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Online since: October 2025
Authors: K. J. Osinubi, Adrian O. Eberemu, Paul Yohanna, R. K. Etim, T. S. Ijimdiya
incubation.
2.1.3 Cementation Mixtures
A composition of 10 g NH4Cl, 3 g nutrient broth, 2.12 g NaHCO3, 2.80 g CaCl2 in addition 20 g urea, per liter of distilled water, was used as cementation reagent for the study.
2.1.4 Chemical Structure of Laboratory Simulated Leachate
The chemical composition of laboratory simulated leachate is made up of table salt as well as monosodium glutamate gotten from normal crops, added to the municipal solid waste soaked in water.
2.2 Methods
2.2.1 Isolation process of Bacillus coagulans Species
The processes involved in the isolation of the microbial species from the soil known as the serial dilution [19].
2.2.2 Microbial Culturing Media and Growth Environments
The processes and methods adopted for preparing the culture media as well as the growth conditions are based on the recommendations of Stocks-Fischer et al. [20].
2.2.3 Hydraulic Conductivity Measurement
Falling head approach was used for the test since the soil sample used is a fine-grained
Results and Discussion 3.1 Index Properties Results of study on the soil materials show that it is fine-grained with 11.3% as the value of its moisture content in the natural form.
However, considering soil samples permeated with leachate as permeating fluid, micrograph depicts a coarse grain appearance with cemented surface morphology.
Francisca and Glatstein [29] described the existence of microbes in leachate reduced meaningfully in magnitude for hydraulic conductivity samples subjected to a long duration of time, measured by right observing the number of the existing microbes in the permeating liquid.
Results and Discussion 3.1 Index Properties Results of study on the soil materials show that it is fine-grained with 11.3% as the value of its moisture content in the natural form.
However, considering soil samples permeated with leachate as permeating fluid, micrograph depicts a coarse grain appearance with cemented surface morphology.
Francisca and Glatstein [29] described the existence of microbes in leachate reduced meaningfully in magnitude for hydraulic conductivity samples subjected to a long duration of time, measured by right observing the number of the existing microbes in the permeating liquid.
Online since: August 2011
Authors: Da Hu Zhu, Zhen Xin Zhou, Bei Zhi Li, Qiang Zhang, Yi Chu Yuan
Elastic deformation
of grain
Elastic deformation
Pile-up
Removed
(a) Three phases of surface grinding (b) Five phases of cylindrical grinding
Fig. 1.
Interactions between single grain and workpiece Along the grinding arc area, from the cut-in to cut-out, the grinding chip thickness is not constant, the undeformed chip thickness gradually increases in the cut-in and then gradually decreases after entering the cut-out, that the heat flow from the cut-in to cut-out will increase and then decreases, in such case, the traditional triangular heat flux distribution model is no longer suitable to predict the temperature in the grinding arc area.
For the assumed quadratic curve heat flux distribution model, the heat flux to the workpiece is given by a 2nd order polynomial function (1) In the case of the quadratic heat flux distribution, the heat source in the grinding arc area can be viewed as the formation of unlimited number of line heat source that first increases and then decreases continuously with the changes in heat intensity q(xi)=Axi2+Bxi.
As we know there are normally two kinds of grinding signals about the temperature signal, background signal and peak signal, where the background corresponds to the temperature on the ground workpiece surface, the peak temperature corresponds to the temperature at grinding point of single grain.
Interactions between single grain and workpiece Along the grinding arc area, from the cut-in to cut-out, the grinding chip thickness is not constant, the undeformed chip thickness gradually increases in the cut-in and then gradually decreases after entering the cut-out, that the heat flow from the cut-in to cut-out will increase and then decreases, in such case, the traditional triangular heat flux distribution model is no longer suitable to predict the temperature in the grinding arc area.
For the assumed quadratic curve heat flux distribution model, the heat flux to the workpiece is given by a 2nd order polynomial function (1) In the case of the quadratic heat flux distribution, the heat source in the grinding arc area can be viewed as the formation of unlimited number of line heat source that first increases and then decreases continuously with the changes in heat intensity q(xi)=Axi2+Bxi.
As we know there are normally two kinds of grinding signals about the temperature signal, background signal and peak signal, where the background corresponds to the temperature on the ground workpiece surface, the peak temperature corresponds to the temperature at grinding point of single grain.
Online since: January 2018
Authors: Abderrahim Bali, Mohamed Nadjib Oudjit, Dalila Chiheb, Mebarek Belaoura
- Deflocculating the cement grains, which is obtained by the use of organic products (condensed Formaldehyde and Melamine sulfunate or Naphthalene sulfunate), allows the cement grains in suspension in water to regain their original granularity [10].
This path leads to a significant reduction in the necessary amount of water [11], since high proportion of it, is no more, as in ordinary concrete, trapped in flocks of cement grains, and therefore is not useful for workability
However, considering the cost of additions and additives, this method allows getting the best price and takes account of the rapid loss of workability, hence the interest of a rational method of composition, leading to the control a great number of parameters with a minimum testing.
This path leads to a significant reduction in the necessary amount of water [11], since high proportion of it, is no more, as in ordinary concrete, trapped in flocks of cement grains, and therefore is not useful for workability
However, considering the cost of additions and additives, this method allows getting the best price and takes account of the rapid loss of workability, hence the interest of a rational method of composition, leading to the control a great number of parameters with a minimum testing.
Online since: August 2022
Authors: Pavla Rovnaníková, Zbyněk Keršner, Ivana Kumpová, Petr Frantík, Dominik Lisztwan, Petr Daněk
The waste brick dust was dried at 105 °C to a constant weight and then ground in a ball mill to a grain size of less than 0.3 mm (D10 = 0.885 µm, D50 = 9.600 µm and D90 = 155.416 µm).
Table 1 Tomographic data acquisition parameters Geometric parameters AAAS composite Concrete before loading Concrete after loading X-Ray source–detector distance (mm) 349.9 359.9 359.6 X-Ray source–object distance (mm) 234.0 225.0 240.5 Projection magnification (×) 1.5 1.6 1.5 Pixel size (µm) 50.02 46.76 50.03 X-Ray source parameters Accelerating voltage (kV) 230.0 230.0 230.0 Target current (µA) 190.0 195.0 210.0 Target power (W) 43.7 44.8 48.3 Image data acquisition Exposure time (ms) 240 250 230 Image averaging (×) 4 4 4 Number of projections (–) 2400 1800 1800 Tomographically obtained 3D models of the concrete were compared using a module for digital volume correlation.
From the observation of AAAS composites, it is additionally evident that the cracks pass through the matrix and pores, but not the grains of brick dust, where they copy the interfacial transition zone.
Aside from the applied load during the compressive test, the process of the production of test specimens, the size and distribution of the pores and grains of brick dust, and the possible presence of cracks caused by the maturation of the specimens may all play a role in this behaviour.
Table 1 Tomographic data acquisition parameters Geometric parameters AAAS composite Concrete before loading Concrete after loading X-Ray source–detector distance (mm) 349.9 359.9 359.6 X-Ray source–object distance (mm) 234.0 225.0 240.5 Projection magnification (×) 1.5 1.6 1.5 Pixel size (µm) 50.02 46.76 50.03 X-Ray source parameters Accelerating voltage (kV) 230.0 230.0 230.0 Target current (µA) 190.0 195.0 210.0 Target power (W) 43.7 44.8 48.3 Image data acquisition Exposure time (ms) 240 250 230 Image averaging (×) 4 4 4 Number of projections (–) 2400 1800 1800 Tomographically obtained 3D models of the concrete were compared using a module for digital volume correlation.
From the observation of AAAS composites, it is additionally evident that the cracks pass through the matrix and pores, but not the grains of brick dust, where they copy the interfacial transition zone.
Aside from the applied load during the compressive test, the process of the production of test specimens, the size and distribution of the pores and grains of brick dust, and the possible presence of cracks caused by the maturation of the specimens may all play a role in this behaviour.
Online since: September 2017
Authors: Petr Louda, Hristo Bahchedzhiev, Nikolay Petkov, Pavel Kejzlar, Totka Bakalova
Secondary requirements are a fine-grained crystalline microstructure, compressive residual stress, freedom from cracks and smooth surface morphology.
Coatings thicknesses (d) are measured by the Calotest method, using a 30-mm hard steel ball and an abrasive diamond paste with 0.1µm monocrystalline diamond grains.
An increase in the arc current (from 85 to 125) leads to an increase in Sa of 25%, and Sz and Sq of almost 50% and 30%, respectively, due to the increase in the size and number of droplets (Fig. 1, 2 and 3).
An increase in the arc current by 47% (from 85A to 125A) leads to: an increase in the coating thickness (of approximately 50%), hardness (more than double), and the elastic module (almost double); an expected change in the chemical composition of the coating (Table 2), an increase in droplet size (Fig. 3) and coating density (reducing the amount of absorbed oxygen (Table 2)); a decrease by approximately 13% of the adhesion (both values LC1 and LC2); an increase in Sa by 25%, and Sz and Sq by almost 50% and 30%, respectively, due to the increase in the size and number of droplets; a decrease in the coefficient of friction, which is registered in the three investigated loads (Table 5); a reduction of both coating wear and wear rate (between 21% and 53%) at the three investigated loads (Table 6 and 7); an approximately seven-times reduction in the wear and wear rate at 3N, and an approximately three-times reduction in the wear and wear rate at 5 and 8N.
Acknowledgement This paper was supported by the project LO1201, through the financial support of the Ministry of Education, Youth and Sports in the framework of the targeted support of the “National Programme for Sustainability I” and the OPR&DI project “Centre for Nanomaterials, Advanced Technologies and Innovation” registration number CZ.1.05/2.1.00/01.0005.We would like to thank Craig Hampson for his help with English language correction.
Coatings thicknesses (d) are measured by the Calotest method, using a 30-mm hard steel ball and an abrasive diamond paste with 0.1µm monocrystalline diamond grains.
An increase in the arc current (from 85 to 125) leads to an increase in Sa of 25%, and Sz and Sq of almost 50% and 30%, respectively, due to the increase in the size and number of droplets (Fig. 1, 2 and 3).
An increase in the arc current by 47% (from 85A to 125A) leads to: an increase in the coating thickness (of approximately 50%), hardness (more than double), and the elastic module (almost double); an expected change in the chemical composition of the coating (Table 2), an increase in droplet size (Fig. 3) and coating density (reducing the amount of absorbed oxygen (Table 2)); a decrease by approximately 13% of the adhesion (both values LC1 and LC2); an increase in Sa by 25%, and Sz and Sq by almost 50% and 30%, respectively, due to the increase in the size and number of droplets; a decrease in the coefficient of friction, which is registered in the three investigated loads (Table 5); a reduction of both coating wear and wear rate (between 21% and 53%) at the three investigated loads (Table 6 and 7); an approximately seven-times reduction in the wear and wear rate at 3N, and an approximately three-times reduction in the wear and wear rate at 5 and 8N.
Acknowledgement This paper was supported by the project LO1201, through the financial support of the Ministry of Education, Youth and Sports in the framework of the targeted support of the “National Programme for Sustainability I” and the OPR&DI project “Centre for Nanomaterials, Advanced Technologies and Innovation” registration number CZ.1.05/2.1.00/01.0005.We would like to thank Craig Hampson for his help with English language correction.
Online since: February 2018
Authors: Leonardo Roque do Carmo Souza, Sumitra S. Kandolkar
Villages Sampled
Number for Average Sizes (height x top-width) meters
In Fields
Near Canals/ Rivers
Near Seasonal Lakes
H
1-2 m
B
1-3 m
H
2-3 m
B
3-5 m
H
3-6 m
B
3-6 m
H
6-9 m
B
3-10 m
29
317
23
4
1
Typical Bund Sections: In traditional Saraswat construction a typical unit of measurement was ‘hatt’(one hand - approximately 50 centimeters).
General Soil Parameters: Classification test (natural moisture content, specific gravity, Grain size analysis and Atterberg’s limits,) and compaction test (optimum moisture content, Maximum Dry Density)were performed on the samples A, B and C to determine the geotechnical properties of the samples.
Properties Sample A Sample B Sample C 1 Specific Gravity Gs 2.73 2.72 2.75 2 Density γ g/cc 1.68 1.65 1.72 3 Moisture Content w % 12 14 14 4 Compaction Test OMC wopt % 11 12 11 MDD γmax g/cc 1.92 1.95 1.93 5 Atterbergs Limits Liquid Limit wL % 19.5 22.6 21.5 Plastic Limit wP % 14.8 16.2 15.2 Plasticity index 4.7 6.4 6.3 6 Grain Size Distribution Gravel % 31 22 38 Sand % 55 57 45 Silt % 12 18 15 Clay % 2 3 2 7 Shear stress Parameters Cohesion Kg/cm2 2.7 2.8 2.5 Friction ° 30 35 32 Soil Stabilization Studies Many studies have been done in stabilization of lateritic soils by commercially available lime and other additives [15,16].
The discrete nature of soil makes the required constitutive relationships to be exceedingly complex needing a large number of parameters to be evaluated in order to model the soil behavior accurately, hence Geostudio Sweep/w software (Fig 7) was used to find out the seepage through the soil.
Binod Bihari Satpathy,Politico-Social and Administrative History of Ancient India, DDCE/History (M.A)/SLM/Paper-10 [14] Thapar, R., Early India: From the Origins to AD 1300, London: Allen Lane, 2002 [15] B W Isah, Effect of Coconut Shell Ash on Properties of Fired Clay Brick, Journal of Civil Engineering and Environmental Technology Print ISSN: 2349-8404; Online ISSN: 2349-879X; Volume 1, Number 6; August, 2014 pp. 7-11 [16] J.
General Soil Parameters: Classification test (natural moisture content, specific gravity, Grain size analysis and Atterberg’s limits,) and compaction test (optimum moisture content, Maximum Dry Density)were performed on the samples A, B and C to determine the geotechnical properties of the samples.
Properties Sample A Sample B Sample C 1 Specific Gravity Gs 2.73 2.72 2.75 2 Density γ g/cc 1.68 1.65 1.72 3 Moisture Content w % 12 14 14 4 Compaction Test OMC wopt % 11 12 11 MDD γmax g/cc 1.92 1.95 1.93 5 Atterbergs Limits Liquid Limit wL % 19.5 22.6 21.5 Plastic Limit wP % 14.8 16.2 15.2 Plasticity index 4.7 6.4 6.3 6 Grain Size Distribution Gravel % 31 22 38 Sand % 55 57 45 Silt % 12 18 15 Clay % 2 3 2 7 Shear stress Parameters Cohesion Kg/cm2 2.7 2.8 2.5 Friction ° 30 35 32 Soil Stabilization Studies Many studies have been done in stabilization of lateritic soils by commercially available lime and other additives [15,16].
The discrete nature of soil makes the required constitutive relationships to be exceedingly complex needing a large number of parameters to be evaluated in order to model the soil behavior accurately, hence Geostudio Sweep/w software (Fig 7) was used to find out the seepage through the soil.
Binod Bihari Satpathy,Politico-Social and Administrative History of Ancient India, DDCE/History (M.A)/SLM/Paper-10 [14] Thapar, R., Early India: From the Origins to AD 1300, London: Allen Lane, 2002 [15] B W Isah, Effect of Coconut Shell Ash on Properties of Fired Clay Brick, Journal of Civil Engineering and Environmental Technology Print ISSN: 2349-8404; Online ISSN: 2349-879X; Volume 1, Number 6; August, 2014 pp. 7-11 [16] J.
Online since: July 2023
Authors: Djubir R.E. Kembuan, Telly S. Tangkere, Helena V. Opit
Number of materials
Unit
Material name
How to make
Information
1.
50
Gram
Taro flour
1) Mix the eggs
2) Enter the taro flour little by little while mixed using a mixer
3) Then print using a sponge mold.
4) After finishing the dough is printed according to taste
2.
250
Gram
Flour
3.
5
grain
Sugar
4.
200
Gram
Margarine
5.
½
Sdt
Sp
6.
½
Sdt
Vanilla
2.
Number of materials Unit Material name How to make Information 1. 100 Gram Taro flour 1) Mix taro flour, flour, baking powder and milk powder.
Then cut according to taste. 2. 250 Gram Flour 3. 5 Grain Egg 4. 250 Gram Sugar 5. 125 Gram Liquid margarine 6. 2 Sdm Milk powder Baking powder 7. ¼ Sdt SP 8. 1 Sdt Cheese 9. 500 Gram Butter Cream Table 5.
Questionnaires are a number of written questions made using a hedonic scale.
Number of materials Unit Material name How to make Information 1. 100 Gram Taro flour 1) Mix taro flour, flour, baking powder and milk powder.
Then cut according to taste. 2. 250 Gram Flour 3. 5 Grain Egg 4. 250 Gram Sugar 5. 125 Gram Liquid margarine 6. 2 Sdm Milk powder Baking powder 7. ¼ Sdt SP 8. 1 Sdt Cheese 9. 500 Gram Butter Cream Table 5.
Questionnaires are a number of written questions made using a hedonic scale.
Online since: August 2013
Authors: Hai Xia Zheng
At present, the direct payment to farmers is mainly from land conversion on converting paddy field to dry farming and Grain for Green.
The Total Economic value to improve water quality and quantity in the Miyun reservoir River Basin can be calculated by multiplying the mean WTP with the number of affected households, using the equation below: P=Mean WTP * Househould NO (5) Where, HousehouldNo is the number of households.
The downstream area provides additional clean water source to upstream, restricting industrial and agricultural development to some extent, for example: some seriously polluting enterprises are closed or disapproved, and a series of policies, such as paddy-to-dry field and Grain-for-Green, are implemented, thus regional economic development is limited.
We use Lu to value the change of urban residents’ disposable income after the implementation of ecological compensation policy, in following formula: (7) Where, Lu denotes loss of water source county residents’ disposable income of the year i, Li denotes reference county urban residents’ disposable income in previous year, Li’ denotes water source county urban residents’ disposable income in previous year, Popi denotes reference county urban on-job workers’ population, Pop’I denotes water source county urban on-job workers’ population, and n denotes the number of years for valuation after the implementation of policies.
The Total Economic value to improve water quality and quantity in the Miyun reservoir River Basin can be calculated by multiplying the mean WTP with the number of affected households, using the equation below: P=Mean WTP * Househould NO (5) Where, HousehouldNo is the number of households.
The downstream area provides additional clean water source to upstream, restricting industrial and agricultural development to some extent, for example: some seriously polluting enterprises are closed or disapproved, and a series of policies, such as paddy-to-dry field and Grain-for-Green, are implemented, thus regional economic development is limited.
We use Lu to value the change of urban residents’ disposable income after the implementation of ecological compensation policy, in following formula: (7) Where, Lu denotes loss of water source county residents’ disposable income of the year i, Li denotes reference county urban residents’ disposable income in previous year, Li’ denotes water source county urban residents’ disposable income in previous year, Popi denotes reference county urban on-job workers’ population, Pop’I denotes water source county urban on-job workers’ population, and n denotes the number of years for valuation after the implementation of policies.
Online since: May 2020
Authors: De Fu Li, Qi Wang, Qi Fei Zheng
It was found by SEM that the recrystallization of the alloy and the coarsening of the sulfide grains appeared in both materials, which was beneficial to improve the friction performance.
With the continuous development of China's railway industry, the number of diesel locomotives continues to increase, and the number of bearing production units is gradually increasing.
Through a large number of practices, it is concluded that copper-lead alloy powders with a spherical or nearly spherical shape and an oxygen content of less than 1% can meet the requirements for the production of copper-lead-steel bimetallic bearing materials.
If the temperature is too high, it may cause shrinkage, coarse grain and cracks.
With the continuous development of China's railway industry, the number of diesel locomotives continues to increase, and the number of bearing production units is gradually increasing.
Through a large number of practices, it is concluded that copper-lead alloy powders with a spherical or nearly spherical shape and an oxygen content of less than 1% can meet the requirements for the production of copper-lead-steel bimetallic bearing materials.
If the temperature is too high, it may cause shrinkage, coarse grain and cracks.
Online since: January 2007
Authors: Li Qun Chen, Zheng Chen Qiu
The alloying
elements can interact with defects (such as grain boundaries, dislocations) in crystals.
The numbers, and X, correspond to the atoms shown in Fig.1(b). 3.2.
Here ∆Q = N-Zval, where Zval is the standard number of valence electrons per atom.
The numbers, and X, correspond to the atoms shown in Fig.1(b).
The numbers correspond to the atoms shown in Fig.1(b). 4.
The numbers, and X, correspond to the atoms shown in Fig.1(b). 3.2.
Here ∆Q = N-Zval, where Zval is the standard number of valence electrons per atom.
The numbers, and X, correspond to the atoms shown in Fig.1(b).
The numbers correspond to the atoms shown in Fig.1(b). 4.