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To realize the large-scale utilization of municipal solid waste incineration (MSWI) fly ash in the field of building materials and to reduce the cost of coal mine backfill mining, the effects of the mixing ratio of cementitious materials, the particle size distribution of aggregates, and the amount and mass concentration of cementitious materials on the properties of backfill materials were experimentally investigated, and the microstructure of the hydration products was analyzed. The results showed that as the mass ratio of MSWI fly ash to bottom ash increased, the rate of expansion of the cementitious system continued to increase, and the compressive strength of the cementitious system continued to decrease. The Al (aluminum) and AlN (aluminum nitride) in the fly ash reacted with water to generate gas, causing the expansion of the cementitious materials; NaOH increased the alkalinity of the solution, which promoted the formation of more bubbles, thereby improving the expansion performance of the cementitious material. When the content of NaOH was 0.9%, the sample rate of expansion could reach 15.9%. The addition of CaCl2 promoted the early hydration reaction of the cementitious material, forming a dense microstructure, thus improving the early strength and rate of expansion of the cementitious material. The compressive strength of the backfill body increased as the fractal dimension of the aggregate particles increased, and the particle grading scheme of group S1 was optimal. The 1-day, 3-day, and 28-day strengths of the backfill body of group S1 reached 0.72 MPa, 1.43 MPa, and 3.26 MPa, respectively. It is recommended to choose a backfill paste concentration ranging between 78.5% and 80% and a reasonable amount of cementitious material between 20% and 25%. After the MSWI fly ash was prepared as a backfill material, the leaching of potentially harmful elements in the fly ash was greatly reduced, and the concentration of dioxin was reduced to 13 ng TEQ/kg. This was attributed to the dilution of the cement, the physical encapsulation of gel products, and the isomorphous replacement of Ca2+ in calcium aluminate chloride hydrate. [ABSTRACT FROM AUTHOR]

Alite-ye'elimite-belite-ferrite cement (AYBFC) integrates the advantages of calcium sulfoaluminate cement and Portland cement, but its ultra-early strength needs to be further improved when applied to rush repair and construction works. In this study, the ultra-early strength of AYBFC was improved using lithium carbonate (Li2CO3) and superplasticizer. The results showed that an appropriate amount of Li2CO3 could significantly improve the ultra-early strength of AYBFC, since it was capable of promoting the hydration reaction of AYBFC. After polycarboxylate superplasticizer was doped on this basis, the ultra-early compressive strength of AYBFC was further improved. This was because the superplasticizer could markedly enhance the matrix compactness despite its inhibitory effect on the hydration reaction of cement and the generation of hydration products. [ABSTRACT FROM AUTHOR]

The fatigue performance of cementitious composites that affects the service life of structures is particularly sensitive to the initial defects in cementitious matrix and interfacial transition zone. Nano‐ZrO2 (NZ), characterized by high strength and toughness as well as good dispersibility, can improve the compactness of cementitious composites. This paper investigated the modifying effect and mechanisms of NZ on the compressive fatigue performance of cementitious composites, including fatigue life, strength, and deformation behaviors. The experimental results show that adding NZ extends the fatigue life of cementitious composites by an order of magnitude and increases the fatigue failure strain by 11.9%. The microstructural analysis verifies that NZ can deflect the fatigue micro‐cracks, fill the micro‐pores and reduce the growth space of CH crystal size. The modified microstructures potentially lead to fatigue of cementitious composites starting from generating more nano‐cracks in both cementitious matrix and interfacial transition zone, thereby improving the fatigue performance of the composites. Highlights: Nano‐ZrO2 (NZ) is added into concrete to improve compressive fatigue propertyThe fatigue life and failure strain of concrete are enhanced by the addition of NZThe morphology of fatigue fracture surface of concrete with/without NZ is observedThe fatigue equation of cementitious composites with/without NZ is developed [ABSTRACT FROM AUTHOR]

This article reports a comparative analysis between glass waste and fly ash (which is the most studied waste for the alkali-activated products) to measure their effectiveness as a sole precursor to produce geopolymers. Globally, around 11.4 million tonnes of glass waste is generated per annum, and this needs to be managed properly. To address this issue, in this study, glass waste which was mostly manufactured bottles and containers was used in pulverized form. The molarity of the sodium hydroxide (NaOH) solution was kept as 6 M, 8 M, and 10 M. The sodium silicate-to-sodium hydroxide (Na2SiO3/NaOH) solution mix ratio was varied between 1.5 and 3.5. Mechanical (compressive and flexural strength) and durability (resistance to different levels of sulfuric acid) aspects were studied along with micro-analysis (structural, elemental, and thermal). Controlled ambient temperature curing was followed for all the samples. Our findings showed that mechanical properties were dependent on the molarity, silicate modulus, and alkaline mixture (AM) ratio. The glass waste showed substantial amount of long-term strength development over fly ash with a maximum compressive strength gain at 28 d and 90 d curing age of 90% and 194% for 8M1.5AM and 6M1.5AM mixture, respectively. For flexural strength, it was 49% and 62% gain at 28-d and 90-d curing, respectively, for 10M1.5AM mixture. The glass waste also offered relatively higher resistance to acid attack with a maximum compressive strength loss of 61% and 55.7%, whereas fly ash-based mixtures recorded 75% and 71.73% reduction for 5% and 3% H2SO4 attack for 28 d, respectively. Field emission scanning electron microscopy (FE-SEM) revealed that the glass waste specimens were more compact than fly ash-based specimens. Thermogravimetric analysis (TGA) results indicate that glass waste-based geopolymers are more thermally resistant than fly ash-based geopolymers when exposed to a systematic increment in temperature. Ultimately, promising results in terms of mechanical and durability aspects propose the use of glass waste as a binder in geopolymeric masonry mortar applications. Glass waste has a full potential to be a sole precursor to produce geopolymer under ambient temperature curing conditions. This will contribute towards sustainable environment by paving path for an effective utilization of the glass waste. [ABSTRACT FROM AUTHOR]

To realize the large-scale utilization of municipal solid waste incineration (MSWI) fly ash in the field of building materials and to reduce the cost of coal mine backfill mining, the effects of the mixing ratio of cementitious materials, the particle size distribution of aggregates, and the amount and mass concentration of cementitious materials on the properties of backfill materials were experimentally investigated, and the microstructure of the hydration products was analyzed. The results showed that as the mass ratio of MSWI fly ash to bottom ash increased, the rate of expansion of the cementitious system continued to increase, and the compressive strength of the cementitious system continued to decrease. The Al (aluminum) and AlN (aluminum nitride) in the fly ash reacted with water to generate gas, causing the expansion of the cementitious materials; NaOH increased the alkalinity of the solution, which promoted the formation of more bubbles, thereby improving the expansion performance of the cementitious material. When the content of NaOH was 0.9%, the sample rate of expansion could reach 15.9%. The addition of CaCl2 promoted the early hydration reaction of the cementitious material, forming a dense microstructure, thus improving the early strength and rate of expansion of the cementitious material. The compressive strength of the backfill body increased as the fractal dimension of the aggregate particles increased, and the particle grading scheme of group S1 was optimal. The 1-day, 3-day, and 28-day strengths of the backfill body of group S1 reached 0.72 MPa, 1.43 MPa, and 3.26 MPa, respectively. It is recommended to choose a backfill paste concentration ranging between 78.5% and 80% and a reasonable amount of cementitious material between 20% and 25%. After the MSWI fly ash was prepared as a backfill material, the leaching of potentially harmful elements in the fly ash was greatly reduced, and the concentration of dioxin was reduced to 13 ng TEQ/kg. This was attributed to the dilution of the cement, the physical encapsulation of gel products, and the isomorphous replacement of Ca2+ in calcium aluminate chloride hydrate.

Alite-ye’elimite-belite-ferrite cement (AYBFC) integrates the advantages of calcium sulfoaluminate cement and Portland cement, but its ultra-early strength needs to be further improved when applied to rush repair and construction works. In this study, the ultra-early strength of AYBFC was improved using lithium carbonate (Li2CO3) and superplasticizer. The results showed that an appropriate amount of Li2CO3 could significantly improve the ultra-early strength of AYBFC, since it was capable of promoting the hydration reaction of AYBFC. After polycarboxylate superplasticizer was doped on this basis, the ultra-early compressive strength of AYBFC was further improved. This was because the superplasticizer could markedly enhance the matrix compactness despite its inhibitory effect on the hydration reaction of cement and the generation of hydration products.

The combination of experimental programs and finite element numerical methods is adopted to explore the durability of WBC (waste brick concrete). Rapid freeze-thaw and flexural tests are performed with the content of WBCA (waste brick coarse aggregate) and the number of freeze-thaw cycles as variables. Freeze-thaw damage mechanisms at the microscopic interfaces of recycled concrete are revealed by scanning electron microscopy. The evolution laws of relative dynamic elastic modulus, mass loss rate, and flexural and tensile strength loss rate are analyzed. Combined with numerical simulations, the temperature stress distribution and three-point bending damage law of concrete with 100 % WBCA content at different freeze-thaw times are shown, and practical examples are verified. Results showed that WBC with high WBCA content has poor freeze-thaw resistance. Furthermore, WBC's freezing resistance and bending properties deteriorate as the number of freeze-thaw cycles increases. Possible damaged locations in the concrete are determined by stress analysis. The finite element model can predict the flexural performance of WBC better with an error of 4.5 % for the peak load and 3.5 % for the peak displacement of the beam. Therefore, the presented model can also be used to predict the performance of concrete after freezing and thawing under any WBCA replacement rate.

In order to improve the durability of asphalt pavement and prolong the service life of heavy traffic asphalt pavement, graphene oxide (GO) and rubber powder (RP) were used as composite modifiers to modify matrix asphalt. The high-temperature rheological properties of composite-modified asphalt at different temperatures and frequencies were analyzed. The influence of different stress levels on the viscoelastic properties of composite-modified asphalt was evaluated. The low-temperature rheological properties of composite-modified asphalt were studied. The difference between RP-modified asphalt and GO/RP composite-modified asphalt was analyzed, and the mechanism of GO and RP on asphalt modification was explored. The results show that the composite-modified asphalt has good rheological properties at low temperature, relatively smooth surface and stable network structure, which improves the segregation problem of RP in matrix asphalt. At present, GO and RP are rarely used as composite modifiers to modify matrix asphalt at home and abroad, which is an innovation in material selection. [ABSTRACT FROM AUTHOR]

In order to solve the problem of poor crack resistance and frost resistance of semi-rigid base, rubber powder and retarder were added to a semi-rigid base mixture. First, 61 mixing ratios were determined. Then, through the unconfined compressive strength, splitting strength, and other tests, the mechanical, crack, and frost resistance properties of the retarded composite semi-rigid base coarse mixture with rubber powder were studied. Finally, the macro and micro properties of the two kinds of admixture composite semi-rigid base coarse mixtures were studied by means of SEM and industrial CT. The results show that rubber powder and retarder can effectively improve the cracking and freezing resistance of the mixture. After five freeze–thaw cycle tests, the strength of the retarded composite semi-rigid base material mixed with rubber powder decreased slightly compared with the mixture without additives. It can be seen that rubber powder improved the frost resistance of the mixture. When the content of rubber powder was 1.5%, the BDR value of the mixture increased by 8.8%. With the increase of unconfined compressive strength, splitting strength, and flexural tensile strength at 28 d and 90 d, it was found that the retarder improved the middle and late strength of the mixture. When the content of retarder was 0.09%, the increase of unconfined compressive strength at 28 d reached 3.9%. The addition of rubber powder and retarder improved the distribution of internal pores, the proportion of large pores decreased, and the proportion of small pores increased. The retarder changed the morphology of hydration products, formed a dense network supporting structure, further refined the pores, and reduced the porosity of the mixture. The proportion of pores with a volume greater than 100 mm3 in the total pore volume decreased by 26.01%, and the proportion of medium pores increased by 13.07%, thereby improving the mechanical properties of the mixture. [ABSTRACT FROM AUTHOR]

Non-metallic fractions (NMFs) from waste printed circuit boards (PCBs) are mostly composed of cured resin and fiber. In this study, NMF material from a PCB was ground into powder and added into matrix asphalt to produce PCB-NMF-modified asphalt. To improve the compatibility of PCB-NMF and asphalt, a compatibilizer consisting of tung oil and glycerol was also developed. The optimum compatibilizer content was determined to be 8% by weight of the PCB-NMF through a series of laboratory tests, including the softening point, penetration, ductility, and softening point difference (SPD). The micro-mechanism of NMF powder-modified asphalt was analyzed through Fourier transform infrared spectroscopy (FTIR) and a scanning electron microscope test (SEM). The performances of PCB-NMF-modified asphalt were evaluated by the dynamic shear rheology (DSR) test and the low-temperature bending beam rheometer (BBR) test. The optimum compatibilizer content was 8% by weight of the NMF powder and the optimum content of NMF powder was determined to be 30% by weight of the asphalt based on a comprehensive evaluation. The results show that PCB-NMF can significantly improve stiffness, rutting resistance, high-temperature stability, and temperature sensitivity of asphalt material at an appropriate content. The BBR tests revealed that PCB-NMF slightly weakened the cracking resistance of asphalt at low temperatures. The SEM test showed that the addition of a compatibilizer can increase the compatibility by making the NMF powder evenly dispersed. The FTIR test results implied that a chemical reaction may not have happened between PCB-NMF, compatibilizer, and the matrix asphalt. Overall, it is a promising and sustainable way to utilize PCB-NMF as a modifier for asphalt material and reduce electronic waste treatment at a low cost. [ABSTRACT FROM AUTHOR]

The strengthening application of brick concrete recycled coarse aggregate (BCRCA) has become a “troublesome issue.” In this sense, an in-depth study on the strengthening method of BCRCA is needed. In order to improve the strengthening effect of BCRCA and perform the large-scale application of brick concrete waste, the strengthening method of BCRCA was investigated. Briefly, the performance of BCRCA was initially analyzed. Then, the pore characteristics of BCRCA were tested by CT scanning technology. The evaluation index of filling saturation was proposed. Finally, the BCRCA was strengthened by the negative pressure, and the influences of key parameters such as negative pressure, negative pressure time, negative pressure temperature, and stirring times on the strengthening effect were investigated. The test results showed that the best performance can be obtained by using the following parameters: negative pressure from −55 kPa to −80 kPa, the negative pressure time from 6 to 14 min, the negative pressure temperature from 40 to 80°C, and the stirring times from 1 to 4 times. Combined with the influence of negative pressure strengthening process parameters on filling saturation, it can be determined that a negative pressure of −75 kPa, a negative pressure time of 12 min, and a negative pressure temperature of 70°C with two times of stirring were the best negative pressure strengthening parameters. The unconfined compressive strength and indirect tensile strength reached 4.9 and 0.55 MPa, respectively, when the reinforced BCRCA was used for the cement-stabilized macadam. Therefore, the negative pressure strengthening process parameters determined in this study can achieve a good strengthening effect.

[Display omitted] • The CUO has systemic vertical variations in mineral assemblages and pitchblende geochemistry. • The vertical variations were caused by the ascent of deep oxidizing fluid and decreased upwardly during U mineralization. • REE of pitchblende could be used to guide deep uranium exploration. The Changjiang uranium (U) orefield in northern Guangdong (South China) contains several important granite-related uranium deposits, including the Mianhuakeng deposit. The hydrothermal evolution and mineralization mechanism of the deposit remain unclear, and hence in this study we analyzed the mineral compositional variations of pitchblende from different elevation (−300 to −50 m) in the orebody at Mianhuakeng deposit. The results indicate that with decreasing depth, the hydrothermal mineral assemblage changes from a reducing one (pitchblende, pyrite, and chlorite) to a moderately oxidizing one (pitchblende, coffinite, hematite, and goethite). The contents of U, Sr, ∑REE, U/Th, and LREE/HREE ratios in the pitchblende decrease (whereas the Cu-Pb-Zn-Ni-Co-Sc-Rb contents increase) progressively with decreasing depth. Also, Ce anomaly (Ce/Ce*) changes from positive to negative, and Eu anomaly (Eu/Eu*) becomes more negative with decreasing depth. We interpreted such vertical variations to be caused by the ascent of deep, mid-to-high temperature, highly-oxidizing ore-forming fluid, which was reduced by early-stage reducing minerals in the wallrock, a process that also formed the mineralization at Changjiang. In addition, the pitchblende REE distribution patterns and Eu/Eu* at depth (−300 m) resemble those of the Zhuguang pluton, indicating that the ore-forming materials were originated from the U-bearing granite wallrocks. Therefore, the Ce/Ce* and Eu/Eu* variations of pitchblende can be used to guide deep uranium ore exploration. [ABSTRACT FROM AUTHOR]

One of the main challenges in group therapy with drug-addicted patients is collective pseudomentalization, i.e., a group discourse consisting of words and clichés that are decoupled from any inner emotional life and are poorly related to external reality. In this study, we aimed to explore the phenomenology of pseudomentalization and how it was addressed by the therapist in an outpatient group for drug-addicted patients. The group was composed of seven members, and the transcripts of eight audio-recorded sessions (one per month) were rated and studied. The interventions of the therapist were measured with the mentalization-based group therapy (MBT-G) adherence and quality scale by independent raters. Two sessions, one with the highest and one with the lowest adherence, were selected, and the clinical sequences of pseudomentalization were analyzed in a comparative way. The findings revealed that pseudomentalization does occur as a collective phenomenon, akin to "basic assumptions" of Wilfred Bion, which we reconceptualized in this study. Any pseudomentalization seemed to be reinforced by the therapist when she was presenting frequent and long interventions, when abstaining from the management of group boundaries, when providing questions focused more on content than on the mental states of the group members, and when not focusing on emotions. However, the ultimate source of collective pseudomentalization seemed to be the fear of the group members of being overwhelmed by painful emotions, mental confusion, and a loss of identity. The findings also indicated that the principles of MBT-G may be a good antidote to pseudomentalization. [ABSTRACT FROM AUTHOR]

Abstract This paper reports on activities carried out as part of a pre-conservation studies of the painting by Dmitry Levitsky, “The Portrait of F.P. Makerovsky in a Masquerade Costume” (1789, the State Tretyakov Gallery). Samples were taken and prepared for further study within the following algorithm. Using optical microscopy of cross-sections of the samples taken, structural elements of layered compositions were revealed and external differences between them were established. X-ray fluorescence spectroscopy was used to evaluate the elemental composition of the painting surface and cross-sections of samples. Scanning electron microscopy combined with energy dispersive X-ray spectroscopy was used to clarify the elemental composition of each of the structural elements of the samples taken, their submicro- and microdimensional inclusions, to map the distribution of chemical elements over the studied surface, and to determine the dispersion of organic and inorganic components contained in the material. Micro-FTIR was used to identify functional groups and to determine the main classes of inorganic compounds, as well as binders, used, including in the local analysis of micro-inclusions. The list of specific chemical compounds in the composition of the studied paint layers and grounds, which included an examination of the varnish coating, was determined with micro-Raman spectroscopy using data obtained by the above methods. As a result of the study, complementary information was obtained on the chemical composition of the inorganic components used, of the binder and of the varnish coating, which is required for further conservation of this work of art.

One of the main challenges in group therapy with drug-addicted patients is collective pseudomentalization, i.e., a group discourse consisting of words and clichés that are decoupled from any inner emotional life and are poorly related to external reality. In this study, we aimed to explore the phenomenology of pseudomentalization and how it was addressed by the therapist in an outpatient group for drug-addicted patients. The group was composed of seven members, and the transcripts of eight audio-recorded sessions (one per month) were rated and studied. The interventions of the therapist were measured with the mentalization-based group therapy (MBT-G) adherence and quality scale by independent raters. Two sessions, one with the highest and one with the lowest adherence, were selected, and the clinical sequences of pseudomentalization were analyzed in a comparative way. The findings revealed that pseudomentalization does occur as a collective phenomenon, akin to “basic assumptions” of Wilfred Bion, which we reconceptualized in this study. Any pseudomentalization seemed to be reinforced by the therapist when she was presenting frequent and long interventions, when abstaining from the management of group boundaries, when providing questions focused more on content than on the mental states of the group members, and when not focusing on emotions. However, the ultimate source of collective pseudomentalization seemed to be the fear of the group members of being overwhelmed by painful emotions, mental confusion, and a loss of identity. The findings also indicated that the principles of MBT-G may be a good antidote to pseudomentalization.

Wind turbine duct put forward higher requirements for the performance of grouting materials. In order to obtain more economical high strength grouting materials (HSG), three kinds of low price main components, cement, quartz sand (QS) and fly ash microspheres (MS) were utilized and developed. Macro performance and micro-analysis of the HSG were conducted. The macro performance tests revealed that the mix proportion of HSG is determined as, cement: QS: MS: superplasticizer: swelling agent = 80:10:10:0.3:0.12, water binder ratio is determined as 0.26. Compressive and flexural strength of the HSG exceeding 120 MPa and 20 MPa respectively. The HSG also showed good fluidity and homogeneity. The micro-analysis showed that a complete and continuous micro-structure was formed and interface transition zone could not be observed. XRD and TG-DSC results meant that the amount of AFt increased. On the contrary, the amount of Ca(OH) _2 decreased. pore diameter of the HSG was mostly 10 nm. The addition of swelling agent and MS did not changed the types of hydration products of HSG, but the pore structure was optimized. Due to the cheap components, HSG contributed higher profits with the lower price, and which perform good economic benefits and market competitiveness.

The main purpose of this study is to determine the metakaolin (MK) impacts on the concrete durability when the concrete is subjected to joint corrosion of SO42−,Mg2+ and, Cl−. Four groups of concrete test samples, which contained different MK contents, were designed and tested in order to see their physical property changes and macro-morphology differences during the cyclic corrosion process. And a series of approaches, including XRD, FTIR, SEM, and EDS, were applied to study the concrete phase composition changes and the micro-morphology features of all groups. According to the test results, when reaching 20 cycles, the concrete sample with 10% MK showed the best concrete physical properties; when reaching 120 cycles, the concrete with 5% MK content showed the best durability, produced similar amount of corrosion products to ordinary concrete, and presented relatively compacted micro-structure and small internal porosity. Mg2+ actually has a great impact on metakaolin. The corrosion product quantity increased significantly when MK admixture reached 15%. Due to the great number of produced M-S-H, the corrosive ions damaged the concrete for a second time, leading to serious aggregate peeling-off, powder surface of test samples, and porous micro-structure.

In order to improve the durability of asphalt pavement and prolong the service life of heavy traffic asphalt pavement, graphene oxide (GO) and rubber powder (RP) were used as composite modifiers to modify matrix asphalt. The high-temperature rheological properties of composite-modified asphalt at different temperatures and frequencies were analyzed. The influence of different stress levels on the viscoelastic properties of composite-modified asphalt was evaluated. The low-temperature rheological properties of composite-modified asphalt were studied. The difference between RP-modified asphalt and GO/RP composite-modified asphalt was analyzed, and the mechanism of GO and RP on asphalt modification was explored. The results show that the composite-modified asphalt has good rheological properties at low temperature, relatively smooth surface and stable network structure, which improves the segregation problem of RP in matrix asphalt. At present, GO and RP are rarely used as composite modifiers to modify matrix asphalt at home and abroad, which is an innovation in material selection.

In order to solve the problem of poor crack resistance and frost resistance of semi-rigid base, rubber powder and retarder were added to a semi-rigid base mixture. First, 61 mixing ratios were determined. Then, through the unconfined compressive strength, splitting strength, and other tests, the mechanical, crack, and frost resistance properties of the retarded composite semi-rigid base coarse mixture with rubber powder were studied. Finally, the macro and micro properties of the two kinds of admixture composite semi-rigid base coarse mixtures were studied by means of SEM and industrial CT. The results show that rubber powder and retarder can effectively improve the cracking and freezing resistance of the mixture. After five freeze–thaw cycle tests, the strength of the retarded composite semi-rigid base material mixed with rubber powder decreased slightly compared with the mixture without additives. It can be seen that rubber powder improved the frost resistance of the mixture. When the content of rubber powder was 1.5%, the BDR value of the mixture increased by 8.8%. With the increase of unconfined compressive strength, splitting strength, and flexural tensile strength at 28 d and 90 d, it was found that the retarder improved the middle and late strength of the mixture. When the content of retarder was 0.09%, the increase of unconfined compressive strength at 28 d reached 3.9%. The addition of rubber powder and retarder improved the distribution of internal pores, the proportion of large pores decreased, and the proportion of small pores increased. The retarder changed the morphology of hydration products, formed a dense network supporting structure, further refined the pores, and reduced the porosity of the mixture. The proportion of pores with a volume greater than 100 mm3 in the total pore volume decreased by 26.01%, and the proportion of medium pores increased by 13.07%, thereby improving the mechanical properties of the mixture.

Non-metallic fractions (NMFs) from waste printed circuit boards (PCBs) are mostly composed of cured resin and fiber. In this study, NMF material from a PCB was ground into powder and added into matrix asphalt to produce PCB-NMF-modified asphalt. To improve the compatibility of PCB-NMF and asphalt, a compatibilizer consisting of tung oil and glycerol was also developed. The optimum compatibilizer content was determined to be 8% by weight of the PCB-NMF through a series of laboratory tests, including the softening point, penetration, ductility, and softening point difference (SPD). The micro-mechanism of NMF powder-modified asphalt was analyzed through Fourier transform infrared spectroscopy (FTIR) and a scanning electron microscope test (SEM). The performances of PCB-NMF-modified asphalt were evaluated by the dynamic shear rheology (DSR) test and the low-temperature bending beam rheometer (BBR) test. The optimum compatibilizer content was 8% by weight of the NMF powder and the optimum content of NMF powder was determined to be 30% by weight of the asphalt based on a comprehensive evaluation. The results show that PCB-NMF can significantly improve stiffness, rutting resistance, high-temperature stability, and temperature sensitivity of asphalt material at an appropriate content. The BBR tests revealed that PCB-NMF slightly weakened the cracking resistance of asphalt at low temperatures. The SEM test showed that the addition of a compatibilizer can increase the compatibility by making the NMF powder evenly dispersed. The FTIR test results implied that a chemical reaction may not have happened between PCB-NMF, compatibilizer, and the matrix asphalt. Overall, it is a promising and sustainable way to utilize PCB-NMF as a modifier for asphalt material and reduce electronic waste treatment at a low cost.

This work explored the correlation among the physical and mechanical parameters of concrete in marine environments during corrosion. Concrete materials with varied water–cement ratios (w/c) were soaked in four kinds of simulated seawater, including a compound solution of sodium chloride (NaCl) and magnesium sulfate (MgSO4), a solution of MgSO4, a solution of sodium sulfate (Na2SO4), and clear water. The macroscopic physical and mechanical parameters, such as compressive strength, tensile strength, mass change and ultrasonic wave velocity, were measured. The damage mechanism of corrosion products and microstructures was analyzed using microscopic approaches including scanning electron microscopy (SEM), X-ray diffraction (XRD), etc. Linear correlation was carried out on the abovementioned physical parameters, and the results revealed that, during corrosion, the correlation between compressive and tensile strength and mass (excluding Na2SO4 solution) is positive (mostly highly correlated), while that with wave velocity is poor (mostly moderately correlated).

This paper reports on activities carried out as part of a pre-conservation studies of the painting by Dmitry Levitsky, "The Portrait of F.P. Makerovsky in a Masquerade Costume" (1789, the State Tretyakov Gallery). Samples were taken and prepared for further study within the following algorithm. Using optical microscopy of cross-sections of the samples taken, structural elements of layered compositions were revealed and external differences between them were established. X-ray fluorescence spectroscopy was used to evaluate the elemental composition of the painting surface and cross-sections of samples. Scanning electron microscopy combined with energy dispersive X-ray spectroscopy was used to clarify the elemental composition of each of the structural elements of the samples taken, their submicro- and microdimensional inclusions, to map the distribution of chemical elements over the studied surface, and to determine the dispersion of organic and inorganic components contained in the material. Micro-FTIR was used to identify functional groups and to determine the main classes of inorganic compounds, as well as binders, used, including in the local analysis of micro-inclusions. The list of specific chemical compounds in the composition of the studied paint layers and grounds, which included an examination of the varnish coating, was determined with micro-Raman spectroscopy using data obtained by the above methods. As a result of the study, complementary information was obtained on the chemical composition of the inorganic components used, of the binder and of the varnish coating, which is required for further conservation of this work of art. [ABSTRACT FROM AUTHOR]

The international trend of positioning the preschool as a pre-academic learning environment is challenging for preschool teachers, as it necessitates a balance between emotionally supportive interaction and goal-oriented learning instruction. However, previous research suggests that the complexities of such interactions need to be further studied. This article contributes by presenting a very detailed exploration of how social adaptation is pursued in a goal-oriented documentation activity. The study used a micro-sociological approach, characterized by the careful analysis of verbal and nonverbal interactions. Two research questions were raised: (1) How is social adaptation pursued in verbal and nonverbal interactions in preschool teacher–child relationships during a goal-oriented activity? and (2) How can social adaptation in the preschool context be understood in terms of a “deference-emotion system”? Interactions between a teacher and child in two video-recorded episodes were transcribed and sequentially analyzed thoroughly. The findings suggest that the interactions were regulated through an informal system of social sanctions, in which nonverbal signs of deference played a key role. The interaction was shown to be embedded in an institutional context that advocates goal-oriented instruction, thus highlighting the challenge of preschool teaching in attempting to promote goal-oriented processes while simultaneously maintaining respectful, caring teacher–child relationships.

The paper investigates issues, concerning financial planning at the enterprise. Methods and models of financial forecasting are analyzed and their unification is proposed. The main problems of financial instruments using (such as financial planning) are described. Planning is important element of management, which ensures achievement of strategic priorities. Effective financial planning is essential tool of achieving of the main goals of the enterprise - profit maximization and cost of the enterprise. As market conditions in Ukrainian market of goods and services have its own specificity, which is defined, on the one hand, by means of analysis, formation and allocation of financial resources, and, on the other hand, the sources of reserves increasing, in order to implement the operating and investment activities to ensure their sustainable financial development. It should be noted that the formation of these processes has a significant impact on both objective and subjective factors, such as instability of tax policy and regulatory legislation for national currency, the impact of the global economic crisis, reducing the resources and available current assets etc. Thus, the increasing volatility of external environment requires managerial entities to speed decision-making and direct financial planning and forecasting, in order to reduce the impact of exogenous and endogenous factors on the financial activities of enterprises.

This discussion with the geographer Marie Chabrol, is devoted to the in-depth mutations taking place in Château-Rouge, an old immigrant neighbourhood of Paris internationally known for being a major African commercial centrality in a European city. She emphasizes her interest in the urban temporalities and individual trajectories and talks about the influence of microstoria on her own work at a theoretical level.

Highlights • A combination of DSC and PXRD, Raman, FTIR and Cryo-SEM is used for investigating CH 4 -CO 2 hydrate formation. • Mechanism of hydrate formation from CH 4 -CO 2 gas mixture is identified. • A way of ultrasonic dispersion for improving gas consumption is proposed. Abstract Energy shortage and carbon emission reduction are the two big problems in the development of human society. The technologies involving CH 4 -CO 2 binary hydrate is considered to be promising for CH 4 recovery and carbon emission reduction. The DSC, Raman, FTIR, Cryo-SEM and PXRD are employed to investigate the thermal process, the micro structure and compositions of the CH 4 -CO 2 hydrate formation and decomposition. The investigations reveal that there are not one kind of hydrate but rather multi-kinds of hydrates coexistence during the hydrate formation. The mechanism of gas hydrate formation could be considered as, under a certain condition, the component with lower enthalpy prior to entrap the cavities to stabilize the hydrate cages in the process of constructing hydrate cages by water molecules, and once the relevant cages are stabilized, the hydrates thereby exist. To fully disperse the oil additive (e.g. CP) into water can effectively improve the gas consumption and enhance CO 2 separation efficiency in the process of CH 4 -CO 2 binary hydrate formation. The methods presented here can also be employed for other fields such as hydrate-based sea-water desalination, CO 2 separation and H 2 purification from IGCC syngas, gas transportation, and other fields. [ABSTRACT FROM AUTHOR]

The use of lime and fly ash to improve the properties of certain types of soil is well established. However, the potential of fly ash to control the adverse effects of lime-treated gypseous/sulphatic soil has not been well investigated. In the present work, an attempt is made to quantify the fly ash content used to suppress the susceptible behavior of lime-treated gypseous soil. Series of one-dimensional swell and compressibility analyses are performed on various combinations of expansive soil with a predominance of montmorillonite mineral containing lime, gypsum (0–6%), and fly ash (0–30%). It is observed that the volume change behavior of the lime-treated gypseous soil is not controlled completely by addition of fly ash. However, the maximum improvement in the volume change behavior of the lime-treated gypseous soil is observed with a 20% fly ash content, and hence, can be taken as the Optimum Fly ash Content (OFC). Micro-analyses revealed that the relative dominance of the change in gradation and the formation of cementitious compounds of different compositions and ettringite crystals are the key factors in controlling the volume change behavior of lime-treated gypseous soil with fly ash. However, several factors, such as the types of minerals present in the soil, the types of fly ash and lime, and other physico-chemical environmental conditions (temperature, method of curing, and so on), are seen in the present study to affect the value of the obtained OFC. [ABSTRACT FROM AUTHOR]

Copyright of Electronic Turkish Studies is the property of Electronic Turkish Studies and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Bait Al-Mashura Journal is the property of Bait Al-Mashura Journal and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

For describing the slip differential heat between two neighboring particles of magnetorheological fluids (MRFs) in shear and squeeze modes, a theoretical model was developed in this study based on micromechanics and microstructures. Firstly, the interaction force and the contact stress during the shear and squeeze deformation was analyzed based on the magnetic dipole theory and the Hertzian contact theory. And then the motion and the relative velocity of particles were analyzed by assuming the incline or bending of a single chain ordered in MRFs. Furthermore, the slip differential heat flow caused by the friction of neighboring particles in MRFs was analyzed based on the tribology theory. The model takes into account the effect of the main influencing factors on the slip differential heat flow between two neighboring particles in a single chain of MRFs in shear and squeeze modes, such as the magnetic induction intensity, the size of particles, the number of the particles in a single chain, the relative velocity between the upper and lower walls in shear mode and the squeeze velocity in squeeze mode. Using the proposed model, the individual effect of typical governing parameters on slip differential heat flow under the realistic conditions of the magnetorheological clutch and damper was investigated by the numerical simulation. The results indicate that these factors have great influences on the slip differential heat flow, and the proposed model can satisfactorily describe the main micro-characteristics of the slip differential heat of MRFs in shear and squeeze modes.

Since isomorphous properties are common in many natural minerals, it is difficult to distinguish these minerals due to their similar characteristics under a microscope. The chemical composition and structure of these kinds of minerals can be obtained by using X-ray Diffraction Analysis, Electron Microscope Analysis, Electron Microprobe Analysis and Ion Probe Analysis, which can provide useful information for mineral identification. Galena (Pb 86.60%, S 13.40%) and sphalerite (Zn 67.10%, S 32.90%) contained in lead-zinc ore are more typical and are readily available to use as examples. The characteristic of minerals were determined preliminarily under the optical microscopy, and then the lead-zinc ore were qualitatively determined by using the in-situ micro-analysis function of RIGAKU ZSX Primus X-ray Fluorescence Spectrometer, which was applied to explain various characteristic of minerals. The experimental results show that the anomaly elements (S, Pb, Zn and Cd) were distinguished in some lead-zinc ores. According to the distribution analysis of the anomaly elements (Zn, S, Fe and Cd) in some sphalerite, 2D or 3D distribution images were established and the anomaly areas of elements are highly consistent. Under the real-time monitoring by charge-coupled device, the target area at the ore sample was quantitatively analyzed to identify the ore with its theoretical chemical components. The relative standard deviation (RSD, n=11) of determination of sphalerite sample components was less than 4%, which is comparable to the values obtained by Electron Microprobe. A new in-situ micro-analysis method of determining major and minor elements in lead-zinc ore is presented and is proved to be a fast non-invasive analytical technique. On the basis of the above analysis, a novel reasonable qualitative or quantitative analytical method for the identification of lead-zinc ore has been established, which provides a new method for the identification rock and minerals.

A simple, accurate, and economical method has been proposed to measure formaldehyde in aqueous samples. The method is based on quantification of classical chromotropic acid – formaldehyde violet spots developed on TLC. Different parameters such as concentration of chromotropic and sulfuric acid, time of heating and order of application of reagents have been studied to find out the optimum working procedure. Spots have been quantified by scanning the spotted TLC and analyzing the image in computer with Visual Basic 6.0 based graphic application. The study consisted of developing an appropriate calibration line, analyzing artificial and real samples, and comparing the new method with a standard spectrophotometric method (NIOSH Method-3500, 1994). It has been concluded that the present method had the capability for measuring formaldehyde in aqueous samples at trace level with high precision and accuracy, particularly when dealing with turbid and small volume samples where the standard method failed.

Copyright of Ricerche di Pedagogia e Didattica is the property of Universita di Bologna, Dipartimento di Scienze dell'Educazione and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This work explored the correlation among the physical and mechanical parameters of concrete in marine environments during corrosion. Concrete materials with varied water–cement ratios (w/c) were soaked in four kinds of simulated seawater, including a compound solution of sodium chloride (NaCl) and magnesium sulfate (MgSO4), a solution of MgSO4, a solution of sodium sulfate (Na2SO4), and clear water. The macroscopic physical and mechanical parameters, such as compressive strength, tensile strength, mass change and ultrasonic wave velocity, were measured. The damage mechanism of corrosion products and microstructures was analyzed using microscopic approaches including scanning electron microscopy (SEM), X-ray diffraction (XRD), etc. Linear correlation was carried out on the abovementioned physical parameters, and the results revealed that, during corrosion, the correlation between compressive and tensile strength and mass (excluding Na2SO4 solution) is positive (mostly highly correlated), while that with wave velocity is poor (mostly moderately correlated). [ABSTRACT FROM AUTHOR]

Abstract: Desulfurization gypsum is the desulphurization products of wet FGD process in coal-fired power plants. However, it has not been widely used by far. In order to expand the application scope of desulphurization gypsum, desulphurization gypsum-industrial waste composite cementing material, a new type of hydraulic cementing material prepared by a lot of desulphurization gypsum, granulated blast furnace slag and some activator is studied in this paper. Its performance is also studied. [Copyright &y& Elsevier]

Tephra in glacial ice provide a method to obtain a depth vs chronology correlation within an ice core. Currently, core sections containing particulate must be sacrificially analysed to determine the nature of the particulate (e.g. aerosol, micrometeor, volcanic ash), and, in the case of volcanic ash, the event tied to the particle. Characterization through melting and chemical analysis precludes, de facto, its use for other purposes. A non-destructive technique to characterize particulates in ice cores prior to sectioning the samples, e.g. optical interrogation, would be useful, especially if chemical information specific to particular volcanic eruptions could be gleaned from such an analysis. We investigated the use of micro-Raman spectroscopy for this purpose. Spectra were obtained on samples of Antarctic blue ice tephra from different sources along with a reference ash sample of New Mexico Bandelier Tuff. Vitreous and crystalline particles in the samples were characterized. For vitreous material, a detailed analysis of the Raman-active vibrational bands of the glass structure was found to have the potential of being a unique identifier of the source of the glass, however, additional library development is needed for implementation. [ABSTRACT FROM AUTHOR]

Objectives: This study assesses the accuracy of the immediate blood separation method, a novel blood sampling strategy that enables blood analysis in any possible location. Methods: We conducted a cross-validation study between data from immediate blood separation and conventional methods. During the annual medical examinations in 2006 of a company located in an Osaka suburb, blood was drawn from workers ( n = 256; males 200, females 56) by puncturing their middle finger as well as venipuncture of the antecubital vein, by medical personnel. The following nine parameters were evaluated by autoanalyzer: aspartate aminotransferase (AST), alanine aminotransferase (ALT), γ-glutamyl transpeptidase (γGT), triglyceride, total cholesterol, high-density lipoprotein (HDL) cholesterol, urea nitrogen, uric acid, and creatinine. Results: After comparing data from the two methods using correlation analysis and regression analysis, we found a close R value (coefficient of determination) relationship that ranged from 0.996 to 1.000 for each item. The R value was 0.998 for Log AST, 0.997 for Log ALT, 0.999 for Log γGT, 1.000 for Log triglyceride, 1.000 for total cholesterol, 0.999 for HDL cholesterol, 0.998 for urea nitrogen, 0.999 for uric acid, and 0.996 for creatinine. Relationship was satisfactory for all nine items tested. Conclusion: Our results prove the reliability of data from the immediate blood separation method in an occupational health setting. The method enables self-testing by medically unskilled people, which is an important process to prevent lifestyle-related diseases. [ABSTRACT FROM AUTHOR]

The international trend of positioning the preschool as a pre-academic learning environment is challenging for preschool teachers, as it necessitates a balance between emotionally supportive interaction and goal-oriented learning instruction. However, previous research suggests that the complexities of such interactions need to be further studied. This article contributes by presenting a very detailed exploration of how social adaptation is pursued in a goal-oriented documentation activity. The study used a micro-sociological approach, characterized by the careful analysis of verbal and nonverbal interactions. Two research questions were raised: (1) How is social adaptation pursued in verbal and nonverbal interactions in preschool teacher–child relationships during a goal-oriented activity? and (2) How can social adaptation in the preschool context be understood in terms of a "deference-emotion system"? Interactions between a teacher and child in two video-recorded episodes were transcribed and sequentially analyzed thoroughly. The findings suggest that the interactions were regulated through an informal system of social sanctions, in which nonverbal signs of deference played a key role. The interaction was shown to be embedded in an institutional context that advocates goal-oriented instruction, thus highlighting the challenge of preschool teaching in attempting to promote goal-oriented processes while simultaneously maintaining respectful, caring teacher–child relationships. [ABSTRACT FROM AUTHOR]