bluuebunny/crossref_metadata_2025 huggingface dataset:
Thermal Runaway of the BaCO3 + Fe2O3 Homogenous Mixture and Mechanical Alloys at the Microwave Heating
Authors: Savu I. Danut , Savu Sorin Vasile , Benga Gabriel Constantin
Published: November 2013

Microwave heating represents a modern technique to sintering the composites materials. The microwaves absorbance property of the materials is depending by the electrical permittivity of the materials. Researchers showed that the ceramic materials are suitable for sintering using microwave heating. The most important advantage of that sintering procedure is the reduced sintering time and temperatures. However, during the heating process these properties are changing and a pattern of the heating process cannot be established. The penetration depth of microwaves into materials depends on the electrical properties of them, and gives rise to a heat source. The electromagnetic wave absorption is responsible for the macro and micro structural changes in the materials morphology, and consequently for their electrical properties. Thermal runaway is one phenomenon which should be avoided during the microwave processing of the materials. The microwave heating consists in direct introduction of the energy in the volume of the material. If the absorbance properties of the material are increasing with temperature, than a critical phenomenon, called thermal runaway, appears during the heating process. This paper aims to study the thermal runaway of the BaCO3 + Fe2O3 homogenous mixture and mechanical alloy in a mono-mode applicator, when the heat source is a microwave generator at 2,45 Ghz. A special mono-mode chamber has been designed with dimensions 140 x 140 x 70 mm and an active system for rotating the samples, in order to record the values of the temperature and to assure a uniform exposure of the samples to the high frequency electromagnetic field. The materials used in experiments were homogenous mixture of BaCO3 + Fe2O3 which have been milled in a planetary ball mill for 5 and 20 hours. The experimental procedure consists in establishing the levels of the temperatures during the microwave heating process when the thermal runaway appears. These experiments have been done for fixed levels of microwave injected power from 0 1250 W. Numerical simulation for different heating conditions (microwave power, heating time, position of the samples inside the chamber) has been performed in order to elaborate a predictable mathematical model for continuous microwave heating and avoiding the thermal runaway of the homogenous mixture.
Fuzzy Logic Applications in Flanges Manufacturing
Authors: Turc Cristian Gheorghe , Belgiu George
Published: November 2013

The industrial engineering experts consider the product early design stage as one of the most important stage of the design process, because it influences all stages of the product life cycle. One of the capital questions for manufacturing or design engineering people is how simple or elaborated work piece to use for a given part, in a specific set of production conditions. The optimization problem consists of the choosing of the right work piece for the current production conditions. In many cases this problem is solved empirically, based on the experience of the manufacturer. This approach leads to results that are situated more or less close to the optimum for the technical and economical point of view. Fuzzy logic is a method that is used in system control and analysis design, because it shortens the time for engineering development and sometimes, in the case of highly complex systems, is the only way to solve the problem. For the parts manufacturing, the main idea of the algorithm is to formalize the knowledge regarding production volume, geometry, loading conditions and other factors, using fuzzy sets and then to take the work piece choosing decision through the inference rules that are specified to fuzzy logic methodology. The described fuzzy logic algorithm allows a rapid, argued choosing of the work piece type in the production. The paper describes the method implementation for the manufacturing of flanges, including the description of the software results.
Improved Model to Determine the Tool Life and the Cutting Speed for Minimum Cost at Drilling the Steel 10TiMoNiCr175
Authors: Vlase Aurelian , Blăjină Ovidiu , Darie Vlad
Published: November 2013

In the specialized literature the cost of the machining process has been analyzed using a number of approaches and varying degrees of simplification to determine the optimum tool life and the tool speed. The accuracy of prediction is dependent on the degree of sophistication of the model. The purpose of this paper is the optimization of the cutting tool life and the cutting speed at the drilling of the stainless steels in terms of the minimum machining cost. A more comprehensive nonlinear programming model to minimize the total cost at the drilling of a stainless steel is developed in this paper. The optimum tool life and the associated tool speed are obtained by solving this model. The results can be taken into consideration in the educational studies and in the theoretical technical research. They can be implemented in the manufacturing activity.
Research on Electromagnetic Properties of High Entropy Alloys
Authors: Florea Iulia , Florea Raluca Maria , Bălţătescu Oana , Soare Vasile , Roman Costel , Carcea Ioan
Published: November 2013

In 1995, Yeh suggested the formation of an alloy made up of at least five metallic elements which have large mixing entropy solutions with many elements forming solide alloys. This alloy appeared because traditional alloys are characteised by high fragility and are difficult to process. High entropy alloys are alloys which have approximately equal concentrations, formed by a group of 5 to 11 elements majority in composition, mole fraction of each major metallic element in the alloy is between 5% and 30%. During the research it has been proved that this alloy has a high hardness and it is also corrosion proof and also resistance and good thermal stability It should be mentioned that High Entropy Alloys are characterized as alloys consisting of roughly equal concentrations of at least five metallic elements and are claimed to favor close-packed, disordered structures due to high configurational entropy. Such crystal structures, e.g. face-centered cubic (FCC), are advantageous in that they should offer multiple active slip systems usually observed in ductile metals and alloys. This opens the door to a large number of rich chemistries which would otherwise contain unacceptable volume fractions of intermetallic compounds to be useful in structural applications That way in this paper will carry out research to one specific high entropy alloy, we analyze the physical, chemical, electrical, magnetic, corrosion resistance of these materials, heat treatments corresponding and plastic deformation. This paper is divided into several chapters which will present application domains, and also a number of conclusions. Key words : high entropy alloys, properties of alloys, application domains, corrosion proof, thermal stability
Optimum Tool Life and Cutting Speed for the Maximum Productivity at the Drilling of the Steel X6CrNiTi18-10
Authors: Blăjină Ovidiu , Vlase Aurelian , Darie Vlad
Published: November 2013

The research in the last decade regarding their cutting machinability have highlighted the insufficiency of the data for establishing of the optimum cutting processing conditions and the optimum cutting regime. The purpose of this paper is the optimization of the tool life and the cutting speed at the drilling of the stainless steels in terms of the maximum productivity. A nonlinear programming model to maximize the productivity at the drilling of a stainless steel is developed in this paper. The optimum cutting tool life and the associated cutting tool speed are obtained by solving the proposed mathematical model. The use of this productivity model allows greater accuracy in the prediction of the productivity for the drilling of a certain stainless steel and getting the optimum tool life and the optimum cutting speed for the maximum productivity. The obtained results can be used in production activity, in order to increase the productivity of the stainless steels machining. Finally the paper suggests new research directions for the specialists interested in this field.
Mechanical Properties of Fibre-Metal Composites Connected by Means of Bolt Joints
Authors: Zolkiewski Sławomir
Published: November 2013

The fibre-metal laminates made of a steel plate and fibreglass laminate plate were tested in the special laboratory stands. Epoxy resin and polyester resin were used as matrix to fabricate the composites. The fibre-metal laminates combine advantages of metals and laminates. These materials have very good force versus displacement characteristics and overall mechanical properties. They are very popular and widely applied in technical systems. They can be put to use in connecting materials made of various fabrics, connecting high number layer laminates and most of all connecting metals and laminates. In this paper there are the results of testing fibrous composite materials connected in bolt joints presented. Composite materials reinforced with fiberglass, carbon and aramid fibers are considered. The impact of number of applied bolts in a joint on strength properties was investigated. The connections by means of eight or sixteen bolts were compared. A major problem of modelling the composites is assuming physical and material parameters of the analyzed elements.
Design and Manufacturing Preparation of a Patient Specific Acetabular Cage
Authors: Costin Serban , Micu Constantin Anton
Published: November 2013

Total hip arthoplasty or hip replacement is today a common and highly successful a surgical procedure. However, in the revision artoplasty the procedure is more complicated, as standard devices have to be adapted to different shapes of acetabular defects, which are patient specific especially when they are bigger and wider spread. This kind of big defects, sever acetabular defects, pelvic discontinuity, defects resulted from tumor problems, protrusion, can usually be addressed with a standard Burch-Schneider Antiprotrusio Cage or a Mueller Ring in order to restore the mechanics and the true center of the hip. This paper proposes a design process and manufacturing preparation for a patient specific acetabular cage. The design is intended to fix problems that standard cages sometimes do not resolve, for example insufficient fixation due to the fact that the inferior flange did not engage the ischium, problems of bone graft resorption and in the same time tries to remain an affordable solution. The design process uses as input information the 3D reconstruction of the patient hip from CT scan. Important parameters like the position of the true center of rotation, acetabular anteversion and inclination are determined and calculated. Other parameters, such as number of fixing screws and their designated holes or the amount of bone to be covered with the custom acetabular cage (fixation surface), are proposed by orthopaedic specialist. The design methodology relays on commercial software, such as Solid Works for CAD, 3D Doctor for 3D bone reconstruction from the CT scans or other software for different file transformations. The model was optimized to be produced through direct metal laser-sintering (DMLS). Regarding the results, the particular implant was designed and optimized for fabrication and it is available to be produced. During the design process, although a systematized process was undertaken and implemented, some activities could not be done in systematic, repeatable way. Nevertheless, a design process strategy was established, so that the design would match the requirements of such implant and also a requirements list for the type and form of information needed for this kind of design. Also, we concluded that using software to automate some of the operations that were done manually by the operator would help decrees the design time and improve the repeatability of the process.
3D Conductive Textile Shields
Authors: Donciu Codrin
Published: November 2013

The perturbing presence of electromagnetic fields is responsible for numerous malfunctions in equipments operation. To eliminate these disturbances it is necessary both to reduce the electromagnetic radiation of electronic devices and to immunize them from the fields present in their operating environment. These requirements can be achieved by efficient shielding the source of the electromagnetic field and the receiver. The paper aims to develop new textile shield with spatial architecture, high shielding effectiveness, low manufacturing costs, shape diversity, mechanical elasticity and facile mounting. The shield were made by knitting and have a 3D spatial structure, with two external layers and an internal connection layer made with different combinations of conductive and non-conductive fibres.
Geometric Analysis of Motions Exercised by the Stewart Platform
Authors: Dymarek Andrzej , Dzitkowski Tomasz , Herbuś Krzysztof , Kost Gabriel , Ociepka Piotr
Published: November 2013

The study outlines the geometric analysis of motions executed by the Stewart platform and operated in the environment of a simulator for driving learning to be used by disabled people. The analysis was carried out on the basis of results obtained from the resolved kinematic problem for the inversed platform.
Virtual Analysis of the Mining Support under Loads of the Roof
Authors: Gwiazda Aleksander
Published: November 2013

The paper presents the results of virtual analysis of the stability of mining roof supports loaded by the roof rocks. The hydraulic roof support generally accounts for over 50% of the total value of a coal mining and excavating system. Many reports show that in some conditions roof supports behave differently than foreseen. To explain this phenomena the investigations basing on the virtual model were done [1,2]. This phenomena is very dangerous for miners because this behaviour of a mining roof support may cause dangerous accidents in coal mines. In the investigation process some questions have been asked. Firstly what type of a mining support is more liable to this behaviour. Secondly what work conditions are the most dangerous. To analyse this phenomena it was used models of two types of a mining support. One with two props and one with four ones. Results show that that the problem of plunged of roof parts of a support in the coal bed is consider with the construction of the support. The most dangerous is the roof support with two props. The consequences of this results are the recommendations to use rather supports with four props then two.
An Overview on the Design of Mobile Robots with Hybrid Locomotion
Authors: Conduraru (Slătineanu) Alina , Doroftei Ioan , Conduraru Ionel
Published: November 2013

In recent decades a considerable number of mobile robots with different locomotion systems have been developed. This paper is an overview on the designs of mobile robots with hybrid locomotion. Some solutions of hybrid locomotion mechanisms and control methods are presented. Most of the robots included in this category are using wheel-leg mechanisms as locomotion systems. In this way, the efficiency of the leg for moving in rough terrain is combined with the design simplicity and the low energy consumption of the wheel, when the robot is moving on structured environment.
Orthopaedic Prosthetic Systems Topographically Characterized at Nanometric Scale
Authors: Badita Liliana Laura , Gheorghe Gheorghe Ion
Published: November 2013

The main purpose of this project was to study and improve the tribological characteristics of hip and knee prostheses in order to use them for a longer period of time. We conducted a thorough investigation of components of hip and knee prostheses. We started with the study of hip prostheses obtained after revision surgery. In this paper we present some experimental results about the scratch resistance of Ti6Al4V alloy and Co-Cr alloy femoral heads coated by physical vapor deposition (PVD) with TiN and Co-Cr-Mo, respectively. Visual analysis and optical microscopy analysis of prosthetic components revealed numerous multi-directional scratches, deeper or less deep, frosted the surface in the geometric place of action of the resultant force application point, microcorossion and peeling of the coating on the prosthetic femoral heads made of CoCr coated with CoCrMo by PVD method. Scratches, corrosion, peeling and bio-tribo-corrosion of titanium nitride (TiN) coating from the Ti6Al4V femoral heads surface were also observed. Using atomic force microscopy (AFM), topographic characterization at nanometric scale of these surfaces was realized. Surface topography parameters such as minimum and maximum height, average roughness, and surface asymmetry were derived. It resulted that under the deposition there is a more veiled area. Roughness was used as an indicator of damage to the femoral head to obtain information on the variation in height from one point to another. AFM analysis revealed a dramatic increase in average roughness (Ra) of femoral heads compared to the maximum value of 0.05 μm provided under ISO 7206-2. From all these studies it was noted the need for a resistant prostheses, with anticorrosive composition and high mechanical properties. Among the numerous methods to reduce wear we realized thin films (biocompatible nanomaterials) deposition of TiN on 316L SS steel substrates by pulsed laser deposition method (PLD), to improve overall performance and, in particular, mechanical prosthesis of hip prostheses structures. The results obtained leads to the conclusion that PLD technique is a good method to make amorphous and crystalline films, dense and porous by controlling the laser system conditions. All parameters can be controlled and varied to identify the optimum structures and to obtain thin layers.
A Study Initiated because of the Global Warming from R-134a
Authors: Memet Feiza , Mitu Daniela Elena
Published: November 2013

Vapour compression cycles are commonly used in household refrigerators and also in many commercial and industrial refrigeration systems. R-134a is a working fluid widespread in this kind of systems. A chlorine free refrigerant such as R-134a has a disadvantage in the sense of its relatively high Global Warming Potential (GWP), although the specific Ozone Depletion Potential (ODP) is null. International concern over the relatively high global warming potential of R-134a, and other refrigerants belonging to the same family, will lead in the near future to the stop of their production and use. For this reason, the interest in finding of an environmental more benign substitute for this refrigerant is growing. In the meantime, the alternatives for R-134a should be as thermodynamically attractive as this chemical. In this study it is theoretically assessed the opportunity of using R-600a (isobutane) in the future environment friendly vapour compression refrigeration systems. Choosing of isobutane is explained by the fact that it is a naturally occurring refrigerant. During the thermodynamic analysis, R-134a and R-600a are evaluated for a range of evaporating temperatures starting with 25°C and finishing with 0°C. There are considered three levels of the condensing temperature: 30°C, 40°C, 50°C. For these two refrigerants are compared results regarding saturated vapour pressure, Coefficient of Performance, volumetric cooling capacity, compressor discharge temperature, refrigerant mass flow rate. Also, in the scope of future improvement of systems adopting R-600a as a refrigerant, it is performed an exergy analysis, which is able to reveal the hierarchy of inefficiencies in the system. The results obtained indicate that adopting of R-600a instead of R-134a in vapour compression refrigeration systems is a decision motivated not only by environment reasons, but also by thermodynamic arguments. Values for the Coefficient of Performance when using R-600a are slightly lower than when in use is R-134a, but isobutane offers better environmental requirements like zero Ozone Depletion Potential and very low Global Warming Potential. Exergy analysis developed for R-600a as a working fluid revealed that the most inefficient is the compressor. Better exergy efficiency can be obtained for higher values of the evaporating temperature.
Numerical Simulation Analysis of Temperature Field on Tympanites Roadbed
Authors: Yuan Jian Yi , Wang Chun Feng , Cheng Jian Hua , Zhang Ding Bang , Wu Zhen Hua
Published: November 2013

The physical model and calculating model of temperature field are founded according to the founded controlling equation. By simulating the changing progress of climate features, the temperature field of roadbed in permafrost region in different season was obtained. And some results are got by analyzing the diversity of temperature of key points. The last, the technology assumption of effectively controlling tympanites which combines replacing part frozen soil and resisting highway tympanites structure is brought up.
Aeolian Geomorphology Resources and Projects Development Suggestion in the Badain Jaran Desert
Authors: Fan Xiao Lu , Tian Ming Zhong , Liu Si Wen
Published: November 2013

Badain Jaran Desert is the third largest desert of China. The research on aeolian geomorphology resources will be beneficial to the sustainable development of tourist industry and environment in the Badain Jaran Desert. This paper uses these basic geographical data, such as ETM+, 1:50,000 topographic map, GDEM, Google Earth data and so on. Then we integrate geological surveys in the field and summarize the characteristics of aeolian geomorphology resources. By combining with tourism projects of aeolian geomorphology resources set in other scenic area, the tourism development projects of aeolian geomorphology resources and desert environment in the study are put forward with the purpose of offering practical advice for tourism development of aeolian geomorphology resources and the control and utilization of desert environment in the Badain Jaran Desert.
On Paleotectonic Stress Level Estimation of Geological Model
Authors: Zhang Chen , Huang Hao , Wang Ning , Cheng Sui Han
Published: November 2013

How to determine the stress level of the boundary conditions of the model is a key issue in the study of geological structure and paleostress field, which is of great significance for geological structure research. The paper takes Chengzhuang coal area in Jincheng of Shanxi Province as an example to analyze its geological structure model and study the method to determine the paleotectonic stress level so as to make a contribution to study of establishing regional tectonic models.
Stability Analysis of Highway Tunnel through Mined-Out Area during Excavation Process
Authors: Yang Zhi Hao , Cui Ge , Fu Ya Peng , Fang Yong , Yang Bin
Published: November 2013

Tianpingzhai Tunnel on Dazhou-Wanzhou Expressway passes through the mined-out area, the spatial position of the goaf changes constantly comparing to the tunnel during excavation, and broken rock mass of the caving zone is most likely to collapse, which affects construction safety in return. Two dimensional computation models were built by using finite differential software FLAC to simulate excavation process when the coal-mined area is right above or below the tunnel. In 2D models, goaf strata were regarded as horizontal, and buried depth and coal thickness were limited to 300 meters and 0.5 meter respectively. The displacement around the tunnel, forces of primary lining, axial force of bolts and plastic zone of surrounding rock have been analyzed under these circumstances that the distances between tunnel and goaf are 1m, 6m and 12m. According to the results, when the distance between goaf and tunnel is less than 12 meters,underlying goaf has greater impact on the displacement around the tunnel and average axial force of bolts than overlying goaf, as well as the size of plastic zone of surrounding rock. Its strongly suggested to avoid underlying goaf if the tunnel have to pass through the mined-out area.
The Research on the Influence Law on Thermal Resistance of Borehole
Authors: Qi Zi Shu , Gao Qing , Liu Yan , Bai Li
Published: November 2013

GSHP are of strategic and necessary part for the efficient utilization of renewable energy and energy conservation. Vertical ground heat exchanger system is one form of GSHP and it is a way to solve the problem of the imbalance between cooling load and heating load except for some extreme hot or cold climate areas. In the paper, the study of underground heat exchanger heat transfer mode, and the influence law of the borehole diameter, shank spacing, and grout conductivities on thermal resistance of borehole are discussed systematically.
Design of FPB about Bridge in High-Intensity Earthquake Area
Authors: Xia Jun Yong , Kong Ling Jun , Leng Xin Yun
Published: November 2013

In this paper, a seismic isolation scheme by FPB about bridge in high-intensity earthquake area is introduced. Typical methods and calculation examples of using dynamic time-history analysis in this scheme as well as the process and methods of parameter determination and design verification of FPB are put forward. All these methods play guiding roles in the seismic isolation design of bridges and the design and application of FPBs.
Computational Research on Seismic Intensity Based on Ground Motion Parameters
Authors: Li Wei , Li Shan You , Li Liang , Han Jing Long
Published: November 2013

After an earthquake event, the spatial distribution of seismic intensity of the event and extremely destructed area could be quickly evaluated by means of the empirical relationship between ground-motion parameters and seismic intensity, which has been proposed for years. This can provide a basis for the government to carry out emergency relief and reasonable distribution of relief supplies. In this paper, the computational methods of instrumental seismic intensity used at home and abroad are briefly introduced. By analyzing the advantages of the methods in the USA and Japan, a relatively simple computational method of seismic intensity is proposed. Firstly, the acceleration time history (Aall) and velocity time history (Vall) of the complete vibration are synthetized by the filtered three-direction acceleration and velocity time histories, and substituted in the empirical formulation. Then, the seismic intensity can be computed by the sorting method. After that, this method is compared with the intensity scale evaluation method and fuzzy algorithm by using the strong motion parameters of Wenchuan earthquake. The results show that the method proposed in this paper is better than the two methods and has certain practical values.
Seepage Analysis of Plane Finite Element on Clay Core Dam of Laojunshan
Authors: Zhang Hong Hai , Wang Chun Yan , Gong Ai Min
Published: November 2013

Through calculation of the seepage finite element, the result shows that the anti-seepage effect of clay core and grouting curtain is obvious. The phreatic line of dam conforms to the general law, and seepage stability of the dam meets the requirements. The sensitivity analysis of the different curtain depth indicate that there is a inflexion on the relation curve of seepage discharge and curtain depth, and to deepen continually the curtain have less effect on the dam seepage discharge when the curtain more than 50m.
Two-Phase Flow Model Applied in the Oxidation Ditch
Authors: Chen Lin , Feng Qian
Published: November 2013

The unique hydraulic characteristics in oxidation ditch have a close relation with the quality of treated water, the design and optimization of the oxidation ditch. The experimentally validated numerical tools, based on computational fluid dynamics(CFD), were proposed. Sewage- sludge two-phase model and liquid-gas two-phase model of an oxidation ditch were built through CFD numerical method. Meanwhile, a velocity field measurement was enforced on the ditch by Acoustic Doppler Velocimeter(ADV). The simulated results and experimental data were in good correspondence, which verify the simulation methods are reasonable and the simulation results are acceptable. The combination of simulation and experimrntal measurement has profound influence on the hydraulic optimization of oxidation ditch. 3D simulation could be a good supplement for improving the hydrodynamic performance in oxidation ditch designs.
The Application of Vapour Equlibrium Technique in Water Retention Study of Fine Grained Tailings
Authors: Jiang Qing Hua , Yu Chen Xiang
Published: November 2013

As a problematic material, fine grained tailings have many particular engineering characteristics and seriously affect the safety and stability of the tailing dam body. These engineering properties are closely related to moisture migration and soil suction under different water content. This article chose fine grained tailings of Li Tie Lan Ting tailings dam in Zhejiang province as an example, and measured the soil water characteristic curve (SWCC) of fine grained tailings with different partical size composition and dry density using vapour equilibrium technique. Efforts have also been made to demonstrate the influences of soil type, dry density on water retention. The study result shows that particle-size composition has a significant impact on SWCCs of the tailings. Finer grained samples have lower water loss rate and higher water-holding capacity than coarse grained samples in the same suction state. Contrary with low suction stage, dry density has negligible influence on the soil suction, and parameters effect SWCCs at high suction stage. The research results may provide a theoretical support and a beneficial reference for further research of fine grained tailingss engineering properties.
Influence of the Roughness of Different Materials of Plastic and Metal Pipes on the Pressure Variation in Hydraulic Curves
Authors: das Graças Braga da Silva Fernando , Deice Ivan Felipe , Mambeli Barros Regina , Tiago Filho Geraldo Lúcio
Published: November 2013

A hydraulic simulation in pipes allows us to analyze the hydraulic behavior under various conditions. Hydraulic experiments are essential because there are many peculiarities in the analysis of the experimental processes. Computational fluid dynamics (CFD) tools assist in this process, they allow analyzes are made under the most varied conditions. Another parameter that typically affects the behavior of hydraulic fluid under pressure is the roughness of the materials that make up the pipes. In this work, we studied the variation of pressure in water pipes made from many common materials, such as plastic, cast iron and steel. Experimental data were used for validation, and the results showed variation in the parameters of the pressure and velocity fields.
Application of Loose Blasting in Fully-Mechanized Coal Face Crossing Faults
Authors: Li Wei , Yang Ren Shu
Published: November 2013

Loose blasting technology is applied to the problem of fully mechanized coal face passing through fault. The paper gets safe and practical loose blasting parameters and blasting process, achieves no re-open-off cut for the fully mechanized coal face, reduces loss of coal pillars for faults and improves the coal recovery rate. At last, the goal of high yield, steady yield, and increasing yield for fully mechanized mining face is realized.
Synthesis and Performance Study of 5, 5 '- Diaryl - 2, 2' Bi (1,3,4-oxadiazoles )
Authors: Zhang Xiong Lu , Qian Yi Ping
Published: November 2013

1,3,4-oxadiazole (OXD) and its derivatives have excellent thermal stability and oxidation resistance and strong blue fluorescence emission [.Six novel compounds have been designed and synthesized And their structures were confirmed by 1HNMR,FT-IR,MS, UV-vis absorption results showed that the maximum absorption wavelength appeared at 430nm,and fluorescence spectroscopy results showed that emit strong purple fluorescence in DMF solution.
Measurement Error Analysis of Heat Coefficient in Solar Assisted Heat Pump System
Authors: Zhang Xi Ming , Wang Yan
Published: November 2013

Solar energy is the main source of all energy on earth .The earth obtain the total energy annually is ten thousand times of the earth energy consumption at present, but the solar energy has a lower energy density on the earth's surface. If we want to use the solar energy, it is necessary to solve the intermittent and reliability problems of solar energy. The paper presents the principal of error analysis and deduces a formula of measurement error for heat coefficient in solar assisted heat pump system. We analyses the influence of water temperature, water flow and electrical energy consumption on measurement error of heat coefficient in the system. The result stresses that the key factor of reducing the measurement error is water temperature measurement of the system.
The Applications of Dynamic Grouting Technology in Ultra-Deep Shaft Wall
Authors: Zhang Bin , Pan Yong Chao , Qin Qing Xin
Published: November 2013

With the growth of the national economy, the social demand for coal resources is increasing. In order to maintain the sustainable development of the national economy, we must develop the deeper and wider coal layers. In deep mine construction and in the process of extending shaft downwards, we often encountered with soft rock zones and rock fracture zones where were often subjected to floods. Grouting technology is one of the most effective and reliable method to deal with water in the mine. But the traditional grouting method could not reach the good effect in plugging water. According to the local engineering practices and experiences, the new method we have mentioned above takes better effect in dealing with the problem of water permeation in ventilating shaft of Niaoshan coal mine.
Development of Perpendicular Sensor for Disaster Prevention
Authors: Yang Mo , Warnajith Nalin , Minato Atsushi , Ozawa Satoru
Published: November 2013

Monitoring of inclination of land is important to prevent damage from landslide. Low cost and stable system is necessary for this purpose. This paper presents a new inclination measurement system and its application to sensor network of disaster prevention. Our system has a bull's eye level, a digital camera and wireless module. The angle and direction of inclination is measured from the photo of bull's eye level. The achieved resolution was 0.0053degree/pixel using a bull's eye level with a curvature radius of 800 mm. Measurement data was compared with the data from commercial inclinometer.
Evaluation of the T-Stress and the Higher Order Terms of the Elastic Crack Based on the SBFEM
Authors: Liu Jun Yu , Xu Feng Lin , Ning Bao Kuan , Fan He
Published: November 2013

The Scaled Boundary Finite Element Method (abbr. SBFEM) developed by Wolf and Song is a numerical method which has a half analytical nature. In the paper, the asymptotic fields of central crack tip and single edge crack tip of the plane elastic plates are evaluated based on the SBFEM. Numerical examples are provided to demonstrate its high accuracy and effectiveness, and the numerical results show that SBFEM can calculate the SIFs, T-stress and the coefficients of higher order terms with higher efficiency and accuracy. The singular fields of crack-tip with complex configuration can be evaluated combining the sub-structuring technique (or super-element).
The Performance Research of TiO2 Electrode Prepared with Ionic Liquid and Ultrasonic Resonance
Authors: Liu Yi Lu , Yang Jie , Song Dong Dong
Published: November 2013

With the medium of triethanolamine acetate ionic liquids and the help of cavitation effect of ultrasonic resonance, the TiO2 collosol is prepared by the sol-gel method and being loaded on nickel foam. The TiO2 electrodes are formed by calcinating at the high temperature. The results show that the optimal electrodes can be obtained with the medium of triethanolamine acetate ionic liquids, under the condition of high power ultrasound resonance for 15 minutes, the ionic liquid volume of 3 mL and the calcination temperature of 400 °C. After the wastewater is processed by photoelectric catalysis under the conditions of electrolysis voltage of 12V, electrode spacing of 1 cm, wastewater pH of 4 and illumination time of 90 minutes, the COD removal rate can reach 63.5%, while the decolorization rate can reach 93.6%.
Synthesis of pH-Responsive Copolymer PVA/PDEAEMA by ATRP
Authors: Jiang Ping , Li Du Xin , Liu Yue Jun
Published: November 2013

In this paper, the macroinitiator (PVAc-Cl) was prepared from vinyl acetate telomerization reaction by using BPO as initiator and CCl4 or CHCl3 as chain transfer agent. Then the pH-responsive PVAc /poly (2-(dimethylamino) ethyl methacrylate) (PVAc/PDEAEMA) were synthesized via atom transfer radical polymerization (ATRP) and evidenced by FTIR spectroscopy. PVA/PDEAEMA were synthesized by alcoholysis PVAc/PDEAEMA and evidenced by FTIR spectroscopy.
Performance and Hydration of Blended Cements with Fly Ash and Sugar Filter Mud
Authors: Qian Chao , Gao Wen Yuan , Luo Chun Yuan , Liu Gui Shan , Hao Hong Shun , Hu Zhi Qiang
Published: November 2013

Thermal insulation material with flexural strength 0.597 MPa, compressive strength 1.1111 MPa and porosity 46.71% shows that its density of the materials decreases down to 0.5466 g/cm3 using sugar filter mud as raw material. The closed porosity and dense structure of sample has been observed by photograph and the main crystalline phases of the sample using XRD techniques are tricalcium silicate and ettringite. These mineral reacting with water will occur the hydration reaction and is contribute to improve the strength of the body.
Arc Routing Using a Geographic Information System: Application in Recyclable Materials Selective Collection
Authors: Oliveira Raquel L. , Lima Renato S. , Lima Josiane P.
Published: November 2013

This study aims to utilize a Geographic Information System (GIS) as an arc routing tool (door-to-door model) for a recyclable materials selective collection program. The investigation uses real data from material gatherers association in the city of Itajubá, Minas Gerais, Brazil. The research method is modeling and simulation. TransCAD 4.8 is used because it possesses an arc routing routine. Scenarios were simulated in which the most efficient routes were sought (shortest and fastest) in comparison with the associations real trajectories, which were collected in the field of study by means of a Global Positioning System (GPS) device. The results obtained, when compared to the current system, showed better performance (distance, time and volume of material). Thus, by using a GIS, it can be said the main logistics problems in the gatherers association are direct consequences of poor structuring.
Noise Exposure among Machine Operators on Construction Sites in South Johor, Malaysia
Authors: Zaiton Haron , Abidin Mardhiah Z. , Lim Ming Han , Yahya Khairulzan , Jahya Z , Mohd Said Kamilah , Saim A. Aziz
Published: November 2013

Machines operators expose to excessive noise in the workplace that may lead to hearing damage. This study investigates construction machine operators noise exposure levels for eight hours or time weighting averages (TWAs), relationship TWA with machine noise emission level, the practices of using hearing protection devices (HPDs) and working in a closed machine cab. Heavy and non-heavy machine operators at five construction sites involved with excavation and piling activities were selected and measured by using dosimeters. 68% of operators were exposed to TWA of 85 dBA and 18% of the operators exceeded the permissible limit. 40% of operators work inside a closed machine cab, 18% wear earplugs and only 16% practiced both. Both operators of heavy machines (except excavators) and dump trucks are exposed to TWA > 90 dBA if they work in open machine cabs. The TWAs were found well correlated (r=0.41) with the machine noise emission, which ranged between 84 dBA to 125 dBA. Furthermore, this study proposes the type of HPD for the operators of typical machine to minimise the risk of hearing loss.
The Application of Genetic Algorithm Backpropagation Neural Network Model on the Prediction and Optimization of Wastewater Treatment System
Authors: Jia Fu Quan , He Zhang Wei , Tian Zhu Jun , Chen Zhao Bo , Wang Hong Cheng , Chen Yi Meng , Jiang Bao Jun
Published: November 2013

Prediction and optimization on water quality parameters (WQPs) have become more and more important to the wastewater treatment system (WWTs). In this study, the genetic algorithm backpropagation neural network model (GA-BPNN) had been used to predict and optimize WQPs of a low-strengthen complex wastewater treatment system (LSCWWTs). Results showed that the correlation coefficients between the predicted values and measured values were R2 =0.946 for COD, R2=0.962 for BOD, R2=0.933 for TN, R2=0.985 for NH3-N, R2=0.969 for TP, and R2=0.968 for SS, indicating the predictive values by the GA-BPNN model well fitted the mesured values of effluent WQPs. The optimal effluent WQPs were COD=27.6mg/L, BOD=7.1mg/L, TN=5.4mg/L, NH3-N=0.9mg/L, TP=0.11mg/L and SS=9.25mg/L, respectively. And the corresponding operating parameters were MLSS=3045.4mg/L, MLVSS=2405.9mg/L, T=23.2 °C, R=1.4, SRT=12.5d, HRT=17.3h, CODin =643.3mg/L, BODin=342.2mg/L, TNin=54.2mg/L, NH3-Nin=45.3mg/L, TPin=4.9mg/L, SSin=452.6mg/L, which could be beneficial to the operation optimization of LSCWWTs.
Determination of Chlorobenzenes in Wastewater by Single-Drop Microextraction Coupled to Capillary Gas Chromatography
Authors: Sun Jian Qi , Qiao Bo , Dai Jun
Published: November 2013

This study describes an analytical method employing capillary gas chromatography (GC) using flame ionization detection (FID) that has been developed for the simultaneous determination of chlorobenzenes (m-dichlorobenzene (m-DCB),p-dichlorobenzene (p-DCB),o-dichlorobenzene (o-DCB) and 1,2,4-trichlorobenzene (1,2,4-TCB)) in wastewater. For this purpose, single-drop microextraction (SDME) was applied as a sample preparation technique. The SDME parameters such as types of extractants, volume of the microdroplet size, extraction time, stir rate and immersion depth of needle point were studyed and optimized. The method was linear in the ranges from 4.0×10-3to 40.0 μg·mL-1form-DCB,p-DCB ando-DCB, and 4.0×10-3to 30.0 μg·mL-1for 1,2,4-TCB withR2≥0.9955. The SDME procedure allowed efficient recovery of the investigated chlorobenzenes ranging between 80 % and 105 % with a relative standard deviation (RSD) ≤6.5 for actual wastewater sampes spiked with 2, 5 and 10 μg·mL-1of chlorobenzes, respectively. These results showed the potential of this technique for chlorobenzenes monitoring in wastewater samples. Furthermore, the investigated methods are simple, reliable, reproducible, and not expensive.
Interprovincial Space Effect Analysis of China's Atmospheric Environment Quality
Authors: Dong Ke
Published: November 2013

Through an analysis about the atmospheric environment SO2space effect of China from 2000 to 2011, this article puts forward that the atmospheric pollution in China is influenced by per capital GDP and industrial structure to a large extent. Meanwhile, environmental efficiency factors which should restrict atmospheric environmental pollution have positive spillover effect to environmental pollution to surrounding area, which indicates that the environmental pollution treatment in China in current stage is only transition of the pollution in a disguised form. In some regions, industries are moved to less developed areas around in order to enhance their environmental compliance, so polluting industries cannot be moved out like those in developed regions and the environment is difficult to improve.
Discussions on Fog and Haze Weather Treatment from Planning View — Taking Jinan as Example
Authors: Han Yue Zhen , Kong Min , Cao San Peng
Published: November 2013

Currently fog and haze weather has become a new kind of meteorological and environmental disaster phenomenon. Taking jinan city as an example, this paper analyzed the causes from planning view.One is the absence of traffic environmental bearing capacity in traffic planning;The second is the lack of sufficient attention to ventilation channel planning;The third is unreasonable layout of industrial land. In order to solve these problems, one hand, we should put forward some city planning countermeasures, such as developing public transit system and paying more attention to bicycle lane and sidewalk planning. On the other hand, it is evitable that automobile possession will increase with economy development, so we should pay more attention on roadway and river course ventilation planning, they are helpful for contaminant spreading by forming an atmosphere favorable to emission diffusion. Moreover industrial land should be laid in upstream of minimum wind frequency and downstream of maximum wind frequency. By these means the fog and haze weather can be controlled to some extent.
Greenhouse Gas Emission Factor of Scrapped Cable and Wire Recycling Factories
Authors: Chang Pu , Lu Mei Fang , Lin Jim Jui Min
Published: November 2013

Carbon footprint of three scrapped cable and wire recycling processing plants was analyzed by examining the annual carbon emission and trend for 2009-2011. Among the six greenhouse gases (CO2, CH4, N2O, SF6, HFCs, and PFCs), the annual emission of CO2 was the highest (>95%), while remaining gases only accounted for less than 5% of the total greenhouse gas emission. When analyzing the collected data based on different frontier categories, Category II (greenhouse gas emission indirect caused by electricity consumption) had the highest emission proportion (>57%). It is because the machines used for the physic-mechanical processing procedure require a lot of electricity. In order to do emission inventory accurately and control the electricity consumption, laws or regulations should stimulate electricity consumption to be recorded and monitored separately for each operation permit. It is also recommended to record and monitor electricity consumption of administration area and the manufacturing/processing area separately. Results of this study revealed that the average emission factor for processing recycled cables and wires using a physic-mechanical method was 0.0474±0.0162 tonnes of CO2e per tonne of material processed. If the calculation was based on the amount of products generated, the EF of average greenhouse gases was 0.1613±0.0589 tonnes of CO2e per tonne of plastics, 0.0766±0.0278 tonnes of CO2e per tonne of copper, 1.7891±1.4572 tonnes of CO2e per tonne of aluminum, and 2.1030±1.6937 tonnes of CO2e per tonne of iron.
Investigation on the Relationship between Space Form and Behaviors Tracks in the Commercial and Cultural Blocks - Two Cases Study in Hefei Jindadi 1912 and Nanjing 1912
Authors: Li Jin , Li Zao , Zeng Jun
Published: November 2013

This paper chose two commercial and cultural blocks as the study objects to do walking experiments with GPS, namely Hefei Jindadi 1912 and Nanjing 1912 ,and collected 134 groups of behavior tracks information. The analysis on the two blocks space with typology method could compare and analyze the different characteristics of the four kind space forms. And author counted the data for the tourist behavior scope and walking distance to summer up the better characteristics of high utilization rate of nodes. The walking experiments with GPS put forward improvement suggestions for the existing space in the design of commercial and cultural blocks to make humanized atmosphere for the commercial and cultural blocks.