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Volcanism is a fundamental process in the geological evolution of the Moon, providing clues to the composition and structure of the mantle, the location and duration of interior melting, the nature of convection and lunar thermal evolution. Progress in understanding volcanism has been remarkable in the short 60-year span of the Space Age. Before Sputnik 1 in 1957, the lunar farside was unknown, the origin of the dark lunar maria was debated (sedimentary or volcanic), and significant controversy surrounded the question of how the multitude of craters on the surface formed.

Importance: Atopic dermatitis onset usually occurs in childhood. Persistence of disease into adolescence and adulthood is common. It is important to evaluate new treatment options in adolescents because of the high unmet need in this population. Objective: To assess the efficacy and safety of upadacitinib to treat moderate-to-severe atopic dermatitis in adolescents. Design, Setting, and Participants: Prespecified analysis of adolescents enrolled in 3 randomized, double-blind, placebo-controlled phase 3 clinical trials in more than 20 countries across Europe, North and South America, Oceania, the Middle East, and the Asia-Pacific region from July 2018 through December 2020. Participants were adolescents aged 12 to 17 years with moderate-to-severe atopic dermatitis. Data analysis was performed from April to August 2021. Interventions: Patients were randomized (1:1:1) to once-daily oral upadacitinib 15 mg, upadacitinib 30 mg, or placebo alone (Measure Up 1 and Measure Up 2) or with topical corticosteroids (AD Up). Main Outcomes and Measures: Safety and efficacy, including at least a 75% improvement in the Eczema Area and Severity Index from baseline and validated Investigator Global Assessment for Atopic Dermatitis score of 0 (clear) or 1 (almost clear) at week 16 (coprimary end points). Results: A total of 552 adolescents (290 female; 262 male) were randomized. Mean (SD) age was 15.4 (1.8), 15.5 (1.7), and 15.3 (1.8) years for adolescents in Measure Up 1, Measure Up 2, and AD Up, respectively. In Measure Up 1, Measure Up 2, and AD Up, respectively, a greater proportion of adolescents (% [95% CI]) achieved at least 75% improvement in the Eczema Area and Severity Index at week 16 with upadacitinib 15 mg (73% [63%-84%], 69% [57%-81%], 63% [51%-76%]), and upadacitinib 30 mg (78% [68%-88%], 73% [62%-85%], 84% [75%-94%]), than with placebo (12% [4%-20%], 13% [5%-22%], 30% [19%-42%]; nominal P <.001 for all comparisons vs placebo). Similarly, a greater proportion of ad

Importance: Atopic dermatitis onset usually occurs in childhood. Persistence of disease into adolescence and adulthood is common. It is important to evaluate new treatment options in adolescents because of the high unmet need in this population. Objective: To assess the efficacy and safety of upadacitinib to treat moderate-to-severe atopic dermatitis in adolescents. Design, Setting, and Participants: Prespecified analysis of adolescents enrolled in 3 randomized, double-blind, placebo-controlled phase 3 clinical trials in more than 20 countries across Europe, North and South America, Oceania, the Middle East, and the Asia-Pacific region from July 2018 through December 2020. Participants were adolescents aged 12 to 17 years with moderate-to-severe atopic dermatitis. Data analysis was performed from April to August 2021. Interventions: Patients were randomized (1:1:1) to once-daily oral upadacitinib 15 mg, upadacitinib 30 mg, or placebo alone (Measure Up 1 and Measure Up 2) or with topical corticosteroids (AD Up). Main Outcomes and Measures: Safety and efficacy, including at least a 75% improvement in the Eczema Area and Severity Index from baseline and validated Investigator Global Assessment for Atopic Dermatitis score of 0 (clear) or 1 (almost clear) at week 16 (coprimary end points). Results: A total of 552 adolescents (290 female; 262 male) were randomized. Mean (SD) age was 15.4 (1.8), 15.5 (1.7), and 15.3 (1.8) years for adolescents in Measure Up 1, Measure Up 2, and AD Up, respectively. In Measure Up 1, Measure Up 2, and AD Up, respectively, a greater proportion of adolescents (% [95% CI]) achieved at least 75% improvement in the Eczema Area and Severity Index at week 16 with upadacitinib 15 mg (73% [63%-84%], 69% [57%-81%], 63% [51%-76%]), and upadacitinib 30 mg (78% [68%-88%], 73% [62%-85%], 84% [75%-94%]), than with placebo (12% [4%-20%], 13% [5%-22%], 30% [19%-42%]; nominal P <.001 for all comparisons vs placebo). Similarly, a greater proportion of ad

Weathering of basalt in tropical environments is sensitive to climate change and considered to play a significant role in regulating climate evolution. Though extensively studied on the modern Earth and hypothesized for the geological past, basalt weathering is difficult to directly track in geological archives. We here focus on the basaltic sediments derived from the Emeishan large igneous province (LIP) in South China and determined their organic carbon content and isotope, mineral and geochemical compositions. Based on the newly obtained high-precision zircon U-Pb age of 251.79 ± 0.12/0.13/0.36 Ma, we establish temporal variations of weathering intensity for the Emeishan LIP basaltic landscapes in the tropical latitudes through the Permo-Triassic rapid climate warming periods. Analysis of weathering trends indicates a significant decrease in weathering intensity across the Permo-Triassic transition. This decrease in intensity is anomalous considering its coincidence with the climate warming at the Permo-Triassic transition, which tends to elevate chemical weathering rate of basalts and produce sediments with high chemical weathering intensity. Combining these weathering trends with present-day basalt weathering-temperature relationship and reported paleo-temperatures, total erosion rate is quantitatively estimated to increase from 282 ± 43 t/km2/yr in the latest Permian to > 1618 ± 187 t/km2/yr in the Early Triassic. This massive erosion in the Early Triassic is plausibly related to amplified extreme precipitation associated with intensification of the hydrological cycle in the Early Triassic hothouse climate. This study underlines the weathering responses of tropical landscapes to rapid climate warming.

Weathering of basalt in tropical environments is sensitive to climate change and considered to play a significant role in regulating climate evolution. Though extensively studied on the modern Earth and hypothesized for the geological past, basalt weathering is difficult to directly track in geological archives. We here focus on the basaltic sediments derived from the Emeishan large igneous province (LIP) in South China and determined their organic carbon content and isotope, mineral and geochemical compositions. Based on the newly obtained high-precision zircon U-Pb age of 251.79 ± 0.12/0.13/0.36 Ma, we establish temporal variations of weathering intensity for the Emeishan LIP basaltic landscapes in the tropical latitudes through the Permo-Triassic rapid climate warming periods. Analysis of weathering trends indicates a significant decrease in weathering intensity across the Permo-Triassic transition. This decrease in intensity is anomalous considering its coincidence with the climate warming at the Permo-Triassic transition, which tends to elevate chemical weathering rate of basalts and produce sediments with high chemical weathering intensity. Combining these weathering trends with present-day basalt weathering-temperature relationship and reported paleo-temperatures, total erosion rate is quantitatively estimated to increase from 282 ± 43 t/km2/yr in the latest Permian to > 1618 ± 187 t/km2/yr in the Early Triassic. This massive erosion in the Early Triassic is plausibly related to amplified extreme precipitation associated with intensification of the hydrological cycle in the Early Triassic hothouse climate. This study underlines the weathering responses of tropical landscapes to rapid climate warming.

The parameter equations of circle, Elliptic and arbitrary polymorphic were deduced by polar coordinates transformation in this paper, and a 2D reconstruction method of irregular particles based on cellular automata theory was introduced, briefly. The particles size and quantity information could be automatic computed by a sectional calculate and residual accumulation algorithm which was developed in this paper. The computed particles size and quantity information had a good agreement with the aggregate actual sieving curve. The corresponding dynamic packing model of 2D fully-graded arbitrary shaped concrete aggregate was further developed, and all kinds arbitrary shaped particles systems' limit accumulation states could be obtained by setting appropriate parameters. The limit packing density of circle particles system was the biggest, up to 79.59%.

The parameter equations of circle, Elliptic and arbitrary polymorphic were deduced by polar coordinates transformation in this paper, and a 2D reconstruction method of irregular particles based on cellular automata theory was introduced, briefly. The particles size and quantity information could be automatic computed by a sectional calculate and residual accumulation algorithm which was developed in this paper. The computed particles size and quantity information had a good agreement with the aggregate actual sieving curve. The corresponding dynamic packing model of 2D fully-graded arbitrary shaped concrete aggregate was further developed, and all kinds arbitrary shaped particles systems' limit accumulation states could be obtained by setting appropriate parameters. The limit packing density of circle particles system was the biggest, up to 79.59%.

Fuzzing is a technique widely used in vulnerability detection. The process usually involves writing effective fuzz driver programs, which, when done manually, can be extremely labor intensive. Previous attempts at automation leave much to be desired, in either degree of automation or quality of output. In this paper, we propose IntelliGen, a framework that constructs valid fuzz drivers automatically. First, IntelliGen determines a set of entry functions and evaluates their respective chance of exhibiting a vulnerability. Then, IntelliGen generates fuzz drivers for the entry functions through hierarchical parameter replacement and type inference. We implemented IntelliGen and evaluated its effectiveness on real-world programs selected from the Android Open-Source Project, Google's fuzzer-test-suite and industrial collaborators. IntelliGen covered on average 1.08X-2.03X more basic blocks and 1.36X-2.06X more paths over state-of-the-art fuzz driver synthesizers FUDGE and FuzzGen. IntelliGen performed on par with manually written drivers and found 10 more bugs., Comment: 10 pages, 5 figures

Accurate prediction of the stability of rock surrounding a tunnel is important in order to prevent from rock collapse or reduce the hazard to personnel and traffic caused by such incidents. In our study, a KNN algorithm based on grouped center vector is proposed, which reduces the complexity of calculation, thus improving the prediction performance of the algorithm. Then, the improved KNN algorithm was applied to the surrounding rock stability prediction of a high-speed railway tunnel, which, to our knowledge, forms the first application thereof for the prediction of surrounding rock stability. Extensive experimental results show that our proposed prediction model achieves high prediction performance in this regard. Finally, a laboratory experiment of a tunnel is conducted to evaluate whether the tunnel surrounding rock is stable or not. The experimental results matched the prediction results obtained by our proposed prediction model, which further demonstrates its effectiveness.

Greybox fuzzing has made impressive progress in recent years, evolving from heuristics-based random mutation to approaches for solving individual path constraints. However, they have difficulty solving path constraints that involve deeply nested conditional statements, which are common in image and video decoders, network packet analyzers, and checksum tools. We propose an approach for addressing this problem. First, we identify all the control flow-dependent conditional statements of the target conditional statement. Next, we select the data flow-dependent conditional statements. Finally, we use three strategies to find an input that satisfies all conditional statements simultaneously. We implemented this approach in a tool called Matryoshka and compared its effectiveness on 13 open source programs against other state-of-the-art fuzzers. Matryoshka found significantly more unique crashes than AFL, QSYM, and Angora. We manually classified those crashes into 41 unique new bugs, and obtained 12 CVEs. Our evaluation also uncovered the key technique contributing to Matryoshka's impressive performance: it collects only the nesting constraints that may cause the target conditional statements unreachable, which greatly simplifies the constraints that it has to solve.

The last glaciation during the late Paleozoic ice age commenced at around the Guadalupian–Lopingian (G–L) boundary and is synchronous with the emplacement of the Emeishan large igneous province. Using CA-TIMS zircon U–Pb dating, we obtained an age of 259.51 ± 0.21 Ma for the uppermost tuff from the Puan volcanic sequence in the eastern Emeishan large igneous province, constraining the timing of Emeishan volcanism and providing another candidate age for the G–L boundary. In addition, we determined an age of 259.69 ± 0.72 Ma for a basal claystone in the immediately overlying Longtan Formation from a drill core section in southwest South China. These ages, along with source weathering trends of mudstones from the lower Longtan Formation, and compiled paleotemperature records, indicate an earliest Wuchiapingian cooling coinciding with the onset of the last Permian glaciation. This global cooling is associated with positive shifts in both organic and carbonate carbon isotopic records and likely a decrease in atmospheric pCO2. A hypothesised causal linkage is proposed in which the rapid post-eruptive basaltic weathering of the Emeishan province in an equatorial humid belt may accelerate the atmospheric CO2 consumption and lead to climate cooling. Our work supports the long-term climate cooling effects of large igneous provinces.

The last glaciation during the late Paleozoic ice age commenced at around the Guadalupian–Lopingian (G–L) boundary and is synchronous with the emplacement of the Emeishan large igneous province. Using CA-TIMS zircon U–Pb dating, we obtained an age of 259.51 ± 0.21 Ma for the uppermost tuff from the Puan volcanic sequence in the eastern Emeishan large igneous province, constraining the timing of Emeishan volcanism and providing another candidate age for the G–L boundary. In addition, we determined an age of 259.69 ± 0.72 Ma for a basal claystone in the immediately overlying Longtan Formation from a drill core section in southwest South China. These ages, along with source weathering trends of mudstones from the lower Longtan Formation, and compiled paleotemperature records, indicate an earliest Wuchiapingian cooling coinciding with the onset of the last Permian glaciation. This global cooling is associated with positive shifts in both organic and carbonate carbon isotopic records and likely a decrease in atmospheric pCO2. A hypothesised causal linkage is proposed in which the rapid post-eruptive basaltic weathering of the Emeishan province in an equatorial humid belt may accelerate the atmospheric CO2 consumption and lead to climate cooling. Our work supports the long-term climate cooling effects of large igneous provinces.

OBJECTIVE: To investigate the inhibitory effects of cisplatin combined with HMME-based photodynamic therapy (PDT) on human nasopharyngeal carcinoma cell lines (CNE-2) in vitro. METHODS: The experimental cells were divided into control group, PDT only group, DDP only group and combined treatment group. 0.8 and 1.6 mg/L cisplatin were used to treat cells. The dose of HMME was 5 mg/L, the light doses were 1.2, 2.4 and 4.8 J/cm2. The inhibitory effects caused by the two treatments (cisplatin, HMME-PDT) administered individually and together were evaluated by MTT. Jin's equation was used to evaluate the efficacy of drug combination. The morphological character 24 h post-treatment was examined by HE and Hoechst staining. RESULTS: Jin's equation showed that 0.5 and 1.6 mg/L cisplatin combined with 5 mg/L HMME under 1.2, 2.4 and 4.8 J/cm2 energy dosage demonstrated additive or synergic effect. HE and Hoechst33342 stainning exhibited more obvious morphologic alterations in combined treatment group when compared to DDP and PDT group. CONCLUSION: Our study suggests that cisplatin combined with PDT has a significant synergistic inhibitory effect on CNE-2 cells in a certain range.

OBJECTIVE: To investigate the inhibitory effects of cisplatin combined with HMME-based photodynamic therapy (PDT) on human nasopharyngeal carcinoma cell lines (CNE-2) in vitro. METHODS: The experimental cells were divided into control group, PDT only group, DDP only group and combined treatment group. 0.8 and 1.6 mg/L cisplatin were used to treat cells. The dose of HMME was 5 mg/L, the light doses were 1.2, 2.4 and 4.8 J/cm2. The inhibitory effects caused by the two treatments (cisplatin, HMME-PDT) administered individually and together were evaluated by MTT. Jin's equation was used to evaluate the efficacy of drug combination. The morphological character 24 h post-treatment was examined by HE and Hoechst staining. RESULTS: Jin's equation showed that 0.5 and 1.6 mg/L cisplatin combined with 5 mg/L HMME under 1.2, 2.4 and 4.8 J/cm2 energy dosage demonstrated additive or synergic effect. HE and Hoechst33342 stainning exhibited more obvious morphologic alterations in combined treatment group when compared to DDP and PDT group. CONCLUSION: Our study suggests that cisplatin combined with PDT has a significant synergistic inhibitory effect on CNE-2 cells in a certain range.

OBJECTIVE: To investigate the inhibitory effects of cisplatin combined with HMME-based photodynamic therapy (PDT) on human nasopharyngeal carcinoma cell lines (CNE-2) in vitro. METHODS: The experimental cells were divided into control group, PDT only group, DDP only group and combined treatment group. 0.8 and 1.6 mg/L cisplatin were used to treat cells. The dose of HMME was 5 mg/L, the light doses were 1.2, 2.4 and 4.8 J/cm2. The inhibitory effects caused by the two treatments (cisplatin, HMME-PDT) administered individually and together were evaluated by MTT. Jin's equation was used to evaluate the efficacy of drug combination. The morphological character 24 h post-treatment was examined by HE and Hoechst staining. RESULTS: Jin's equation showed that 0.5 and 1.6 mg/L cisplatin combined with 5 mg/L HMME under 1.2, 2.4 and 4.8 J/cm2 energy dosage demonstrated additive or synergic effect. HE and Hoechst33342 stainning exhibited more obvious morphologic alterations in combined treatment group when compared to DDP and PDT group. CONCLUSION: Our study suggests that cisplatin combined with PDT has a significant synergistic inhibitory effect on CNE-2 cells in a certain range.

Objective To study the effects of HMME-based photodynamic therapy on proliferation and apoptosis of rabbit vascular smooth muscle cells(VSMCs). Method The cytotoxic effect of HMME-PDT on rabbit vascular smooth muscle cells was studied by means of Trypan Blue assay, HMME at 10μg/ml concentration and the light dose at 2.4-4.8 J/cm2 were selected in the studies. The morphological character 24h post-PDT was investigated by HE Staining. Annexin V and propidium iodide (PI) binding assays were performed to analyze the characteristics of cell death after HMME-PDT. Furthermore, The intracellular distributions of the HMME were measured by the confocal laser scanning microscope. Result It was showed the photocytotoxity to VSMC cells was dose related by Trypan Blue assay. Histology observing suggests HMME-PDT could induce cell death through apoptosis or necrosis, and the apoptosic rate was up to 50.5% by AnnexinV/PI assay. Moreover, the fluorescence images of HMME intracellular localization demonstrated that the HMME diffused into the mitochondria. Conclusion HMME-PDT could significantly inhibite VSMC proliferation and induce apoptosis.

Oxidative stress plays a substantial role in the genesis of noise-reduced cochlear injury that causes permanent hearing loss. We present the results of three different approaches to enhance intrinsic cochlear defense mechanism against oxidative stress. This article explores, through the following set of hypotheses, some of the postulated causes of noise-induced cochlear oxidative stress (NICOS) and how noise-induced cochlear damage may be reduced pharmacologically. 1) NICOS is in part related to defects in mitochondrial bioenergetics and biogenesis. Therefore, NICOS can be reduced by acetyl-L carnitine (ALCAR), an endogenous mitochondrial membrane compound that helps maintain mitochondrial bioenergetics and biogenesis in the face of oxidative stress. 2) A contributing factor in NICOS injury is glutamate excitotoxicity, which can be reduced by antagonizing the action of cochlear N-methyl-D-aspartate (NMDA) receptors using carbamathione, which acts as a glutamate antagonist. 3) Noise-induced hearing loss (NIHL) may be characterized as a cochlear-reduced glutathione (GSH) deficiency state; therefore, strategies to enhance cochlear GSH levels may reduce noise-induced cochlear injury. The objective of this study was to document the reduction in noise-induced hearing and hair cell loss, following application of ALCAR, carbamathione, and a GSH repletion drug D-methionine (MET), to a model of noise-induced hearing loss., Published in The Laryngoscope, v112 p1515-1532, September 2002. Sponsored in part by the United States Army Medical Research and Material Command, Fort Detrick, MD.

Three complexes, namely [Cd(tren)][Fe(CN)(5)NO] (2), [Cd(tren)][Pd(CN)(4)] (3) and [Cd(tren)][Pt(CN)(6)] (4), were prepared via direct reactions of Na-2[Fe(CN)(5)NO], K-2[Pd(CN)(4)] and K-2[Pt(CN)(6)], respectively, with cadmium acetate and tris(2-aminoethyl)amine (tren) in aqueous solution. X-ray structural analysis shows that 2 features a shelf-like structure formed by stacking of the quasi-square building block. Compound 3 is a battlement-like polymer constructed from cyanometalate building blocks and compound 4 represents the first example of a cyano-bridged trinuclear hexacyanoplatinate(IV) complex.

Three complexes, namely [Cd(tren)][Fe(CN)(5)NO] (2), [Cd(tren)][Pd(CN)(4)] (3) and [Cd(tren)][Pt(CN)(6)] (4), were prepared via direct reactions of Na-2[Fe(CN)(5)NO], K-2[Pd(CN)(4)] and K-2[Pt(CN)(6)], respectively, with cadmium acetate and tris(2-aminoethyl)amine (tren) in aqueous solution. X-ray structural analysis shows that 2 features a shelf-like structure formed by stacking of the quasi-square building block. Compound 3 is a battlement-like polymer constructed from cyanometalate building blocks and compound 4 represents the first example of a cyano-bridged trinuclear hexacyanoplatinate(IV) complex.

Three complexes, namely [Cd(tren)][Fe(CN)(5)NO] (2), [Cd(tren)][Pd(CN)(4)] (3) and [Cd(tren)][Pt(CN)(6)] (4), were prepared via direct reactions of Na-2[Fe(CN)(5)NO], K-2[Pd(CN)(4)] and K-2[Pt(CN)(6)], respectively, with cadmium acetate and tris(2-aminoethyl)amine (tren) in aqueous solution. X-ray structural analysis shows that 2 features a shelf-like structure formed by stacking of the quasi-square building block. Compound 3 is a battlement-like polymer constructed from cyanometalate building blocks and compound 4 represents the first example of a cyano-bridged trinuclear hexacyanoplatinate(IV) complex.

The reaction of AgNO3 with tris(2-aminoethyl)amine (tren) affords an unusual achiral grid with desirable chiral channels [Ag(tren)]NO3 (1), and a species of single-stranded helical polymer, [Ag(baep)]NO3. MeOH (2), baep = 1,4-bis(2-aminoethyl)-piperazine, which indicates that the polyamine ligand tren is converted during the process of the reaction.

The reaction of AgNO3 with tris(2-aminoethyl)amine (tren) affords an unusual achiral grid with desirable chiral channels [Ag(tren)]NO3 (1), and a species of single-stranded helical polymer, [Ag(baep)]NO3. MeOH (2), baep = 1,4-bis(2-aminoethyl)-piperazine, which indicates that the polyamine ligand tren is converted during the process of the reaction.

The reaction of AgNO3 with tris(2-aminoethyl)amine (tren) affords an unusual achiral grid with desirable chiral channels [Ag(tren)]NO3 (1), and a species of single-stranded helical polymer, [Ag(baep)]NO3. MeOH (2), baep = 1,4-bis(2-aminoethyl)-piperazine, which indicates that the polyamine ligand tren is converted during the process of the reaction.

A study is presented of the upgrading of five lignites, obtained from typical coal-producing areas - Bai Yinhua (BYH), Dong Wuqi (DWQ), Meng Yuan (MY), Gu Shan (GS) and Shan Gu (SG) - of Inner Mongolia, China, by microwave irradiation to increase their slurryabilities for applications in coal-water-slurry fuels. The chemical and physical properties of the microwave-irradiated lignites are investigated using proximate and ultimate analyses, Fourier-transform infrared spectroscopy, zeta potential determinations, contact angle measurements and nitrogen adsorption porosimetry. The results indicate that, following microwave irradiation, the oxygen functional groups and oxygen:carbon ratios decrease in the five lignites. The zeta potentials of the BYH, MY, GS and SG lignites and the contact angles of the five lignites increase after microwave irradiation, while the specific surface areas of the MY, BYH, GS and DWQ lignites decrease. The maximum solid concentrations of the coal-water-slurries (viscosity 1 000 mPa.s; shear rate 100/s) prepared from the GS, BYH, MY, DWQ and SG lignites increase from 55.8, 47.3, 46.2, 46.1 and 42.6%, respectively, to 59.8, 57.2, 52.0, 51.9 and 50.3%, respectively, following microwave treatment., A study is presented of the upgrading of five lignites, obtained from typical coal-producing areas - Bai Yinhua (BYH), Dong Wuqi (DWQ), Meng Yuan (MY), Gu Shan (GS) and Shan Gu (SG) - of Inner Mongolia, China, by microwave irradiation to increase their slurryabilities for applications in coal-water-slurry fuels. The chemical and physical properties of the microwave-irradiated lignites are investigated using proximate and ultimate analyses, Fourier-transform infrared spectroscopy, zeta potential determinations, contact angle measurements and nitrogen adsorption porosimetry. The results indicate that, following microwave irradiation, the oxygen functional groups and oxygen:carbon ratios decrease in the five lignites. The zeta potentials of the BYH, MY, GS and SG lignites and the contact angles of the five lignites increase after microwave irradiation, while the specific surface areas of the MY, BYH, GS and DWQ lignites decrease. The maximum solid concentrations of the coal-water-slurries (viscosity 1 000 mPa.s; shear rate 100/s) prepared from the GS, BYH, MY, DWQ and SG lignites increase from 55.8, 47.3, 46.2, 46.1 and 42.6%, respectively, to 59.8, 57.2, 52.0, 51.9 and 50.3%, respectively, following microwave treatment.

This work studied the influence of quartz mill tailings on the properties of a geopolymer based on alkali-activated metakaolin. Performance of the geopolymer incorporated with quartz mill tailings were addressed in terms of workability, compressive and flexural strength, and drying shrinkage at different ages. Further, X-ray Diffraction, Scanning Electron Microscopy (SEM), Fourier Transform Infrared Spectroscopy (FTIR) and Mercury Intrusion Porosimetry (MIP) were applied to investigate the relevant microstructure. Results indicated that addition of quartz mill tailings increased the viscosity of the paste and decreased the flowability of geopolymer. Up to 20% of the tailings can replace metakaolin to prepare a geopolymer without negative effect on the mechanical properties. Up to 30% of quartz mill tailings had a role in decreasing the drying shrinkage. Besides, weight loss ratio of the geopolymer decreased gradually with increasing dosage of the quartz mill tailings. MIP and FTIR results showed that moderate addition of quartz mill tailings optimised the microstructure of the geopolymer. Therefore, quartz mill tailings can replace metakaolin up to 20% to prepare a geopolymer., This work studied the influence of quartz mill tailings on the properties of a geopolymer based on alkali-activated metakaolin. Performance of the geopolymer incorporated with quartz mill tailings were addressed in terms of workability, compressive and flexural strength, and drying shrinkage at different ages. Further, X-ray Diffraction, Scanning Electron Microscopy (SEM), Fourier Transform Infrared Spectroscopy (FTIR) and Mercury Intrusion Porosimetry (MIP) were applied to investigate the relevant microstructure. Results indicated that addition of quartz mill tailings increased the viscosity of the paste and decreased the flowability of geopolymer. Up to 20% of the tailings can replace metakaolin to prepare a geopolymer without negative effect on the mechanical properties. Up to 30% of quartz mill tailings had a role in decreasing the drying shrinkage. Besides, weight loss ratio of the geopolymer decreased gradually with increasing dosage of the quartz mill tailings. MIP and FTIR results showed that moderate addition of quartz mill tailings optimised the microstructure of the geopolymer. Therefore, quartz mill tailings can replace metakaolin up to 20% to prepare a geopolymer.