement cracking.
The distribution of potential values observed on a concrete surface is subject to the influence of various external factors, including the thickness of the concrete layer and the level of density of the concrete mixture [10], [11].
The combining of liquid and solid-based electrodes exhibits various advantageous characteristics, such as an efficient fabrication method, reliability, and disposable properties.
Ariffin, “Corrosion Risk Assessment of Public Buildings Affected By the 2004 Tsunami in Banda Aceh,” Journal of Earthquake and Tsunami, vol. 07, p. 1350004, (2013) [10] H.

The electrical and optical properties were determined using a four point probe technique and UV-VIS-IR spectrometry, respectively.
Introduction Nanoscaled thin films open new opportunities for the design of materials with novel or enhanced properties.
Nanocomposite thin films consisting of hard constituents can exhibit mechanical properties that are critical to magnetic storage devices, cutting tools, and biomedical implants [2].
Multilayer thin films of alternating nanoscaled carbon layer and metal layer provide excellent wear and friction properties [3].
As a result, both factors of sputter yield and thermalization distance indicate that the Pt film would have the highest deposition rate while the carbon film would have the lowest deposition rate.

In recent years, with electronic technology, measurement and control technology, mechanical dynamics, and other disciplines of rapid development, make the automobile suspension system vibration isolation from the traditional passive to active vibration control.
The mechanical model of automobile suspension In the research of automobile suspended frame nonlinear vibration characteristics research must be established according to the mechanical model of automobile suspended frame commonly used automobile suspended frame model has three: namely 1/4 vehicle suspension model, 1/2 car suspension model and vehicle suspension model.
In order to simulate the quality, tire body due to the stiffness and damping coefficients of shock absorber change such as uncertain error, application h-infinity optimal control method can make the automobile suspended frame vibration control has strong adapt to the ability of uncertain factors [6].
Using the optimal control method to foresee, foresee a time choice to the control effect is affected.
Hefei university of technology and FangXiBang will fuzzy control technology application in automobile semi-active control suspension [9], in the real car in the process of application, vibration properties are better than those passive suspension.