In order to evaluate the pharmacokinetic profile of paliperidone extended-release tablets in vivo,a simple and rapid ultra-high performance liquid chromatographyetandem mass spectrometry(UHPLCeMS/MS)method was develop...In order to evaluate the pharmacokinetic profile of paliperidone extended-release tablets in vivo,a simple and rapid ultra-high performance liquid chromatographyetandem mass spectrometry(UHPLCeMS/MS)method was developed and validated for the determination of paliperidone in beagle dog plasma.Paliperidone and diazepam(internal standard)were extracted from plasma samples with diethyl ether,and then separated on a C_(18) column(2.1×50 mm,2.6 mm)under gradient elution with methanol-0.1%formic acid at a flow rate of 0.3 ml/min.The compounds were detected using a triple-quadrupole mass spectrometer equipped with an electrospray ionization(ESI)source.The validated method was linear over the concentration range of 1.00-1000.00 ng/ml and the lower limit of quantitation was 1.00 ng/ml.The intra-day and inter-day precision values were not more than 15%(relative standard deviation<20%at low levels),while the accuracy was within±10%of nominal values.The validated UHPLC-MS/MS method was successfully applied to an oral pharmacokinetic study of paliperidone extended-release tablets in a beagle dog.展开更多
The microstructures, friction and wear behavior under dry sliding condition of electrodeposited amorphous Fe-Co-W alloy deposits heat treated at different temperatures were studied. A comparative study of hard chrome ...The microstructures, friction and wear behavior under dry sliding condition of electrodeposited amorphous Fe-Co-W alloy deposits heat treated at different temperatures were studied. A comparative study of hard chrome deposit under the same testing condition was also made. The experimental results show that the hardness and wear resistance of amorphous Fe-Co-W alloy deposits are improved with the increasing of heat treatment temperature, and reach the maximum value at 800 ℃, then decrease above 800 ℃. Under 40 N load, the wear resistance properties of the alloy deposits heat treated at 800 ℃ are superior to those of hard chrome deposit. The main wear mechanisms of amorphous Fe-Co-W alloy deposits heat treated below 600 ℃ are peeling, plastic and flowing deformation; when the deposits are heat treated above 700 ℃, they are plastic and flowing deformation. While the main wear mechanisms of hard chrome are abrasive wear, fatigue and peeling.展开更多
The spatial prediction of geothermal sites along the southeast side of Taihang Mountain in the Tangyin rift is a critical goal in the development of renewable energy resources in cities such as Hebi in Henan province,...The spatial prediction of geothermal sites along the southeast side of Taihang Mountain in the Tangyin rift is a critical goal in the development of renewable energy resources in cities such as Hebi in Henan province,which has significant potential for geothermal energy production due to the existence of deep faults and Cenozoic volcano.The study aimed to delineate areas with high geothermal manifestations for detailed geothermal exploration and well-test drilling.To define favorable zones for geothermal potentiality,multi-source datasets were chosen to generate evidence thematic layers that demonstrate the distribution of geothermal anomalies such as geologic maps,structural maps,Land Surface Temperature maps(LST),and hydrothermal mineral alterations maps.The remote sensing and Geographical Information System(GIS)approaches were integrated to map fossil geothermal manifestations and appraise the promising geothermal zones from Landsat 8 OLI/TIRS and Advanced Spaceborne Thermal Emission and Reflection Radiometer-Digital Elevation Model(ASTER-DEM)dataset using the Analytic Hierarchy Process(AHP),which is one of the Mult-criteria Decision Making methods.Results show LST values ranging from 22.6℃ to 45.4℃,with the highest values found along the faults and volcanic areas.The hydrothermal alteration minerals discriminated from band ratios of 4/2,6/5,and 6/7 for iron oxide,ferrous minerals,and clays reveal the presence of high amount of montmorillonite and illite minerals along the faults and volcanoes which are related to hot fluid circulation from subsurface.Structural analysis shows that the major structural trend follows the NNE Tangdong and Tangxi faults,with high density on the west side of the Tangxi fault where there is good exposure of outcrop but less fault density on the east side due to sedimentation in a low land which may conceal geological structures.Lastly,all the thematic layers of geothermal factors were reclassified,ranked,and integrated by the weight overlay logic model based on the influence of geothermal suitability to map potential areas for geothermal resources whereby 5 zones were obtained ranging from very poor to very good.The promising potential sites are mostly found along the highly deep structures of the major Tangxi fault crosscutting the permeable lithology of carbonate rocks and around the Hebi volcanoes.The distribution of hot springs and geothermal wells of the Hebi field were correlated and verified against the potential geothermal anomalies map.The overall integrated method proposes an advanced technique for designing the Tangyin rift’s exploration plan and development actions for geothermal resources utilization,which can be used for exploration of any unveiling geothermal potential sites.展开更多
In view of the planning practices of Hexi Village,Chini Town,Huadu District,Guangzhou City,general situation of the village was introduced,"ecological, convenient,high-efficiency,sharable"were taken as princ...In view of the planning practices of Hexi Village,Chini Town,Huadu District,Guangzhou City,general situation of the village was introduced,"ecological, convenient,high-efficiency,sharable"were taken as principles for the village planning.The village planning was elaborated from 4 perspectives:coordination between town planning and village planning,comprehensive village planning,renovation of old village,construction planning of new village.The implementation projects were summarized to discuss village planning.And it was proposed that the village planning should use construction land intensively and demonstrate regional characteristics.展开更多
The research investigated the corrosion of the reinjection water system to ensure the safe production of the system.By analyzing the composition of the methanol-containing wastewater,the corrosion status of the inject...The research investigated the corrosion of the reinjection water system to ensure the safe production of the system.By analyzing the composition of the methanol-containing wastewater,the corrosion status of the injection water system was studied by the on-site materials 20#steel,Q235B steel and L316 steel for that the methanol-containing wastewater of a natural gas processing plant in northern Shaanxi had high acidity,Cl-and sulfide contents,salinity and corrosion.Then the grey system theory modeling software 3.0 was used to study the influence degree of various corrosion factors on the corrosion rate and depth of Q235B steel.The most important factors were determined,and countermeasures against corrosion were proposed.The results showed that L316 steel was more resistant to corrosion,and the corrosion rate was 0.0015 mm/a,which was less than the national standard(0.0760 mm/a).The maximum corrosion depth was 47.63μm,which was the lowest among the three materials.The corrosion rate and depth were the parent factors.Among the four factors of sulfide,Cl-,salinity and pH,grey relational degrees of sulfide were 0.75 and 0.80,respectively,which was the most important factor causing corrosion;using sulfur corrosion inhibitor protection method,TS-792C was selected by electrochemical method from three corrosion inhibitors.The impedance data simulation software ZSimpWin was used to simulate the equivalent circuit diagram,and the impedance of Q235B steel was the largest.The corrosion inhibition rate was up to 90.26%when corrosion rate was 0.0130 mm/a under the fitting of Tafel polarization curve,with the best anti-sulfur effect.At 80℃and a sulfide content of 300 mg/L,the corrosion rate of Q235B steel was less than 0.0760 mm/a.When the added amount was 100 mg/L,the corrosion current density and corrosion rate of the reinjection sewage was 0.462 mA/cm 2 and 0.0505 mm/a,both at the lowest values and with good temperature and sulfur resistance.展开更多
Total reflection x-ray fluorescence analysis is applied to trace element detection in liquid for effective environmental monitoring.This analytical approach requires x-ray total reflection mirrors.In order to achieve ...Total reflection x-ray fluorescence analysis is applied to trace element detection in liquid for effective environmental monitoring.This analytical approach requires x-ray total reflection mirrors.In order to achieve high sensitivity element detection,the mirrors require high surface quality for high x-ray reflectivity.Surface finishing for x-ray mirrors is typically conducted through a series of abrasive processes,such as grinding and polishing,and is thus time consuming.The purpose of this study is to streamline and enhance the surface finishing process based on unique high quality grinding techniques for the production of x-ray total reflection mirrors.展开更多
Manganese superoxide dismutase(MnSOD)is an antioxidant that exists in mitochondria and can effectively remove superoxide anions in mitochondria.In a dark,high-pressure,and low-temperature deep-sea environment,MnSOD is...Manganese superoxide dismutase(MnSOD)is an antioxidant that exists in mitochondria and can effectively remove superoxide anions in mitochondria.In a dark,high-pressure,and low-temperature deep-sea environment,MnSOD is essential for the survival of sea cucumbers.Six MnSODs were identified from the transcriptomes of deep and shallow-sea sea cucumbers.To explore their environmental adaptation mechanism,we conducted environmental selection pressure analysis through the branching site model of PAML software.We obtained night positive selection sites,and two of them were significant(97F→H,134K→V):97F→H located in a highly conservative characteristic sequence,and its polarity c hange might have a great impact on the function of MnSOD;134K→V had a change in piezophilic a bility,which might help MnSOD adapt to the environment of high hydrostatic pressure in the deepsea.To further study the effect of these two positive selection sites on MnSOD,we predicted the point mutations of F97H and K134V on shallow-sea sea cucumber by using MAESTROweb and PyMOL.Results show that 97F→H,134K→V might improve MnSOD’s efficiency of scavenging superoxide a nion and its ability to resist high hydrostatic pressure by moderately reducing its stability.The above results indicated that MnSODs of deep-sea sea cucumber adapted to deep-sea environments through their amino acid changes in polarity,piezophilic behavior,and local stability.This study revealed the correlation between MnSOD and extreme environment,and will help improve our understanding of the organism’s adaptation mechanisms in deep sea.展开更多
Although the solid-state lighting market is growing rapidly, it is still difficult to obtain ultra-high brightness white light emitting diodes(LEDs). V-pits are inevitably introduced during the metalorganic chemical v...Although the solid-state lighting market is growing rapidly, it is still difficult to obtain ultra-high brightness white light emitting diodes(LEDs). V-pits are inevitably introduced during the metalorganic chemical vapor deposition(MOCVD)growth of multiple quantum wells(MQWs) in Ⅲ–nitride LEDs, and thus affecting the carrier dynamics of the LEDs.Specifically designed structures are fabricated to study the influence of the V-pits on the hole transportation and efficiency droop, and double quantum wells(QWs) are used to monitor the transportation and distribution of holes based on their emission intensity. It is found that when compared with the planar QWs, the injection of holes into the QWs through the side walls of the V-pits changes the distribution of holes among the MQWs. This results in a higher probability of hole injection into the middle QWs and enhanced emission therein, and, consequently, a lower efficiency droop.展开更多
With the rapid development of the current economy,the demand for mineral resources is increasing.While further promoting the development of the mining industry,it has also caused great damage to the mining environment...With the rapid development of the current economy,the demand for mineral resources is increasing.While further promoting the development of the mining industry,it has also caused great damage to the mining environment and seriously threatening social security.Mine environmental protection and governance has become an important measure that cannot be delayed.This paper analyzes the problems existing in the current mine environment,and further puts forward relevant suggestions on mine environmental protection and management for your reference.展开更多
In this paper, we conduct research on the novel English education mode based on feedback learning and interactive teaching method. Business English, which is based on general English, from the angle of English languag...In this paper, we conduct research on the novel English education mode based on feedback learning and interactive teaching method. Business English, which is based on general English, from the angle of English language features of text represents connotation of business English vocabulary expressed more, word ambiguity phenomenon is relatively common, meaning and pragmatic choice depends on the context. Our research starts from the analysis of the novel education pattern with the feedback learning and interactive teaching integration. Our education mode will let the students and the teachers interact with others and encourage the better participation passion that is meaningful.展开更多
As a result of several decades of peat extraction, the area of cutaway peatlands in Finland totals ca. 50,000 ha. Furthermore, some 2000 - 3000 ha of peatlands are abandoned annually from active peat extraction. Fores...As a result of several decades of peat extraction, the area of cutaway peatlands in Finland totals ca. 50,000 ha. Furthermore, some 2000 - 3000 ha of peatlands are abandoned annually from active peat extraction. Forestry is considered to be their main after-use option. However, since cutaway peat is generally rich in nitrogen, but poor in phosphorus and potassium, soil amelioration measures are needed for successful vegetation and afforestation. Soil preparations bringing mineral soil into peat surface or recycling of ash containing P and K are alternative ways for soil amelioration. We studied the initial effects of soil preparation and ash fertilization on soil CO<sub>2</sub>-effluxes and colonisation of cutaway peat by vegetation. Oppositely to the previous studies, this study shows that carbon released from the residual peat may be so high that the ash-fertilized cutaway peatlands still act as sources of carbon even after afforestation. However, even though the CO<sub>2</sub>-effluxes following ash fertilization or soil preparation may occasionally exceed the carbon sequestration into growing tree stands, afforestation mostly compensates the CO<sub>2</sub>-effluxes if also we take into consideration the below-ground biomass. In conclusion, our study shows that although ash fertilization enhances the CO<sub>2</sub>-effluxes into the atmosphere, it has beneficial effects on the environment by enabling rapid colonisation of vegetation on these sites which would remain vegetationless for decades without soil amelioration.展开更多
This paper proposes an ontology-driven discovering model for the geographical information services to improve their recall ratio and precision ratio. This model uses the geographical information service ontology. In t...This paper proposes an ontology-driven discovering model for the geographical information services to improve their recall ratio and precision ratio. This model uses the geographical information service ontology. In this paper, first we study the multilevel matching arithmetic of geographical information services. This arithmetic is used for filtering and matching the services in the service register center according to the similarity between services selected and services requested from the definition of the function similarity and credit standing similarity. The matching arithmetic, geographical information service ontology and semantic description constitute the discovering model. Finally, we test and analyze the model from the recall ratio, precision ratio, responsivity and load balance. The result indicates that the ontology-driven discovering model is excellent in recall ratio and precision ratio, and can maintain the dynamic load balance of service copy.展开更多
Cissus rotundifolia Lam.is an evergreen climber that mainly distributed in the tropical savannas of eastern Africa with excellent drought resistance.While the mechanism underlying drought stress response in C.rotundif...Cissus rotundifolia Lam.is an evergreen climber that mainly distributed in the tropical savannas of eastern Africa with excellent drought resistance.While the mechanism underlying drought stress response in C.rotundifolia remains unknown.In this study,we investigated the transcriptomics and flavonoid metabolomics responses of C.rotundifolia leaves under different drought conditions.We identified a total of 2401 differentially expressed genes(DEGs)in drought-treated leaves.The continuously increasing DEGs were significantly enriched in pathways related to phenylpropanoid biosynthesis,flavonoid biosynthesis,and galactose metabolism.The total flavonoids content were also found increased significantly during drought treatment in the leaves of C.rotundifolia.A total of 57 distinct flavonoids were identified using UPLC-MS/MS.Among them,nine out of ten differentially accumulated metabolites(DAMs)displayed notable accumulation profiles under drought conditions.These DAMs included two flavanols[(-)-Catechin gallate and(-)-gallocatechin gallate],two flavonols(myricetin and astragalin),four flavones(orientin,cynaroside,isoorientin,and vitexin),and one flavanone(naringenin-7-glucoside),indicating their pivotal roles in drought response.Additionally,a DEG with continuously high-expression,annotated flavone synthase(FLS)synthesises,and synthetizing myricetin under drought stress was tightly related to additional genes belonging to ABA-signaling genes,stomata movement genes,transcription factors,and protein kinases,these genes were contained Top 10 hub-genes of network constructed all DEGs.The results reflect the significance of FLS and potentially regulatory genes under drought conditions.These findings suggest that flavonoids play a pivotal role in the drought stress response of C.rotundifolia,advancing our understanding of flavonoids accumulation and the transcriptional regulation involved in this process.展开更多
Objective: Atherosclerosis is an inflamrnatory process that results in complex lesions or plaques that protrude into the arterial lumen. Carotid atherosclerotic plaque rupture, with distal atheromatous debris emboliz...Objective: Atherosclerosis is an inflamrnatory process that results in complex lesions or plaques that protrude into the arterial lumen. Carotid atherosclerotic plaque rupture, with distal atheromatous debris embolization, causes cerebrovascular events. This review aimed to explore research progress on the risk factors and outcomes of human carotid atherosclerotic plaques, and the molecular and cellular mechanisms of human carotid atherosclerotic plaque vulnerability for therapeutic intervention. Data Sources: We searched the PubMed database for recently published research articles up to June 2016, with the key words of"risk factors", "outcomes", "'blood components", "molecular mechanisms", "cellular mechanisms", and "human carotid atherosclerotic plaques". Study Selection: The articles, regarding the latest developments related to the risk factors and outcomes, atherosclerotic plaque composition, blood components, and consequences of human carotid atherosclerotic plaques, and the molecular and cellular mechanisms of human carotid atherosclerotic plaque vulnerability for therapeutic intervention, were selected. Results: This review described the latest researches regarding the interactive effects of both traditional and novel risk factors for human carotid atherosclerotic plaques, novel insights into human carotid atherosclerotic plaque composition and blood components, and consequences of human carotid atherosclerotic plaque. Conclusion: Carotid plaque biology and serologic biomarkers of vulnerability can be used to predict the risk ofcerebrovascular events. Furthermore, plaque composition, rather than lesion burden, seems to most predict rupture and subsequent thrombosis.展开更多
This study aimed to pro-environmentally analyze farmers'concerns and behaviors towards soil conservation.This research was a descriptive,causal,and correlational and conducted through a survey technique.The study ...This study aimed to pro-environmentally analyze farmers'concerns and behaviors towards soil conservation.This research was a descriptive,causal,and correlational and conducted through a survey technique.The study population consisted of all farmers at the central district of Sari county,Iran(N=9621).Based on the Cochran's formula,120 farmers were selected using stratified random sampling.The instrument employed in this study was a questionnaire with its validity being confirmed by a number of academic experts and agriculture specialists and its reliability being proved using Cronbach's alpha coefficients in a pilot study(outside the scope of the current study).(0.66≤α≤0.90).The results of the analysis regarding the effects of independent variables on the variables"soil conservation behavior"and"soil conservation concern"indicated that,among the variables affecting these two variables,the variable"attitude towards soil conservation"was the most powerful predictor of"soil conservation concerns"and the variable"social pressures on soil conservation"predicted farmers'"soil conservation behaviors"better.Furthermore,the independent variables used in this research could predict 42% of the variance in terms of soil conservation concern and 21% of the variance in terms of soil conservation behavior.These findings can be practical and appropriate for executive officials since,instead of making efforts to direct change the behavior,they can first focus on conceptual changes and persuasive changes like changing attitudes towards soil conservation.展开更多
Green building development in China relies mainly on compulsory measures that lack incentive policies to motivate the enthusiasm of real estate developers.A floor area ratio bonus is encouraged by the Chinese State Co...Green building development in China relies mainly on compulsory measures that lack incentive policies to motivate the enthusiasm of real estate developers.A floor area ratio bonus is encouraged by the Chinese State Council.In order to ensure the feasibility of a reward quota,residential buildings that met the requirement for energy efficiency during the official assessment in Ningbo in 2014 were selected as research objects.The amount of energy and water savings in terms of the Assessment Standard for Green Building is converted into carbon emissions.Carbon emissions of different star-rated green buildings are then measured in accordance with the actual water and power consumption of residential dwellings in 2014.A regression equation is set up concerning the floor area ratio and index for residential land per capita.A carbon emission-based method is proposed for measuring the reward quota associated with floor area ratio and recommendations are given for development using green building.展开更多
In this paper, transparent poly(vinyl alcohol)/poly(vinyl pyrrolidone)(PVA/PVP) hydrogels were prepared by using the solvent of dimethyl sulfoxide(DMSO) aqueous solution and the method of freeze/thawing. The effect of...In this paper, transparent poly(vinyl alcohol)/poly(vinyl pyrrolidone)(PVA/PVP) hydrogels were prepared by using the solvent of dimethyl sulfoxide(DMSO) aqueous solution and the method of freeze/thawing. The effect of PVP interaction, mechanical property and transparence of PVA/PVP hydrogel was investigated and evaluated by FT-IR analysis, mechanical test machine and UV spectrophotometer. The results showed that when the content of PVP was 8% in the DMSO aqueous solution, the highest transparence of PVA/PVP hydrogel was obtained, with excellent tensile strength values higher than 3.5 MPa. Therefore, the PVA/PVP hydrogel composite has a potential to be used as the transparent core of a novel artificial cornea.展开更多
文摘In order to evaluate the pharmacokinetic profile of paliperidone extended-release tablets in vivo,a simple and rapid ultra-high performance liquid chromatographyetandem mass spectrometry(UHPLCeMS/MS)method was developed and validated for the determination of paliperidone in beagle dog plasma.Paliperidone and diazepam(internal standard)were extracted from plasma samples with diethyl ether,and then separated on a C_(18) column(2.1×50 mm,2.6 mm)under gradient elution with methanol-0.1%formic acid at a flow rate of 0.3 ml/min.The compounds were detected using a triple-quadrupole mass spectrometer equipped with an electrospray ionization(ESI)source.The validated method was linear over the concentration range of 1.00-1000.00 ng/ml and the lower limit of quantitation was 1.00 ng/ml.The intra-day and inter-day precision values were not more than 15%(relative standard deviation<20%at low levels),while the accuracy was within±10%of nominal values.The validated UHPLC-MS/MS method was successfully applied to an oral pharmacokinetic study of paliperidone extended-release tablets in a beagle dog.
文摘The microstructures, friction and wear behavior under dry sliding condition of electrodeposited amorphous Fe-Co-W alloy deposits heat treated at different temperatures were studied. A comparative study of hard chrome deposit under the same testing condition was also made. The experimental results show that the hardness and wear resistance of amorphous Fe-Co-W alloy deposits are improved with the increasing of heat treatment temperature, and reach the maximum value at 800 ℃, then decrease above 800 ℃. Under 40 N load, the wear resistance properties of the alloy deposits heat treated at 800 ℃ are superior to those of hard chrome deposit. The main wear mechanisms of amorphous Fe-Co-W alloy deposits heat treated below 600 ℃ are peeling, plastic and flowing deformation; when the deposits are heat treated above 700 ℃, they are plastic and flowing deformation. While the main wear mechanisms of hard chrome are abrasive wear, fatigue and peeling.
基金the National Natural Science Foundation of China-Henan Talent Training Joint Foundation,which funded this study(Grant No.U1504404)。
文摘The spatial prediction of geothermal sites along the southeast side of Taihang Mountain in the Tangyin rift is a critical goal in the development of renewable energy resources in cities such as Hebi in Henan province,which has significant potential for geothermal energy production due to the existence of deep faults and Cenozoic volcano.The study aimed to delineate areas with high geothermal manifestations for detailed geothermal exploration and well-test drilling.To define favorable zones for geothermal potentiality,multi-source datasets were chosen to generate evidence thematic layers that demonstrate the distribution of geothermal anomalies such as geologic maps,structural maps,Land Surface Temperature maps(LST),and hydrothermal mineral alterations maps.The remote sensing and Geographical Information System(GIS)approaches were integrated to map fossil geothermal manifestations and appraise the promising geothermal zones from Landsat 8 OLI/TIRS and Advanced Spaceborne Thermal Emission and Reflection Radiometer-Digital Elevation Model(ASTER-DEM)dataset using the Analytic Hierarchy Process(AHP),which is one of the Mult-criteria Decision Making methods.Results show LST values ranging from 22.6℃ to 45.4℃,with the highest values found along the faults and volcanic areas.The hydrothermal alteration minerals discriminated from band ratios of 4/2,6/5,and 6/7 for iron oxide,ferrous minerals,and clays reveal the presence of high amount of montmorillonite and illite minerals along the faults and volcanoes which are related to hot fluid circulation from subsurface.Structural analysis shows that the major structural trend follows the NNE Tangdong and Tangxi faults,with high density on the west side of the Tangxi fault where there is good exposure of outcrop but less fault density on the east side due to sedimentation in a low land which may conceal geological structures.Lastly,all the thematic layers of geothermal factors were reclassified,ranked,and integrated by the weight overlay logic model based on the influence of geothermal suitability to map potential areas for geothermal resources whereby 5 zones were obtained ranging from very poor to very good.The promising potential sites are mostly found along the highly deep structures of the major Tangxi fault crosscutting the permeable lithology of carbonate rocks and around the Hebi volcanoes.The distribution of hot springs and geothermal wells of the Hebi field were correlated and verified against the potential geothermal anomalies map.The overall integrated method proposes an advanced technique for designing the Tangyin rift’s exploration plan and development actions for geothermal resources utilization,which can be used for exploration of any unveiling geothermal potential sites.
文摘In view of the planning practices of Hexi Village,Chini Town,Huadu District,Guangzhou City,general situation of the village was introduced,"ecological, convenient,high-efficiency,sharable"were taken as principles for the village planning.The village planning was elaborated from 4 perspectives:coordination between town planning and village planning,comprehensive village planning,renovation of old village,construction planning of new village.The implementation projects were summarized to discuss village planning.And it was proposed that the village planning should use construction land intensively and demonstrate regional characteristics.
文摘The research investigated the corrosion of the reinjection water system to ensure the safe production of the system.By analyzing the composition of the methanol-containing wastewater,the corrosion status of the injection water system was studied by the on-site materials 20#steel,Q235B steel and L316 steel for that the methanol-containing wastewater of a natural gas processing plant in northern Shaanxi had high acidity,Cl-and sulfide contents,salinity and corrosion.Then the grey system theory modeling software 3.0 was used to study the influence degree of various corrosion factors on the corrosion rate and depth of Q235B steel.The most important factors were determined,and countermeasures against corrosion were proposed.The results showed that L316 steel was more resistant to corrosion,and the corrosion rate was 0.0015 mm/a,which was less than the national standard(0.0760 mm/a).The maximum corrosion depth was 47.63μm,which was the lowest among the three materials.The corrosion rate and depth were the parent factors.Among the four factors of sulfide,Cl-,salinity and pH,grey relational degrees of sulfide were 0.75 and 0.80,respectively,which was the most important factor causing corrosion;using sulfur corrosion inhibitor protection method,TS-792C was selected by electrochemical method from three corrosion inhibitors.The impedance data simulation software ZSimpWin was used to simulate the equivalent circuit diagram,and the impedance of Q235B steel was the largest.The corrosion inhibition rate was up to 90.26%when corrosion rate was 0.0130 mm/a under the fitting of Tafel polarization curve,with the best anti-sulfur effect.At 80℃and a sulfide content of 300 mg/L,the corrosion rate of Q235B steel was less than 0.0760 mm/a.When the added amount was 100 mg/L,the corrosion current density and corrosion rate of the reinjection sewage was 0.462 mA/cm 2 and 0.0505 mm/a,both at the lowest values and with good temperature and sulfur resistance.
文摘Total reflection x-ray fluorescence analysis is applied to trace element detection in liquid for effective environmental monitoring.This analytical approach requires x-ray total reflection mirrors.In order to achieve high sensitivity element detection,the mirrors require high surface quality for high x-ray reflectivity.Surface finishing for x-ray mirrors is typically conducted through a series of abrasive processes,such as grinding and polishing,and is thus time consuming.The purpose of this study is to streamline and enhance the surface finishing process based on unique high quality grinding techniques for the production of x-ray total reflection mirrors.
基金Supported by the Guangdong Province Basic and Applied Basic Research Fund Project(No.2020A1515110826)the National Natural Science Foundation of China(No.42006115)the Major Scientific and Technological Projects of Hainan Province(No.ZDKJ2021036)。
文摘Manganese superoxide dismutase(MnSOD)is an antioxidant that exists in mitochondria and can effectively remove superoxide anions in mitochondria.In a dark,high-pressure,and low-temperature deep-sea environment,MnSOD is essential for the survival of sea cucumbers.Six MnSODs were identified from the transcriptomes of deep and shallow-sea sea cucumbers.To explore their environmental adaptation mechanism,we conducted environmental selection pressure analysis through the branching site model of PAML software.We obtained night positive selection sites,and two of them were significant(97F→H,134K→V):97F→H located in a highly conservative characteristic sequence,and its polarity c hange might have a great impact on the function of MnSOD;134K→V had a change in piezophilic a bility,which might help MnSOD adapt to the environment of high hydrostatic pressure in the deepsea.To further study the effect of these two positive selection sites on MnSOD,we predicted the point mutations of F97H and K134V on shallow-sea sea cucumber by using MAESTROweb and PyMOL.Results show that 97F→H,134K→V might improve MnSOD’s efficiency of scavenging superoxide a nion and its ability to resist high hydrostatic pressure by moderately reducing its stability.The above results indicated that MnSODs of deep-sea sea cucumber adapted to deep-sea environments through their amino acid changes in polarity,piezophilic behavior,and local stability.This study revealed the correlation between MnSOD and extreme environment,and will help improve our understanding of the organism’s adaptation mechanisms in deep sea.
基金Project supported by the National Key Research and Development Project of China(Grant No.2017YFB0403303)the Key Technologies Research and Development Program of Tianjin,China(Grant Nos.18YFZCGX00760 and 18YFZCGX00400)
文摘Although the solid-state lighting market is growing rapidly, it is still difficult to obtain ultra-high brightness white light emitting diodes(LEDs). V-pits are inevitably introduced during the metalorganic chemical vapor deposition(MOCVD)growth of multiple quantum wells(MQWs) in Ⅲ–nitride LEDs, and thus affecting the carrier dynamics of the LEDs.Specifically designed structures are fabricated to study the influence of the V-pits on the hole transportation and efficiency droop, and double quantum wells(QWs) are used to monitor the transportation and distribution of holes based on their emission intensity. It is found that when compared with the planar QWs, the injection of holes into the QWs through the side walls of the V-pits changes the distribution of holes among the MQWs. This results in a higher probability of hole injection into the middle QWs and enhanced emission therein, and, consequently, a lower efficiency droop.
文摘With the rapid development of the current economy,the demand for mineral resources is increasing.While further promoting the development of the mining industry,it has also caused great damage to the mining environment and seriously threatening social security.Mine environmental protection and governance has become an important measure that cannot be delayed.This paper analyzes the problems existing in the current mine environment,and further puts forward relevant suggestions on mine environmental protection and management for your reference.
文摘In this paper, we conduct research on the novel English education mode based on feedback learning and interactive teaching method. Business English, which is based on general English, from the angle of English language features of text represents connotation of business English vocabulary expressed more, word ambiguity phenomenon is relatively common, meaning and pragmatic choice depends on the context. Our research starts from the analysis of the novel education pattern with the feedback learning and interactive teaching integration. Our education mode will let the students and the teachers interact with others and encourage the better participation passion that is meaningful.
文摘As a result of several decades of peat extraction, the area of cutaway peatlands in Finland totals ca. 50,000 ha. Furthermore, some 2000 - 3000 ha of peatlands are abandoned annually from active peat extraction. Forestry is considered to be their main after-use option. However, since cutaway peat is generally rich in nitrogen, but poor in phosphorus and potassium, soil amelioration measures are needed for successful vegetation and afforestation. Soil preparations bringing mineral soil into peat surface or recycling of ash containing P and K are alternative ways for soil amelioration. We studied the initial effects of soil preparation and ash fertilization on soil CO<sub>2</sub>-effluxes and colonisation of cutaway peat by vegetation. Oppositely to the previous studies, this study shows that carbon released from the residual peat may be so high that the ash-fertilized cutaway peatlands still act as sources of carbon even after afforestation. However, even though the CO<sub>2</sub>-effluxes following ash fertilization or soil preparation may occasionally exceed the carbon sequestration into growing tree stands, afforestation mostly compensates the CO<sub>2</sub>-effluxes if also we take into consideration the below-ground biomass. In conclusion, our study shows that although ash fertilization enhances the CO<sub>2</sub>-effluxes into the atmosphere, it has beneficial effects on the environment by enabling rapid colonisation of vegetation on these sites which would remain vegetationless for decades without soil amelioration.
基金Supported by the Degree Dissertation of Doctor Natural Science Innovation Foundation of Information Engineering University(2007)
文摘This paper proposes an ontology-driven discovering model for the geographical information services to improve their recall ratio and precision ratio. This model uses the geographical information service ontology. In this paper, first we study the multilevel matching arithmetic of geographical information services. This arithmetic is used for filtering and matching the services in the service register center according to the similarity between services selected and services requested from the definition of the function similarity and credit standing similarity. The matching arithmetic, geographical information service ontology and semantic description constitute the discovering model. Finally, we test and analyze the model from the recall ratio, precision ratio, responsivity and load balance. The result indicates that the ontology-driven discovering model is excellent in recall ratio and precision ratio, and can maintain the dynamic load balance of service copy.
基金supported by International cooperation program,Hubei provice(2024EHA068)the National Science Foundation of China(31961143026)Scientific Research Program of Sino-Africa Joint Research Center(SAJC201614,SAJL201607 and SAJC202101).
文摘Cissus rotundifolia Lam.is an evergreen climber that mainly distributed in the tropical savannas of eastern Africa with excellent drought resistance.While the mechanism underlying drought stress response in C.rotundifolia remains unknown.In this study,we investigated the transcriptomics and flavonoid metabolomics responses of C.rotundifolia leaves under different drought conditions.We identified a total of 2401 differentially expressed genes(DEGs)in drought-treated leaves.The continuously increasing DEGs were significantly enriched in pathways related to phenylpropanoid biosynthesis,flavonoid biosynthesis,and galactose metabolism.The total flavonoids content were also found increased significantly during drought treatment in the leaves of C.rotundifolia.A total of 57 distinct flavonoids were identified using UPLC-MS/MS.Among them,nine out of ten differentially accumulated metabolites(DAMs)displayed notable accumulation profiles under drought conditions.These DAMs included two flavanols[(-)-Catechin gallate and(-)-gallocatechin gallate],two flavonols(myricetin and astragalin),four flavones(orientin,cynaroside,isoorientin,and vitexin),and one flavanone(naringenin-7-glucoside),indicating their pivotal roles in drought response.Additionally,a DEG with continuously high-expression,annotated flavone synthase(FLS)synthesises,and synthetizing myricetin under drought stress was tightly related to additional genes belonging to ABA-signaling genes,stomata movement genes,transcription factors,and protein kinases,these genes were contained Top 10 hub-genes of network constructed all DEGs.The results reflect the significance of FLS and potentially regulatory genes under drought conditions.These findings suggest that flavonoids play a pivotal role in the drought stress response of C.rotundifolia,advancing our understanding of flavonoids accumulation and the transcriptional regulation involved in this process.
文摘Objective: Atherosclerosis is an inflamrnatory process that results in complex lesions or plaques that protrude into the arterial lumen. Carotid atherosclerotic plaque rupture, with distal atheromatous debris embolization, causes cerebrovascular events. This review aimed to explore research progress on the risk factors and outcomes of human carotid atherosclerotic plaques, and the molecular and cellular mechanisms of human carotid atherosclerotic plaque vulnerability for therapeutic intervention. Data Sources: We searched the PubMed database for recently published research articles up to June 2016, with the key words of"risk factors", "outcomes", "'blood components", "molecular mechanisms", "cellular mechanisms", and "human carotid atherosclerotic plaques". Study Selection: The articles, regarding the latest developments related to the risk factors and outcomes, atherosclerotic plaque composition, blood components, and consequences of human carotid atherosclerotic plaques, and the molecular and cellular mechanisms of human carotid atherosclerotic plaque vulnerability for therapeutic intervention, were selected. Results: This review described the latest researches regarding the interactive effects of both traditional and novel risk factors for human carotid atherosclerotic plaques, novel insights into human carotid atherosclerotic plaque composition and blood components, and consequences of human carotid atherosclerotic plaque. Conclusion: Carotid plaque biology and serologic biomarkers of vulnerability can be used to predict the risk ofcerebrovascular events. Furthermore, plaque composition, rather than lesion burden, seems to most predict rupture and subsequent thrombosis.
文摘This study aimed to pro-environmentally analyze farmers'concerns and behaviors towards soil conservation.This research was a descriptive,causal,and correlational and conducted through a survey technique.The study population consisted of all farmers at the central district of Sari county,Iran(N=9621).Based on the Cochran's formula,120 farmers were selected using stratified random sampling.The instrument employed in this study was a questionnaire with its validity being confirmed by a number of academic experts and agriculture specialists and its reliability being proved using Cronbach's alpha coefficients in a pilot study(outside the scope of the current study).(0.66≤α≤0.90).The results of the analysis regarding the effects of independent variables on the variables"soil conservation behavior"and"soil conservation concern"indicated that,among the variables affecting these two variables,the variable"attitude towards soil conservation"was the most powerful predictor of"soil conservation concerns"and the variable"social pressures on soil conservation"predicted farmers'"soil conservation behaviors"better.Furthermore,the independent variables used in this research could predict 42% of the variance in terms of soil conservation concern and 21% of the variance in terms of soil conservation behavior.These findings can be practical and appropriate for executive officials since,instead of making efforts to direct change the behavior,they can first focus on conceptual changes and persuasive changes like changing attitudes towards soil conservation.
基金supported by Zhejiang Provincial Construction Research Projects(2015K150)Natural Science Foundation of Ningbo(2015A610302).
文摘Green building development in China relies mainly on compulsory measures that lack incentive policies to motivate the enthusiasm of real estate developers.A floor area ratio bonus is encouraged by the Chinese State Council.In order to ensure the feasibility of a reward quota,residential buildings that met the requirement for energy efficiency during the official assessment in Ningbo in 2014 were selected as research objects.The amount of energy and water savings in terms of the Assessment Standard for Green Building is converted into carbon emissions.Carbon emissions of different star-rated green buildings are then measured in accordance with the actual water and power consumption of residential dwellings in 2014.A regression equation is set up concerning the floor area ratio and index for residential land per capita.A carbon emission-based method is proposed for measuring the reward quota associated with floor area ratio and recommendations are given for development using green building.
基金National Natural Science Foundation of Chinagrant number:11002016,30900306,81171473 and 11032012
文摘In this paper, transparent poly(vinyl alcohol)/poly(vinyl pyrrolidone)(PVA/PVP) hydrogels were prepared by using the solvent of dimethyl sulfoxide(DMSO) aqueous solution and the method of freeze/thawing. The effect of PVP interaction, mechanical property and transparence of PVA/PVP hydrogel was investigated and evaluated by FT-IR analysis, mechanical test machine and UV spectrophotometer. The results showed that when the content of PVP was 8% in the DMSO aqueous solution, the highest transparence of PVA/PVP hydrogel was obtained, with excellent tensile strength values higher than 3.5 MPa. Therefore, the PVA/PVP hydrogel composite has a potential to be used as the transparent core of a novel artificial cornea.