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The reason for these properties is that AlN is a covalently bonded material with a hexagonal 2H structures having no free electron in the crystal.
In a previous study, the physical and chemical properties of AlN were discussed in detail, but the machining characters were seldom involved.
The properties of lapping pad and abrasives are the essential factors to ensure the super-smooth surface.
Fig. 1 Schematic illustration of lapping system employed in this study Table 1 lists the experimental conditions for lapping of AlN ceramics, and Table 2 lists the mechanical properties of AlN ceramics employed in this study.
The gaps found on finishing surface caused in sintering could not be removed in the machining process, and have adverse influence on the properties of AlN substrate.

The characteristic technological and chemical properties of plasters protect supporting structure against weather and temperature extremes.
The mechanical purification is based on the high-pressure stream of water or hot steam.
In the contrast, impregnation with a depot effect has also preventive properties. [1] The vegetation of algae can be partially avoided, mitigated or delay using by appropriate type and structure of the plaster or by the using biocides. [6] Biocides additives can be added to the plaster.
The possibilities of rehabilitation of facades, including an appropriate base layer. [1] Properties of Plaster affecting the Vegetation of Algae and Fungi The final layer of ETICS is mostly acrylic, silicate, silicone and mosaic plaster.
Diffusion resistance factor μ-value [-] is in the range from 20 to 120.

Final user properties of concrete and other silicate composite structures are conditioned by their early-age history.
Introduction Over the past few decades a number of studies try to develop a computational model of hygro-thermo-chemo-mechanical behaviour of cement-based composites where the cement particles, activated by water, make the structure of cement paste matrix.
The diffusion factor of the hydrate layer for water is affected by the tortuosity of gel pore and the radius of gel pore in hydrate.
However, the composition of cement affect on the rate of hydration significantly because clinker minerals, such as alite (C3S, typically 65% of the total mass in the Portland cement), belite(C2S, 15%), aluminate (C3A, 7%), ferrite (C4AF, 8%), have their own reactions with water.
Since some aspects of such multi-component hydration process have not been cleared yet, all quantitative predictions contain some phenomenological factors, coming from macroscopic observations and measurements.

Surface braiding angle is a important index for affecting the 3d braided composites, usually, braided angle within 15°- 25°called small braiding angle, and the specimen with braided angle 20°are the most representative of small braiding angle specimens.
When the braiding angle is larger, the events are more and the acoustic emission waveforms are gentle, so the mechanical properties of materials are more unstable [6-10].
Due to the influence of various factors, the event counts of parameters analysis only rough record the activity of the source acoustic emission.
It is provided a good basis for mechanical properties of 3D braided composites and a good guarantee on acoustic emission sources in the research. 4.
Acoustic emission analysis of the flexural and tensile properties of 3-D braided composite materials[J].Journal of Textile Research.2007,28(4):52-55

The results will provide necessary reference for the further optimization design of condenser. 1 Introduction The application and development of the once-through boilers and nuclear power devices in the electricity industry lead to higher requirements for condenser performance [1].To analyze the stiffness and strength of large-scale condenser by using economic and efficient methods, it is particularly important to instruct condenser optimization design and to study the mechanical operation properties of the condenser components.
Similarly, air cooling zone of the tube sheets and air-cooled equivalent entity is also set bonded. 2.3 Mechanical properties of the tube sheets materials and condensing tubes As the tube sheet is a composite of different materials, we need to calculate its equivalent results.
These equivalent results of material mechanical properties in this paper are calculated according to relevant standards HEI.
Table2 Equivalent Mechanical performance parameters of tube sheets and tubes machinery performance equivalent elastic modulus[MPa] allowable stress Sm[MPa] perforated area 41147.12 50.23 unperforated area 189481.43 173 equivalent condensing tubes 5080 132.7 3 Results and analysis Stress and deformation are two main factors in finite element analysis.After calculation, the results of stress and deformation of condenser components are shown in Figure a~g, and the maximum equivalent stress and maximum deformation of components are shown in Tab. 3.
Mechanical Design( Higher Education Press, 2006)

Introduction Kevlar-Zirconia-Epoxy composites can be utilized in applications that need high-wear resistance due to their exceptional mechanical properties, low friction, and high durability.
Conclusion The wear mechanisms of composite coatings vary significantly under dry and lubricated conditions, influenced by operational factors like contact loads and rotational speeds.
Somashekar, “Role of Zirconia Filler on Mechanical Properties and Dry Sliding Wear Behavior of Glass/Basalt Hybrid Fabric Reinforced Epoxy Composites,” Applied Mechanics and Materials, vol. 895, pp. 200–205, Nov. 2019, doi: 10.4028/WWW.SCIENTIFIC.NET/AMM.895.200
Yi et al., “Improved tribological and thermo-mechanical properties of epoxy resin with micro-nano structured ZrO2/Ti3C2 particles,” J Appl Polym Sci, vol. 138, no. 41, p. 51209, Nov. 2021, doi: 10.1002/app.51209
Zeng, “Influence of graphene nanoplatelets on mechanical properties and adhesive wear performance of epoxy-based composites,” Friction, vol. 9, no. 4, pp. 856–875, Aug. 2021, doi: 10.1007/S40544-020-0453-5/METRICS.  

Modal Analysis of Vegetable Transplanter’s Mounting Headstock Based on ANSYS Junling Wang1,a , Xinxin Zhu 1,2,b , Zuli Zhang 1*,c and Yuqiu Song1,d 1College of Engineering, Shenyang Agricultural University, Shenyang, China, 110866 2 Shantui Construction Machinery Co.Ltd,Jining, China, 272073 ajunlingw@163.com, bzxx709382951@163.com,csauzhangzl@yahoo.com.cn dsongyuqiu@yahoo.com.cn * Corresponding author: sauzhangzl@yahoo.com.cn Key words: ANSYS；Mounting headstock；Modal simulation；Strength Abstract: Mounting headstock is an important part of the vegetable transplanting machine, its strength directly affects the machine's performance.
Introduction Mounting headstock is an important component of transplanter, its performance directly affects the performance and life of the transplanter.
The failure manner of mounting headstock is related to the mechanical properties of material, the type of load, stress, the shape and size of component member, temperature and environmental factors.
Modal analysis is a technology used to confirm the vibration characteristics of a structure, through which, the natural frequency, vibration mode and its participation factor, that is the participation extent in the vibration of a vibration mode in specific direction, can be obtained.
Finite Element Method of Mechanical Design [M].

Meanwhile, the key parameters affecting the evacuation can be analyzed with the application of fire simulation softwares, thus the conditions of ASET will also be made clear.
The Main Influencial Factors in the Evacuation On the whole, the factors affecting the evacuation include personnel density in the channel, the movement speed, human behavior and psychology in a fire, the familiarity with the building, the rationality of the construction structure and layout, the validity of evacuation signs and emergent lighting system, all of which will directly affect the time and the evacuation .
Therefore, per capita minimum space in the passageway has to be 0.28m2 in order to ensure the safety of evacuation Influence of personnel properties on evacuation Personnel properties include general characteristics and response features.
The former consists of such personal factors as the age, gender, physical health and social relations as well.
The space configuration properties are stored in geometry database for convenient use.

Introduction In daily life, due to a lot of reasons and factors lead to the mechanical equipment or parts failure.
With the development of the modern science and technology, the requirements of mechanical safety and reliable operation is more higher.Failure analysis on fracture can grasp the cause of the accident, so it is particularly important.
Due to the influence of the external environment, conversion device accuracy, noise interference and transmission information loss and so on, Failure image quality will be affected during the image acquisition process, then affect the late recognition and analysis.
Mathematical morphology pretreatment Due to the influence of external environment factors, fracture images in collected will under the influence.
It focuses on the collection of image structures, This structure can not only describe the macroscopic properties about the research object,but can also said its microscopic properties.

Samples were cured under hydrothermal conditions up to 170 °C for 24h and changes in mechanical properties, phase composition and porosity were monitored.
It was confirmed, that hydrothermal treatment can lead to acceleration of chemical reaction and promising mechanical properties.
It was confirmed, that concentration and type of alkaline activator and higher temperature and pressure are factors that have an influence on formation of crystalline phases [16].
The mechanical properties of the prepared samples were monitored.
Mechanical properties are affected by the change in phase composition, the formation of the aluminosilicates and the character and volume of pores associated with excess of water during hydrothermal treatment.