To study the relationship between material composition, curing conditions and strength development, the study simulated high-strength precast concrete pile production, and a high-strength mortar up to 90 MPa was desig...To study the relationship between material composition, curing conditions and strength development, the study simulated high-strength precast concrete pile production, and a high-strength mortar up to 90 MPa was designed and a hot-water pool was built for concrete curing. The major point of the study was to achieve a high early strength by using cement/metakaolin systems without autoclave curing with high-pressure steam. By means of XRD and thermal analysis, the progress of the hydration of the cement pastes blended with metakaolin was characterized. The main results indicate that high strength can be obtained at early age by the use of metakaolin and thermal treatment （hot-water curing）. The improvement in strength of mortars with metakaolin can be explained by an increase in the amount of C-S-H and C-S-A-H hydrated phases and a decrease in the amount of calcium hydration（CH）. Further more, a decrease in Ca/Si ratio of the matrix was observed from the results of EDX analysis, which also leaded to an improvement of the compressive strength. These results are of great importance for the high-strength precast concrete manufacturing industry.展开更多
Four layers of cherts were found for the first time in the Yangla copper deposit, western Yunnan Province. The cherts possessed the following geochemical characteristics: 1 Low TiO2 and Al2O3 contents, but high ore-fo...Four layers of cherts were found for the first time in the Yangla copper deposit, western Yunnan Province. The cherts possessed the following geochemical characteristics: 1 Low TiO2 and Al2O3 contents, but high ore-forming element (e.g. Cu, Au, Ag) contents; 2 low total REE contents and clear negative Eu anomalies when normalized to chondrite similar to the REE contents and distribution patterns of associated massive sulfide ores; 3 silicon isotopic compositions of cherts in the Yangla deposit being the same as cherts and geyserite of hot-water sedimentary origin; 4 lead and sulfur isotopic compositions of cherts in the Yangla deposit being similar to those of the massive sulfide ores in the Yangla deposit; 5 Rb-Sr isochron age of cherts from the Yangla deposit being identical with that of host strata. Hence, we conclude that the cherts in the Yangla deposit are of hot-water sedimentary origin, which have a close relationship with the massive sulfide ores. The discovery of hydrothermal cherts from the Yangla copper deposit provides further evidence for the hydrothermal exhalative origin of the massive sulfide deposits.展开更多
Investigating the effects of residue chemical composition on soil labile organic carbon （LOC） will improve our understanding of soil carbon sequestration. The effects of maize residue chemical composition and soil w...Investigating the effects of residue chemical composition on soil labile organic carbon （LOC） will improve our understanding of soil carbon sequestration. The effects of maize residue chemical composition and soil water content on soil LOC fractions and microbial properties were investigated in a laboratory incubation experiment. Maize shoot and root residues were incorporated into soil at 40% and 70% field capacity. The soils were incubated at 20 ℃ for 150 d and destructive sampling was conducted after 15, 75, and 150 d. Respiration, dissolved organic carbon （DOC）, hot-water extractable organic carbon （HEOC）, and microbial biomass carbon （MBC） were recorded, along with cellulase and β-glucosidase activities and community-level physiological profiles. The results showed that the cumulative respiration was lower in root-amended soils than in shoot-amended soils, indicating that root amendment may be beneficial to C retention in soil. No significant differences in the contents of DOG, HEOC and MBC, enzyme activities, and microbial functional diversity were observed between shoot- and root-amended soils. The high soil water content treatment significantly increased the cumulative respiration, DOC and HEOC contents, and enzyme activities compared to the low soil water content treatment. However, the soil water content treatments had little influence on the MBC content and microbial functional diversity. There were significantly positive correlations between LOC fractions and soil microbial properties. These results indicated that the chemical composition of maize residues had little influence on the DOC, HEOC, and MBC contents, enzyme activities, and microbial functional diversity, while soil water content could significantly influence DOC and HEOC contents and enzyme activities.展开更多
The study was conducted in Zhifanggou Watershed,Shaanxi Province,China,to evaluate the effect of different vegetation types on hot-water extractable C,N and P fractions,with the aim to determine whether hot-water extr...The study was conducted in Zhifanggou Watershed,Shaanxi Province,China,to evaluate the effect of different vegetation types on hot-water extractable C,N and P fractions,with the aim to determine whether hot-water extractable fractions could be used as indicators of soil quality change in Loess Plateau.The six vegetation types established in 1975 were（i） Robinia pseudoacacia L.,（ii） Caragana korshinkii Kom.,（iii） Pinus tabulaeformis Carr.,（iv） P.tabulaeformis-Amorpha fruticosa L.,（v） R.pseudoacacia-A.fruticosa,and（vi） grassland.A cropped hillslope plot and a Platycladus orientalis L.native forest plot were used as references.The results indicated that the conversion of native forest to cropland resulted in a significant decline in the hot-water extractable C,N and P fractions.Hot-water extractable C,N,and P increased when cultivated land was revegetated,but after 30 years the amount of hot-water extractable C,N,and P in revegetated fields was still much lower compared to native forest.Hot-water extractable fractions increased more under mixed-forest than under pure-forest stands.Furthermore,there was a significant correlation between the hot-water extractable fractions and soil chemical and microbiological properties.The results showed that hot-water extractable fractions could be used as indicators of soil quality change on the Loess Plateau.展开更多
Although the importance to global oceanography of ice shelf-oceaaa interactions has been recognized for many years, only more recently has its role in the control of ice flow- from the interior, grounded ice sheet int...Although the importance to global oceanography of ice shelf-oceaaa interactions has been recognized for many years, only more recently has its role in the control of ice flow- from the interior, grounded ice sheet into the ocean been more clearly understood. The consequences for global sea level of increasing ice loss from the Antarctic and Greenland ice sheets has prompted rapidly growing research efforts in this area. Here we describe the different techniques commonly employed in the field study of ice shelf-ocean interactions. We focus on techniques used by the British Antarctic Survey, primarily on Filchner-Ronne Ice Shelf, and describe some recent results from instruments deployed both beneath the ice shelf and on its upper surface, which demonstrate variability at a broad range of time scales.展开更多
Objective: To investigate the fungistatic activity and synergistic effects of natural products and their constituents, including traditional oriental medicines(TOMs).Methods: Fungistatic activities of TOMs prepared by...Objective: To investigate the fungistatic activity and synergistic effects of natural products and their constituents, including traditional oriental medicines(TOMs).Methods: Fungistatic activities of TOMs prepared by hot-water(115 ℃) or ethanol(70%; 40 ℃) extraction were determined by their minimum inhibitory concentration.To assess possible synergistic effects, minimum inhibitory concentrations of various combinations were evaluated.Results: By evaluating antifungal susceptibility of Trichophyton rubrum, which is a major causative fungus for several types of dermatophytosis, we confirmed that ethanol extracts were more active than hot-water extracts in 25 of the 36 TOMs, suggesting that the constituents with high hydrophobicity tend to contribute significantly to fungistatic activity.We selected four TOMs with high fungistatic activity, including Aucklandiae radix, Gentianae macrophyllae radix, Scutellariae radix, and Galla rhois, and their synergistic effects were investigated through the combination studies between TOMs or TOM-conventional drug terbinafine.In combinations between four TOMs, partial synergistic effects were observed in Aucklandiae radix–Galla rhois and Gentianae macrophyllae radix–Galla rhois combinations, as supported by the lowest fractional inhibitory concentration index value of 0.66 for both combinations.Furthermore, Galla rhois showed the strongest synergistic effect on growth inhibition of Trichophyton rubrumwith a fractional inhibitory concentration index value of 0.50 in combination with terbinafine.Conclusions: Our findings indicate that the combination of TOMs and TOM-terbinafine may be effective on treatment for chronic and recurrent dermatophytosis by improving fungistatic activity and led to decrease systemic toxicity in clinical practice.展开更多
In this study, effects of hot water extract of Paecilomyces hepiali mycelia on hypertension parameters in spontaneously hypertensive rats (SHR) were investigated. The tested parameters included blood pressure, blood a...In this study, effects of hot water extract of Paecilomyces hepiali mycelia on hypertension parameters in spontaneously hypertensive rats (SHR) were investigated. The tested parameters included blood pressure, blood and urine biochemical composition, renin and angiotensin II levels in the blood. Prior to these tests, the extract was examined for toxicity. The fungus was cultivated in a solid medium composed of 40 g brown rice, 0.32 g glucose, 0.65 g sucrose, 2 g peptone and 65 ml corn steep liquor. No abnormality or harmful effects were observed in the toxicity test. Administration of a continuous-dose, once daily, to SHR for 27 weeks (from 13 weeks of age) decreased the systolic blood pressure (SBP) significantly. Levels of blood urea nitrogen, β-lipoprotein lipid peroxides and low density lipoprotein were significantly lower in the treated groups when compared to the control group. Urinary protein was significantly reduced in the middle and high dose groups. In comparison with the control group (0 mg/kg/10ml/day), significantly higher values were obtained for total cholesterol in groups that were given middle (170 mg/kg/10ml/day) and high (250 mg/kg/10ml/day) dosages. In all dosages (low, middle and high) the values for triglyceride were significantly higher than value found in the control group. In terms of angiotensin II levels, the value in the control group was markedly higher than values in the other groups. The results suggest that oral administration of hot water extract of P. hepiali mycelia has ability to control hypertension in rats.展开更多
Objective:To examine the immune responses of Litopenaeus vannamei after different treatments with a hot water extract of Macrocystis pyrifera(M.pyrifera)and a subsequent challenge with Vibrio campbellii(V.campbellii)....Objective:To examine the immune responses of Litopenaeus vannamei after different treatments with a hot water extract of Macrocystis pyrifera(M.pyrifera)and a subsequent challenge with Vibrio campbellii(V.campbellii).Methods:A total of 184 adult white shrimp that were infected with V.campbellii(1×10^(6) CFU/shrimp)were immunostimulate by the hot-water extract from M.pyrifera via either injection(10μg)or immersion(350 mg/L),the experimental controls were injected with either saline solution or V.campbellii(1×10^(6) CFU/shrimp).The bacterial DNA depuration rate,antimicrobial activity and total hemocyte count were evaluated in hemolymph samples at 2,6,12,24,48 and 72 h post-infection.Results:Injected shrimp(10μg M.pyrifera extract)demonstrated the best clearance of bacterial infection,with 82%survival at 72 h post-infection(cellular response).Hemolymph from the immersed organisms had the best antimicrobial activity against Escherichia coli growth;specifically,the most efficient antimicrobial activity was observed at 24 h post-infection.Both types of immunostimulated shrimp had similar total hemocyte counts at 24 h post-infection(1.63-1.59 million/mL);however,after 72 h,injected shrimp had higher total hemocyte counts than immersed animals(2.59 v.s.0.56 million/mL).Conclusions:The injection of the M.pyrifera hot-water extract facilitated a more efficient response to V.campbellii infection due to the stimulation of the hemocytes of the shrimp.In other words,the cellular immune response was more efficient to eliminate bacterial infection than the humoral response in shrimp.展开更多
Combined cooling,heating and power(CCHP)systems are characterized by a substantially higher energy-utilization efficiency compared to standalone systems.In this study,an integrated system comprising a solid-oxide fuel...Combined cooling,heating and power(CCHP)systems are characterized by a substantially higher energy-utilization efficiency compared to standalone systems.In this study,an integrated system comprising a solid-oxide fuel cell(SOFC),hot-water storage tank(HWST)and absorption refrigeration(AR)cycle is considered.The SOFC model was developed in Aspen Plus®.It was used to determine the thermodynamic properties of the exhaust gas that was then used to provide heat for the HWST and to drive the AR cycle.Thermodynamic models for the AR cycles were developed in Engineering Equation Solver,considering LiBr-H2O and NH3-H2O as working fluids.The sensitivity analysis of a number of SOFC output parameters has been carried out.The most optimal case was characterized with the coefficient of performance(COP)and CCHP efficiency of 0.806 and 85.2%for the LiBr-H2O system,and 0.649 and 83.6%for the NH3-H2O system,respectively.Under such optimal operating conditions,the SOFC was characterized by the net electrical efficiency of 57.5%and the net power output of 123.66 kW.Data from the optimal solution were used to perform the thermodynamic study and sensitivity analysis to assess the influence of different absorption cycle operating conditions and to identify possible applications for the considered integrated systems.展开更多
基金Funded by the National Fundamental Scientific Research Project of China(2009CB623201)
文摘To study the relationship between material composition, curing conditions and strength development, the study simulated high-strength precast concrete pile production, and a high-strength mortar up to 90 MPa was designed and a hot-water pool was built for concrete curing. The major point of the study was to achieve a high early strength by using cement/metakaolin systems without autoclave curing with high-pressure steam. By means of XRD and thermal analysis, the progress of the hydration of the cement pastes blended with metakaolin was characterized. The main results indicate that high strength can be obtained at early age by the use of metakaolin and thermal treatment （hot-water curing）. The improvement in strength of mortars with metakaolin can be explained by an increase in the amount of C-S-H and C-S-A-H hydrated phases and a decrease in the amount of calcium hydration（CH）. Further more, a decrease in Ca/Si ratio of the matrix was observed from the results of EDX analysis, which also leaded to an improvement of the compressive strength. These results are of great importance for the high-strength precast concrete manufacturing industry.
基金This work was jointly supported by key project of Chinese Academy of Sciences (KZ952-S1-407) state Key Project of China (G1999043208 and 1999043210) China Postdoctoral Science Foundation.
文摘Four layers of cherts were found for the first time in the Yangla copper deposit, western Yunnan Province. The cherts possessed the following geochemical characteristics: 1 Low TiO2 and Al2O3 contents, but high ore-forming element (e.g. Cu, Au, Ag) contents; 2 low total REE contents and clear negative Eu anomalies when normalized to chondrite similar to the REE contents and distribution patterns of associated massive sulfide ores; 3 silicon isotopic compositions of cherts in the Yangla deposit being the same as cherts and geyserite of hot-water sedimentary origin; 4 lead and sulfur isotopic compositions of cherts in the Yangla deposit being similar to those of the massive sulfide ores in the Yangla deposit; 5 Rb-Sr isochron age of cherts from the Yangla deposit being identical with that of host strata. Hence, we conclude that the cherts in the Yangla deposit are of hot-water sedimentary origin, which have a close relationship with the massive sulfide ores. The discovery of hydrothermal cherts from the Yangla copper deposit provides further evidence for the hydrothermal exhalative origin of the massive sulfide deposits.
基金supported by the National Key Research Program of China(Nos.2016YFD0200107and 2016YFD0300802)the National Natural Science Foundation of China(No.41271311)+1 种基金the Earmarked Fund for China Agriculture Research System(No.CARS-03)the Science and Technology Service Network Initiative of Chinese Academy of Sciences(Nos.KFJ-SW-STS-142-03 and KFJ-EW-STS-083-2)
文摘Investigating the effects of residue chemical composition on soil labile organic carbon （LOC） will improve our understanding of soil carbon sequestration. The effects of maize residue chemical composition and soil water content on soil LOC fractions and microbial properties were investigated in a laboratory incubation experiment. Maize shoot and root residues were incorporated into soil at 40% and 70% field capacity. The soils were incubated at 20 ℃ for 150 d and destructive sampling was conducted after 15, 75, and 150 d. Respiration, dissolved organic carbon （DOC）, hot-water extractable organic carbon （HEOC）, and microbial biomass carbon （MBC） were recorded, along with cellulase and β-glucosidase activities and community-level physiological profiles. The results showed that the cumulative respiration was lower in root-amended soils than in shoot-amended soils, indicating that root amendment may be beneficial to C retention in soil. No significant differences in the contents of DOG, HEOC and MBC, enzyme activities, and microbial functional diversity were observed between shoot- and root-amended soils. The high soil water content treatment significantly increased the cumulative respiration, DOC and HEOC contents, and enzyme activities compared to the low soil water content treatment. However, the soil water content treatments had little influence on the MBC content and microbial functional diversity. There were significantly positive correlations between LOC fractions and soil microbial properties. These results indicated that the chemical composition of maize residues had little influence on the DOC, HEOC, and MBC contents, enzyme activities, and microbial functional diversity, while soil water content could significantly influence DOC and HEOC contents and enzyme activities.
基金financially supported by the Strategic Technology Project of Chinese Academy of Sciences,China(XDA05060300)the Science and Technology Research and Development Program of Shaanxi Province,China(2011KJXX63)the Fundamental Research Funds for the Central Universities,China(ZD2013021)
文摘The study was conducted in Zhifanggou Watershed,Shaanxi Province,China,to evaluate the effect of different vegetation types on hot-water extractable C,N and P fractions,with the aim to determine whether hot-water extractable fractions could be used as indicators of soil quality change in Loess Plateau.The six vegetation types established in 1975 were（i） Robinia pseudoacacia L.,（ii） Caragana korshinkii Kom.,（iii） Pinus tabulaeformis Carr.,（iv） P.tabulaeformis-Amorpha fruticosa L.,（v） R.pseudoacacia-A.fruticosa,and（vi） grassland.A cropped hillslope plot and a Platycladus orientalis L.native forest plot were used as references.The results indicated that the conversion of native forest to cropland resulted in a significant decline in the hot-water extractable C,N and P fractions.Hot-water extractable C,N,and P increased when cultivated land was revegetated,but after 30 years the amount of hot-water extractable C,N,and P in revegetated fields was still much lower compared to native forest.Hot-water extractable fractions increased more under mixed-forest than under pure-forest stands.Furthermore,there was a significant correlation between the hot-water extractable fractions and soil chemical and microbiological properties.The results showed that hot-water extractable fractions could be used as indicators of soil quality change on the Loess Plateau.
文摘Although the importance to global oceanography of ice shelf-oceaaa interactions has been recognized for many years, only more recently has its role in the control of ice flow- from the interior, grounded ice sheet into the ocean been more clearly understood. The consequences for global sea level of increasing ice loss from the Antarctic and Greenland ice sheets has prompted rapidly growing research efforts in this area. Here we describe the different techniques commonly employed in the field study of ice shelf-ocean interactions. We focus on techniques used by the British Antarctic Survey, primarily on Filchner-Ronne Ice Shelf, and describe some recent results from instruments deployed both beneath the ice shelf and on its upper surface, which demonstrate variability at a broad range of time scales.
基金supported by the Grant K17281 from Korea Institute of Oriental Medicine(KIOM),provided by the Ministry of Science,ICT and Future Planning(MISP),Republic of Korea
文摘Objective: To investigate the fungistatic activity and synergistic effects of natural products and their constituents, including traditional oriental medicines(TOMs).Methods: Fungistatic activities of TOMs prepared by hot-water(115 ℃) or ethanol(70%; 40 ℃) extraction were determined by their minimum inhibitory concentration.To assess possible synergistic effects, minimum inhibitory concentrations of various combinations were evaluated.Results: By evaluating antifungal susceptibility of Trichophyton rubrum, which is a major causative fungus for several types of dermatophytosis, we confirmed that ethanol extracts were more active than hot-water extracts in 25 of the 36 TOMs, suggesting that the constituents with high hydrophobicity tend to contribute significantly to fungistatic activity.We selected four TOMs with high fungistatic activity, including Aucklandiae radix, Gentianae macrophyllae radix, Scutellariae radix, and Galla rhois, and their synergistic effects were investigated through the combination studies between TOMs or TOM-conventional drug terbinafine.In combinations between four TOMs, partial synergistic effects were observed in Aucklandiae radix–Galla rhois and Gentianae macrophyllae radix–Galla rhois combinations, as supported by the lowest fractional inhibitory concentration index value of 0.66 for both combinations.Furthermore, Galla rhois showed the strongest synergistic effect on growth inhibition of Trichophyton rubrumwith a fractional inhibitory concentration index value of 0.50 in combination with terbinafine.Conclusions: Our findings indicate that the combination of TOMs and TOM-terbinafine may be effective on treatment for chronic and recurrent dermatophytosis by improving fungistatic activity and led to decrease systemic toxicity in clinical practice.
文摘In this study, effects of hot water extract of Paecilomyces hepiali mycelia on hypertension parameters in spontaneously hypertensive rats (SHR) were investigated. The tested parameters included blood pressure, blood and urine biochemical composition, renin and angiotensin II levels in the blood. Prior to these tests, the extract was examined for toxicity. The fungus was cultivated in a solid medium composed of 40 g brown rice, 0.32 g glucose, 0.65 g sucrose, 2 g peptone and 65 ml corn steep liquor. No abnormality or harmful effects were observed in the toxicity test. Administration of a continuous-dose, once daily, to SHR for 27 weeks (from 13 weeks of age) decreased the systolic blood pressure (SBP) significantly. Levels of blood urea nitrogen, β-lipoprotein lipid peroxides and low density lipoprotein were significantly lower in the treated groups when compared to the control group. Urinary protein was significantly reduced in the middle and high dose groups. In comparison with the control group (0 mg/kg/10ml/day), significantly higher values were obtained for total cholesterol in groups that were given middle (170 mg/kg/10ml/day) and high (250 mg/kg/10ml/day) dosages. In all dosages (low, middle and high) the values for triglyceride were significantly higher than value found in the control group. In terms of angiotensin II levels, the value in the control group was markedly higher than values in the other groups. The results suggest that oral administration of hot water extract of P. hepiali mycelia has ability to control hypertension in rats.
基金Supported by FOMIX-BC No.682210 to Center for Scientific Research and Higher Education of Ensenada(CICESE).
文摘Objective:To examine the immune responses of Litopenaeus vannamei after different treatments with a hot water extract of Macrocystis pyrifera(M.pyrifera)and a subsequent challenge with Vibrio campbellii(V.campbellii).Methods:A total of 184 adult white shrimp that were infected with V.campbellii(1×10^(6) CFU/shrimp)were immunostimulate by the hot-water extract from M.pyrifera via either injection(10μg)or immersion(350 mg/L),the experimental controls were injected with either saline solution or V.campbellii(1×10^(6) CFU/shrimp).The bacterial DNA depuration rate,antimicrobial activity and total hemocyte count were evaluated in hemolymph samples at 2,6,12,24,48 and 72 h post-infection.Results:Injected shrimp(10μg M.pyrifera extract)demonstrated the best clearance of bacterial infection,with 82%survival at 72 h post-infection(cellular response).Hemolymph from the immersed organisms had the best antimicrobial activity against Escherichia coli growth;specifically,the most efficient antimicrobial activity was observed at 24 h post-infection.Both types of immunostimulated shrimp had similar total hemocyte counts at 24 h post-infection(1.63-1.59 million/mL);however,after 72 h,injected shrimp had higher total hemocyte counts than immersed animals(2.59 v.s.0.56 million/mL).Conclusions:The injection of the M.pyrifera hot-water extract facilitated a more efficient response to V.campbellii infection due to the stimulation of the hemocytes of the shrimp.In other words,the cellular immune response was more efficient to eliminate bacterial infection than the humoral response in shrimp.
文摘Combined cooling,heating and power(CCHP)systems are characterized by a substantially higher energy-utilization efficiency compared to standalone systems.In this study,an integrated system comprising a solid-oxide fuel cell(SOFC),hot-water storage tank(HWST)and absorption refrigeration(AR)cycle is considered.The SOFC model was developed in Aspen Plus®.It was used to determine the thermodynamic properties of the exhaust gas that was then used to provide heat for the HWST and to drive the AR cycle.Thermodynamic models for the AR cycles were developed in Engineering Equation Solver,considering LiBr-H2O and NH3-H2O as working fluids.The sensitivity analysis of a number of SOFC output parameters has been carried out.The most optimal case was characterized with the coefficient of performance(COP)and CCHP efficiency of 0.806 and 85.2%for the LiBr-H2O system,and 0.649 and 83.6%for the NH3-H2O system,respectively.Under such optimal operating conditions,the SOFC was characterized by the net electrical efficiency of 57.5%and the net power output of 123.66 kW.Data from the optimal solution were used to perform the thermodynamic study and sensitivity analysis to assess the influence of different absorption cycle operating conditions and to identify possible applications for the considered integrated systems.
