Steeply dipping seam group, which has complex occurrence conditions, belongs to the steeply dipping seam. The research on the strata movement around the coal face not only improves safe production technology in practi...Steeply dipping seam group, which has complex occurrence conditions, belongs to the steeply dipping seam. The research on the strata movement around the coal face not only improves safe production technology in practice, but also develops the mining theory. By using physical simulation experiments, numerical simulation and site test, the deformation, failure and movement of surrounding rock in Iongwall working face were analyzed. According to the analysis, characteristics of the seam group were formed which is different from the single seam. Asymmetry mechanics, sequential changes and imbalance of strata movement along the tendency working face were summarized. Furthermore the features of upper and lower seams were different. The mining of the lower seam induced more complex strata movement along the strike. Multi-section mining disturbed surrounding rocks in larger areas than the single section mining did, which had an impact on and dynamic loading function to the support when mining the lower seam, and produced a great influence on the stability of support-rock system.展开更多
In this study,dynamic selenonium salts were incorporated into a polyurethane(PU)matrix to develop transparent,healable and antibacterial coatings.Through systematic formulation optimization,optically clear materials w...In this study,dynamic selenonium salts were incorporated into a polyurethane(PU)matrix to develop transparent,healable and antibacterial coatings.Through systematic formulation optimization,optically clear materials with excellent room-temperature hardness were obtained.Fine-tuning the selenonium content established a synergy between antibacterial performance and network dynamics,as evidenced by vitrimer-like rheological behavior at elevated temperatures.Consequently,the coatings exhibited outstanding reprocessability while maintaining high transparency and structural stability after prolonged saltwater exposure.These integrated features underscore the potential of the developed cationic PU coatings as robust,multifunctional materials for electronic device protection and marine antifouling,combining long-term transparency,recyclability,and antibacterial durability.展开更多
Marine pollution is a well-recognized phenomenon that has many negative effects on the marine environment.The effects of marine pollution are due to the discharge of hazardous materials,toxins,or other pollutants into...Marine pollution is a well-recognized phenomenon that has many negative effects on the marine environment.The effects of marine pollution are due to the discharge of hazardous materials,toxins,or other pollutants into the marine environment,which includes seas,estuaries,oceans,and other water bodies,and this unwanted input affects the blue economy.The blue economy,which includes industries and research associated with marine and ocean resources,is often affected by marine pollution on multiple levels,such as economic costs,direct resource impacts,health risks,and infrastructure damage.In one report,the pollution-related issues in many countries were estimated at 9 t/inh and clean-up costs between$12 to$160/t.More extensive pollution mitigation projects might take up to 15 years to conclude and cost up to$500/t.To better understand the role of marine pollution and its impact on the blue economy,some key parameters are discussed as follows:the role of biofouling,volatile organic compounds,the impact of metals,anionic pollutants,and antifouling coatings.The review findings also highlight the impact of marine pollution on ecosystems and associated economic activities,which could be reduced through measures such as better international cooperation,waste management,and the development of sustainable practices.Related information on the strategies and policies that could be adopted for sustainable blue economy are stated after each section.展开更多
Scientific evidence sustains PM_(2.5)particles’inhalation may generate harmful impacts on human beings’health;therefore,theirmonitoring in ambient air is of paramount relevance in terms of public health.Due to the l...Scientific evidence sustains PM_(2.5)particles’inhalation may generate harmful impacts on human beings’health;therefore,theirmonitoring in ambient air is of paramount relevance in terms of public health.Due to the limited number of fixed stations within the air qualitymonitoring networks,development ofmethodological frameworks tomodel ambient air PM_(2.5)particles is primordial to providing additional information on PM_(2.5)exposure and its trends.In this sense,this work aims to offer a global easily-applicable tool to estimate ambient air PM_(2.5)as a function of meteorological conditions using a multivariate analysis.Daily PM_(2.5)data measured by 84 fixed monitoring stations and meteorological data from ERA5(ECMWF Reanalysis v5)reanalysis daily based data between 2000 and 2021 across the United Kingdom were attended to develop the suggested approach.Data from January 2017 to December 2020 were employed to build amathematical expression that related the dependent variable(PM_(2.5))to predictor ones(sea-level pressure,planetary boundary layer height,temperature,precipitation,wind direction and speed),while 2021 data tested the model.Evaluation indicators evidenced a good performance of model(maximum values of RMSE,MAE and MAPE:1.80μg/m^(3),3.24μg/m^(3),and 20.63%,respectively),compiling the current legislation’s requirements for modelling ambient air PM_(2.5)concentrations.A retrospective analysis of meteorological features allowed estimating ambient air PM_(2.5)concentrations from 2000 to 2021.The highest PM_(2.5)concentrations relapsed in theMid-and Southlands,while Northlands sustained the lowest concentrations.展开更多
Coal is the most abundant fossil fuel in the world. Because of the growth of coal mining, coal-fired power plants and coal-burning industries, the increase of the emission of particulates(coarse, fine or ultrafine)is ...Coal is the most abundant fossil fuel in the world. Because of the growth of coal mining, coal-fired power plants and coal-burning industries, the increase of the emission of particulates(coarse, fine or ultrafine)is of great concern. There is a relationship between increasing human morbidity and mortality and progressive environmental air pollution caused by these types of particles. Thus, the knowledge of the physico-chemical composition and ambient concentrations of coal-derived nanoparticles will improve pollution control strategy. Given the current importance of this area of research, the advanced characterization of this coal combustion-derived nanoparticles/nanominerals as well as hazardous elements is likely to be one of the hottest research fields in coming days. In this review, we try to compile the existing knowledge on coal-derived nanoparticles/nanominerals and discuss the advanced level of characterization techniques for future research. This review also provides some of aspects of health risks associated with exposure to ambient nanoparticles. In addition, the presence of some of the hazardous elements in coal and coal combustion activities is also reviewed.展开更多
Using pressure swing adsorption （PSA） technology to purify carbon monoxide （CO） discharged from industrial gases is a high-efficiency and economical method. In this article, a four-bed PSA experiment for CO purifi...Using pressure swing adsorption （PSA） technology to purify carbon monoxide （CO） discharged from industrial gases is a high-efficiency and economical method. In this article, a four-bed PSA experiment for CO purification was improved and optimized, in which a set of 120 m^3·h^-1 pilot-scale PSA device was developed to purify CO from industrial tail gases, a set of control systems suitable for industry production was developed, and the influences of the operating parameters on CO purification were investigated. The experimental results indicated that the pilot-scale PSA device could produce qualified product gas and get high CO recovery ratio under optimized conditions. The research may provide reliable fundamental data, for industrial scale utilization of CO, from industrial tail gases, and have strong market competitive power and a broad promoted application prospect.展开更多
Powder compacted and sintered Nb205 pellets were cathodically polarised against graphite anode in calcium chloride melt at 1173 K to study the influence of various factors on the electrochemical reduction of the oxide...Powder compacted and sintered Nb205 pellets were cathodically polarised against graphite anode in calcium chloride melt at 1173 K to study the influence of various factors on the electrochemical reduction of the oxide. The parameters were; duration and temperature of electrolysis, open porosity of pellets, nature of anode, mode of electrolysis and configuration of the oxide cathode. The experiments were also conducted in KC1, KC1-25 tool% CaC12 and NaC1 melts to understand the effect of melt composition on the electroreduction. Different Ca-Nb-O and Nb-O intermediates were found in the pellets electrolysed for different durations of time in CaC12 melt which eventually reduced to Nb. The current efficiency of the process decreased with increasing duration of electrolysis. Decrease in electrolysis temperature from 1 173 to 1073 K led to the decrease in the rate of reduction of the oxide pellets. Pellets with high open porosity reduced faster. Carbon contamination of the melt was relatively less when pyrolytic graphite was used as anode. Of all the melts studied, the reduction was found to be better in calcium chloride melt, that too when alumina crucible was used as container of the melt.展开更多
Analogues of endomorphin and tripeptidcs modified at positions 4 and 3,respectively,with various phenylalanine analogues were synthesized and their affinities for opioid receptors were evaluated.Most of the peptides e...Analogues of endomorphin and tripeptidcs modified at positions 4 and 3,respectively,with various phenylalanine analogues were synthesized and their affinities for opioid receptors were evaluated.Most of the peptides exhibited potentμ-receptor affinity and selectivity,among them,compound 7（Dmt-Pro-Tmp-Tmp-NH_2） exhibited potent affinity for bothμ-andδ-receptors （K_iμ= 0.47 nmol/L,K_iδ= 1.63 nmol/L）.展开更多
Element profiles of some beach rock samples collected from South East Coast of Tamilnadu, India have been determined using single comparator method of INAA. The geo-chemical behavior of the elements in the region is d...Element profiles of some beach rock samples collected from South East Coast of Tamilnadu, India have been determined using single comparator method of INAA. The geo-chemical behavior of the elements in the region is discussed. The irradiations were done at thermal neutron flux of ~ 1011 cm-2·s-1 at 20kW power using Kalpakkam Mini Reactor (KAMINI), IGCAR, Kalpakkam, Tamilnadu, India. Around 19 elements have been determined from 15 samples by high-resolution gamma spectrometry. The accuracy and precision were evaluated by assaying the irradiated Standard Reference Material (SRM 1646a Estuarine sediment) and were found to be in good agreement with certified values.展开更多
As bifunctional oxygen evolution/reduction electrocatalysts,transition-metal-based single-atom-doped nitrogen-carbon(NC)matrices are promising successors of the corresponding noblemetal-based catalysts,offering the ad...As bifunctional oxygen evolution/reduction electrocatalysts,transition-metal-based single-atom-doped nitrogen-carbon(NC)matrices are promising successors of the corresponding noblemetal-based catalysts,offering the advantages of ultrahigh atom utilization effciency and surface active energy.However,the fabrication of such matrices(e.g.,well-dispersed single-atom-doped M-N4/NCs)often requires numerous steps and tedious processes.Herein,ultrasonic plasma engineering allows direct carbonization in a precursor solution containing metal phthalocyanine and aniline.When combining with the dispersion effect of ultrasonic waves,we successfully fabricated uniform single-atom M-N4(M=Fe,Co)carbon catalysts with a production rate as high as 10 mg min-1.The Co-N4/NC presented a bifunctional potential drop ofΔE=0.79 V,outperforming the benchmark Pt/C-Ru/C catalyst(ΔE=0.88 V)at the same catalyst loading.Theoretical calculations revealed that Co-N4 was the major active site with superior O2 adsorption-desorption mechanisms.In a practical Zn-air battery test,the air electrode coated with Co-N4/NC exhibited a specific capacity(762.8 mAh g(-1))and power density(101.62 mW cm^(-2)),exceeding those of Pt/C-Ru/C(700.8 mAh g^(-1) and 89.16 mW cm^(-2),respectively)at the same catalyst loading.Moreover,for Co-N4/NC,the potential difference increased from 1.16 to 1.47 V after 100 charge-discharge cycles.The proposed innovative and scalable strategy was concluded to be well suited for the fabrication of single-atom-doped carbons as promising bifunctional oxygen evolution/reduction electrocatalysts for metal-air batteries.展开更多
Acid mine drainage （AMD） is one of the major problems in high sulfur coal mining areas generating acidic water. The acidic mine water generated contain hazardous elements in varying concentrations. The Northeastern ...Acid mine drainage （AMD） is one of the major problems in high sulfur coal mining areas generating acidic water. The acidic mine water generated contain hazardous elements in varying concentrations. The Northeastern Indian coalfield produces considerable amounts of AMD. The AMD and metal leaching from coal and mine over burden （OB） are the two important naturally occurring processes. In order to know the AMD potential, the aqueous leaching experiment of a few coal and OB samples from the Ledo colliery of the Northeastern coalfield, Mergherita （India）, at different time periods （1, 3, 5, and 8 h） and at different temperatures （25, 45, 65, and 90℃） were performed in the laboratory. The physico- chemical analysis of the aqueous leachates shows the pH, electrical conductivity （EC）, and total dissolved solid （TDS） in the range of 1.62-3.52, 106-2006 μs/cm, and 106-1003 ppm for the raw coal samples respectively. The OB samples produced pH, EC, and TDS in the range of 3.68-6.92, 48.6-480 μs/cm, and 69.5-240 ppm respectively. From the study, it was revealed that the concentrations of major （Si, A1, K, Na, Fe, Ca, Mg）, minor （Mn） and trace/hazardous elements （As, Ba, Cd, Co, Cr, Cu, Hg, Ni, Pb, Se, Zn） considerably change with leaching time as well as with leaching temperature. Out of these elements As, Cd, Hg, Pb, Cr, and Se are of greater environmental importance. Alteration of the physico-chemical structure of the coal and OB samples resulting from leaching was also studied by field emission scanning electron microscope- energy-dispersive X-ray spectroscopy method. The release of the potentially hazardous elements from the raw coal and OB during leaching time periods to the leachates was detected by inductively coupled plasma-atomic emission spectroscopy and ion-chromatographic analyses. The major minerals found in coal and OB are quartz （SiO2）, pyrite （FeS2）, hematite, marcasite, and kaolinite. The association of different functional groups in minerals and their mode of association were studied by Fourier-transform infrared spectroscopy and X-ray diffraction analytical techniques. The present laboratory study will be useful in relating the characteristics of aqueous leaching from coal and mine OB with the natural weathering condition at the coal mine area.展开更多
Two new iridoid glucosides, serratoside A and serratoside B, were isolated from the aerial parts of Clerodendrum serratum var. amplexifolium Moldenke. Their structures were elucidated by spectral and chemical methods.
Burn-up measurement on an irradiated mixed oxide (MOX) test fuel pellet was carried out through measurements on the dissolver solution by HPLC-Thermal Ionization Mass Spectrometric (TIMS) technique. The studies carrie...Burn-up measurement on an irradiated mixed oxide (MOX) test fuel pellet was carried out through measurements on the dissolver solution by HPLC-Thermal Ionization Mass Spectrometric (TIMS) technique. The studies carried out using HPLC as well as TIMS for quantification of burn-up value are described. While in one case, both the separation and determination of elements of interest (U, Pu and Nd) were carried out by HPLC;in another case, TIMS technique was used to quantify them from the HPLC separated fractions.The rapid separation procedures developed in our laboratory earlier were employed to isolate pure fractions of the desired elements. The individual lanthanide fission products (La to Eu) were separated from each other using dynamic ion-exchange chromatographic technique whereas uranium and plutonium were separated from each other using reversed phase chromatographic technique. The pure fractions of U, Pu and Nd obtained after HPLC separation procedure for “spiked” and “unspiked” dissolver solutions were used in TIMS measurements for the first time in our laboratory. In TIMS analysis, isotopic abundances of uranium, plutonium and neodymium fractions obtained from HPLC separation procedure on an “unspiked” fuel sample were measured. For the determination of U, Pu and Nd by isotopic dilution mass spectrometric technique (IDMS), known quantities of tracers enriched in 238U, 240Pu and 142Nd were added to the pre-weighed dissolver solution and subjected to HPLC separation procedures. The isotope ratios viz. 142Nd/(145Nd +146Nd), 238U/233U and 240Pu/239Pu in the pertinent “spiked” fractions were subsequently measured by TIMS. The spikes were pre-standardized in our laboratory employing reverse isotopic dilution technique against the standard solutions available in our laboratory (for 238U, 239Pu and 142Nd, standard solutions of 233U, 239Pu (of higher abundance than in the sample) and 150Nd were employed as spikes). The burn-up values from duplicate spiking experiments were computed based on the summation of 145Nd + 146Nd. The concentrations of neodymium, uranium and plutonium were also measured using HPLC with post-column derivatisation technique using aresenazo(III) as the post-column reagent. The atom % burn-up computed from HPLC and TIMS techniques were in good agreement.展开更多
Objective:To determine the biological effects of essential oils(EOs) isolated from Cymbopogon iiardus,Cymbopogon Jlexuosus and Cvrnbopogon marlinii grown in Colombia against two Lepidoptera larvae,common pests in the ...Objective:To determine the biological effects of essential oils(EOs) isolated from Cymbopogon iiardus,Cymbopogon Jlexuosus and Cvrnbopogon marlinii grown in Colombia against two Lepidoptera larvae,common pests in the oil palm.Methods:Specimens were captured in the field and the antifeedant activity and dermal contact lethality of EOs were measured against Acharia fusca and Euprosterna elaeasa(Lepidoptera:I.imacodidae) at various concentrations 0.002-0.600 μL/cm^3 and 0.002-8 μL/g,respectively.Results:All EOs exhibited strong antifeedant and toxicity activity toward Acharia fusca and Euprosterna elaeasa larvae.Cymbopogon marlinii oil was llie most active againsl both pest insect species,although all tested EOs were better than the synthetic;repellent IR535 on both insects.Conclusions:Colombian EOs have potential for integrated pest management programs in the oil palm industry.展开更多
The solutions of the Schrodinger equation with quantum mechanical gravitational potential plus harmonic oscillator potential have been presented using the parametric Nikiforov-Uvarov method. The bound state energy eig...The solutions of the Schrodinger equation with quantum mechanical gravitational potential plus harmonic oscillator potential have been presented using the parametric Nikiforov-Uvarov method. The bound state energy eigen values and the corresponding un-normalized eigen functions are obtained in terms of Laguerre polynomials. Also a special case of the potential has been considered and its energy eigen values are obtained.展开更多
The deterioration of environmental conditions is the major contributory factor to poor health and quality of life that hinders sustainable development in any region.Coal mining is one of the major industries that cont...The deterioration of environmental conditions is the major contributory factor to poor health and quality of life that hinders sustainable development in any region.Coal mining is one of the major industries that contribute to the economy of a country but it also impacts the environment.The chemical parameters of the coal,overburden,soil and sediments along with the coal mine drainage(CMD)were investigated in order to understand the overall environmental impact from high sulphur coal mining at northeastern coalfield(India).It was found that the total sulphur content of the coal is noticeably high compared to the overburden(OB)and soil.The volatile matter of the coal is sufficiently high against the high ash content of the soil and overburden.The water samples have a High Electrical Conductivity(EC)and high Total Dissolve Solid(TDS).Lower values of pH,indicate the dissolution of minerals present in the coal as well as other minerals in the mine rejects/overburden.The chemical and nano-mineralogical composition of coal,soil and overburden samples was studied using a High Resolution-Transmission Electron Microscopy(HR-TEM),Energy Dispersive Spectroscopy(EDS),Selected-Area Diffraction(SAED),Field Emission-Scanning Electron Microscopy(FE-SEM)/EDS,X-ray diffraction(XRD),Fourier Transform Infrared Spectroscopy(FTIR),Raman and Ion-Chromatographic analysis,and Mossbauer spectroscopy.From different geochemical analysis it has been found that the mine water sample from Ledo colliery has the lowest pH value of 3.30,Tirap colliery samples have the highest electrical conductivity value of5.40 ms cm^(-1)Both Ledo and Tirap coals have total sulphur contents within the range 3-3.50%.The coal mine water from Tirap colliery(TW-15 B)has high values of Mg^(2+)(450 ppm),and Br^-(227.17 ppm).XRD analysis revealed the presence of minerals including quartz and hematite in the coals.Mineral analysis of coal mine overburden(OB)indicates the presence both of pyrite and marcasite which was also confirmed in XRD and Mossbauer spectral analysis.The presented data of the minerals and ultra/nano-particles present shows their ability to control the mobility of hazardous elements,suggesting possible use in environmental management technology,including restoration of the delicate Indian coal mine areas.展开更多
A rational regulation of the solar water splitting reaction pathway by adjusting the surface composition and phase structure of catalysts is a substantial approach to ameliorate the sluggish reaction kinetics and impr...A rational regulation of the solar water splitting reaction pathway by adjusting the surface composition and phase structure of catalysts is a substantial approach to ameliorate the sluggish reaction kinetics and improve the energy conversion efficiency.In this study,we demonstrate a nanocrystalline iron pyrophosphate(Fe_(4)(P_(2)O_(7))_(3),FePy)-regulated hybrid overlayer with amorphous iron phosphate(FePO_(4),FePi)on the surface of metal oxide nanostructure with boosted photoelectrochemical(PEC)water oxidation.By manipulating the facile electrochemical surface treatment followed by the phosphating process,nanocrystalline FePy is localized in the FePi amorphous overlayer to form a heterogeneous hybrid structure.The FePy-regulated hybrid overlayer(FePy@FePi)results in significantly enhanced PEC performance with long-term durability.Compared with the homogeneous FePi amorphous overlayer,FePy@FePi can improve the charge transfer efficiency more significantly,from 60% of FePi to 79%of FePy@FePi.Our density-functional theory calculations reveal that the coexistence of FePi and FePy phases on the surface of metal oxide results in much better oxygen evolution reaction kinetics,where the FePi was found to have a typical down-hill reaction for the conversion from OH*to O_(2),while FePy has a low free energy for the formation of OH*.展开更多
基金the New Century Excellent Talents in University of China(NCET-04-972)
文摘Steeply dipping seam group, which has complex occurrence conditions, belongs to the steeply dipping seam. The research on the strata movement around the coal face not only improves safe production technology in practice, but also develops the mining theory. By using physical simulation experiments, numerical simulation and site test, the deformation, failure and movement of surrounding rock in Iongwall working face were analyzed. According to the analysis, characteristics of the seam group were formed which is different from the single seam. Asymmetry mechanics, sequential changes and imbalance of strata movement along the tendency working face were summarized. Furthermore the features of upper and lower seams were different. The mining of the lower seam induced more complex strata movement along the strike. Multi-section mining disturbed surrounding rocks in larger areas than the single section mining did, which had an impact on and dynamic loading function to the support when mining the lower seam, and produced a great influence on the stability of support-rock system.
基金financially supported by the National Natural Science Foundation of China(Nos.21971177 and 52503155)Natural Science Foundation of the Jiangsu Higher Education Institution of China(No.22KJA150004)+7 种基金China Scholarship Council(No.202206920034)Research Foundation Flanders(FWO)(Application 1S34725N)Priority Academic Program Development(PAPD)of Jiangsu Higher Education InstitutionsJiangsu Key Laboratory of Advanced Functional Polymers Design and ApplicationSoochow UniversitySuzhou Key Laboratory of Macromolecular Design and Precision SynthesisProgram of Innovative Research Team of Soochow Universityfunding from the European Research Council(ERC)under the European Union’s Horizon 2020 Research and Innovation Program 101021081(ERC-AdG-2020,CiMaC-project)。
文摘In this study,dynamic selenonium salts were incorporated into a polyurethane(PU)matrix to develop transparent,healable and antibacterial coatings.Through systematic formulation optimization,optically clear materials with excellent room-temperature hardness were obtained.Fine-tuning the selenonium content established a synergy between antibacterial performance and network dynamics,as evidenced by vitrimer-like rheological behavior at elevated temperatures.Consequently,the coatings exhibited outstanding reprocessability while maintaining high transparency and structural stability after prolonged saltwater exposure.These integrated features underscore the potential of the developed cationic PU coatings as robust,multifunctional materials for electronic device protection and marine antifouling,combining long-term transparency,recyclability,and antibacterial durability.
基金Supported by the President’s International Fellowship Initiative of Chinese Academy of Sciences(No.2024 PVC 0010)。
文摘Marine pollution is a well-recognized phenomenon that has many negative effects on the marine environment.The effects of marine pollution are due to the discharge of hazardous materials,toxins,or other pollutants into the marine environment,which includes seas,estuaries,oceans,and other water bodies,and this unwanted input affects the blue economy.The blue economy,which includes industries and research associated with marine and ocean resources,is often affected by marine pollution on multiple levels,such as economic costs,direct resource impacts,health risks,and infrastructure damage.In one report,the pollution-related issues in many countries were estimated at 9 t/inh and clean-up costs between$12 to$160/t.More extensive pollution mitigation projects might take up to 15 years to conclude and cost up to$500/t.To better understand the role of marine pollution and its impact on the blue economy,some key parameters are discussed as follows:the role of biofouling,volatile organic compounds,the impact of metals,anionic pollutants,and antifouling coatings.The review findings also highlight the impact of marine pollution on ecosystems and associated economic activities,which could be reduced through measures such as better international cooperation,waste management,and the development of sustainable practices.Related information on the strategies and policies that could be adopted for sustainable blue economy are stated after each section.
基金supported by the Collaborative Research Project(CRP)grant,Nazarbayev University(Nos.11022021CRP1512,211123CRP1604)PK acknowledges the support from the NERC-funded projects ASAP-Delhi(NE/P016510/1),GreenCities(NE/P016510/1)RECLAIM Network Plus(EP/W034034/1).
文摘Scientific evidence sustains PM_(2.5)particles’inhalation may generate harmful impacts on human beings’health;therefore,theirmonitoring in ambient air is of paramount relevance in terms of public health.Due to the limited number of fixed stations within the air qualitymonitoring networks,development ofmethodological frameworks tomodel ambient air PM_(2.5)particles is primordial to providing additional information on PM_(2.5)exposure and its trends.In this sense,this work aims to offer a global easily-applicable tool to estimate ambient air PM_(2.5)as a function of meteorological conditions using a multivariate analysis.Daily PM_(2.5)data measured by 84 fixed monitoring stations and meteorological data from ERA5(ECMWF Reanalysis v5)reanalysis daily based data between 2000 and 2021 across the United Kingdom were attended to develop the suggested approach.Data from January 2017 to December 2020 were employed to build amathematical expression that related the dependent variable(PM_(2.5))to predictor ones(sea-level pressure,planetary boundary layer height,temperature,precipitation,wind direction and speed),while 2021 data tested the model.Evaluation indicators evidenced a good performance of model(maximum values of RMSE,MAE and MAPE:1.80μg/m^(3),3.24μg/m^(3),and 20.63%,respectively),compiling the current legislation’s requirements for modelling ambient air PM_(2.5)concentrations.A retrospective analysis of meteorological features allowed estimating ambient air PM_(2.5)concentrations from 2000 to 2021.The highest PM_(2.5)concentrations relapsed in theMid-and Southlands,while Northlands sustained the lowest concentrations.
基金partial financial assistance of Ministry of Environment Forest and Climate Change (MoEFCC), Govt. of India (GPP-0325)
文摘Coal is the most abundant fossil fuel in the world. Because of the growth of coal mining, coal-fired power plants and coal-burning industries, the increase of the emission of particulates(coarse, fine or ultrafine)is of great concern. There is a relationship between increasing human morbidity and mortality and progressive environmental air pollution caused by these types of particles. Thus, the knowledge of the physico-chemical composition and ambient concentrations of coal-derived nanoparticles will improve pollution control strategy. Given the current importance of this area of research, the advanced characterization of this coal combustion-derived nanoparticles/nanominerals as well as hazardous elements is likely to be one of the hottest research fields in coming days. In this review, we try to compile the existing knowledge on coal-derived nanoparticles/nanominerals and discuss the advanced level of characterization techniques for future research. This review also provides some of aspects of health risks associated with exposure to ambient nanoparticles. In addition, the presence of some of the hazardous elements in coal and coal combustion activities is also reviewed.
基金the National Natural Science Foundation of China(50768006)the National High Technology Research andDevelopment Program of China(2004AA649040).
文摘Using pressure swing adsorption （PSA） technology to purify carbon monoxide （CO） discharged from industrial gases is a high-efficiency and economical method. In this article, a four-bed PSA experiment for CO purification was improved and optimized, in which a set of 120 m^3·h^-1 pilot-scale PSA device was developed to purify CO from industrial tail gases, a set of control systems suitable for industry production was developed, and the influences of the operating parameters on CO purification were investigated. The experimental results indicated that the pilot-scale PSA device could produce qualified product gas and get high CO recovery ratio under optimized conditions. The research may provide reliable fundamental data, for industrial scale utilization of CO, from industrial tail gases, and have strong market competitive power and a broad promoted application prospect.
基金financial assistance from IGCAR, Department of Atomic Energy,India
文摘Powder compacted and sintered Nb205 pellets were cathodically polarised against graphite anode in calcium chloride melt at 1173 K to study the influence of various factors on the electrochemical reduction of the oxide. The parameters were; duration and temperature of electrolysis, open porosity of pellets, nature of anode, mode of electrolysis and configuration of the oxide cathode. The experiments were also conducted in KC1, KC1-25 tool% CaC12 and NaC1 melts to understand the effect of melt composition on the electroreduction. Different Ca-Nb-O and Nb-O intermediates were found in the pellets electrolysed for different durations of time in CaC12 melt which eventually reduced to Nb. The current efficiency of the process decreased with increasing duration of electrolysis. Decrease in electrolysis temperature from 1 173 to 1073 K led to the decrease in the rate of reduction of the oxide pellets. Pellets with high open porosity reduced faster. Carbon contamination of the melt was relatively less when pyrolytic graphite was used as anode. Of all the melts studied, the reduction was found to be better in calcium chloride melt, that too when alumina crucible was used as container of the melt.
基金was supported by grants 08KJB350002 and 08NMUZ028in part by the Intramural Research Program of the NIH and NIEHS
文摘Analogues of endomorphin and tripeptidcs modified at positions 4 and 3,respectively,with various phenylalanine analogues were synthesized and their affinities for opioid receptors were evaluated.Most of the peptides exhibited potentμ-receptor affinity and selectivity,among them,compound 7（Dmt-Pro-Tmp-Tmp-NH_2） exhibited potent affinity for bothμ-andδ-receptors （K_iμ= 0.47 nmol/L,K_iδ= 1.63 nmol/L）.
文摘Element profiles of some beach rock samples collected from South East Coast of Tamilnadu, India have been determined using single comparator method of INAA. The geo-chemical behavior of the elements in the region is discussed. The irradiations were done at thermal neutron flux of ~ 1011 cm-2·s-1 at 20kW power using Kalpakkam Mini Reactor (KAMINI), IGCAR, Kalpakkam, Tamilnadu, India. Around 19 elements have been determined from 15 samples by high-resolution gamma spectrometry. The accuracy and precision were evaluated by assaying the irradiated Standard Reference Material (SRM 1646a Estuarine sediment) and were found to be in good agreement with certified values.
基金supported by Global Frontier Program through the Global Frontier Hybrid Interface materials(GFHIM)of the National Research Foundation of Korea(NRF)funded by the ministry of science,ICT and Future Planning(2013M3A6B1078874)co-supported by Busan Innovation Institute of Industry,Science&Technology Planning(BISTEP)+1 种基金the financial support of Federal Ministry of Education and Research(BMBF)under the“Make Our Planet Great Again-German Research Initiative”(MOPGAGRI),57429784implemented by the German Academic Exchange Service Deutscher Akademischer Austauschdienst(DAAD)。
文摘As bifunctional oxygen evolution/reduction electrocatalysts,transition-metal-based single-atom-doped nitrogen-carbon(NC)matrices are promising successors of the corresponding noblemetal-based catalysts,offering the advantages of ultrahigh atom utilization effciency and surface active energy.However,the fabrication of such matrices(e.g.,well-dispersed single-atom-doped M-N4/NCs)often requires numerous steps and tedious processes.Herein,ultrasonic plasma engineering allows direct carbonization in a precursor solution containing metal phthalocyanine and aniline.When combining with the dispersion effect of ultrasonic waves,we successfully fabricated uniform single-atom M-N4(M=Fe,Co)carbon catalysts with a production rate as high as 10 mg min-1.The Co-N4/NC presented a bifunctional potential drop ofΔE=0.79 V,outperforming the benchmark Pt/C-Ru/C catalyst(ΔE=0.88 V)at the same catalyst loading.Theoretical calculations revealed that Co-N4 was the major active site with superior O2 adsorption-desorption mechanisms.In a practical Zn-air battery test,the air electrode coated with Co-N4/NC exhibited a specific capacity(762.8 mAh g(-1))and power density(101.62 mW cm^(-2)),exceeding those of Pt/C-Ru/C(700.8 mAh g^(-1) and 89.16 mW cm^(-2),respectively)at the same catalyst loading.Moreover,for Co-N4/NC,the potential difference increased from 1.16 to 1.47 V after 100 charge-discharge cycles.The proposed innovative and scalable strategy was concluded to be well suited for the fabrication of single-atom-doped carbons as promising bifunctional oxygen evolution/reduction electrocatalysts for metal-air batteries.
文摘Acid mine drainage （AMD） is one of the major problems in high sulfur coal mining areas generating acidic water. The acidic mine water generated contain hazardous elements in varying concentrations. The Northeastern Indian coalfield produces considerable amounts of AMD. The AMD and metal leaching from coal and mine over burden （OB） are the two important naturally occurring processes. In order to know the AMD potential, the aqueous leaching experiment of a few coal and OB samples from the Ledo colliery of the Northeastern coalfield, Mergherita （India）, at different time periods （1, 3, 5, and 8 h） and at different temperatures （25, 45, 65, and 90℃） were performed in the laboratory. The physico- chemical analysis of the aqueous leachates shows the pH, electrical conductivity （EC）, and total dissolved solid （TDS） in the range of 1.62-3.52, 106-2006 μs/cm, and 106-1003 ppm for the raw coal samples respectively. The OB samples produced pH, EC, and TDS in the range of 3.68-6.92, 48.6-480 μs/cm, and 69.5-240 ppm respectively. From the study, it was revealed that the concentrations of major （Si, A1, K, Na, Fe, Ca, Mg）, minor （Mn） and trace/hazardous elements （As, Ba, Cd, Co, Cr, Cu, Hg, Ni, Pb, Se, Zn） considerably change with leaching time as well as with leaching temperature. Out of these elements As, Cd, Hg, Pb, Cr, and Se are of greater environmental importance. Alteration of the physico-chemical structure of the coal and OB samples resulting from leaching was also studied by field emission scanning electron microscope- energy-dispersive X-ray spectroscopy method. The release of the potentially hazardous elements from the raw coal and OB during leaching time periods to the leachates was detected by inductively coupled plasma-atomic emission spectroscopy and ion-chromatographic analyses. The major minerals found in coal and OB are quartz （SiO2）, pyrite （FeS2）, hematite, marcasite, and kaolinite. The association of different functional groups in minerals and their mode of association were studied by Fourier-transform infrared spectroscopy and X-ray diffraction analytical techniques. The present laboratory study will be useful in relating the characteristics of aqueous leaching from coal and mine OB with the natural weathering condition at the coal mine area.
基金the National Natural Science Foundation of China ! 29772039
文摘Two new iridoid glucosides, serratoside A and serratoside B, were isolated from the aerial parts of Clerodendrum serratum var. amplexifolium Moldenke. Their structures were elucidated by spectral and chemical methods.
文摘Burn-up measurement on an irradiated mixed oxide (MOX) test fuel pellet was carried out through measurements on the dissolver solution by HPLC-Thermal Ionization Mass Spectrometric (TIMS) technique. The studies carried out using HPLC as well as TIMS for quantification of burn-up value are described. While in one case, both the separation and determination of elements of interest (U, Pu and Nd) were carried out by HPLC;in another case, TIMS technique was used to quantify them from the HPLC separated fractions.The rapid separation procedures developed in our laboratory earlier were employed to isolate pure fractions of the desired elements. The individual lanthanide fission products (La to Eu) were separated from each other using dynamic ion-exchange chromatographic technique whereas uranium and plutonium were separated from each other using reversed phase chromatographic technique. The pure fractions of U, Pu and Nd obtained after HPLC separation procedure for “spiked” and “unspiked” dissolver solutions were used in TIMS measurements for the first time in our laboratory. In TIMS analysis, isotopic abundances of uranium, plutonium and neodymium fractions obtained from HPLC separation procedure on an “unspiked” fuel sample were measured. For the determination of U, Pu and Nd by isotopic dilution mass spectrometric technique (IDMS), known quantities of tracers enriched in 238U, 240Pu and 142Nd were added to the pre-weighed dissolver solution and subjected to HPLC separation procedures. The isotope ratios viz. 142Nd/(145Nd +146Nd), 238U/233U and 240Pu/239Pu in the pertinent “spiked” fractions were subsequently measured by TIMS. The spikes were pre-standardized in our laboratory employing reverse isotopic dilution technique against the standard solutions available in our laboratory (for 238U, 239Pu and 142Nd, standard solutions of 233U, 239Pu (of higher abundance than in the sample) and 150Nd were employed as spikes). The burn-up values from duplicate spiking experiments were computed based on the summation of 145Nd + 146Nd. The concentrations of neodymium, uranium and plutonium were also measured using HPLC with post-column derivatisation technique using aresenazo(III) as the post-column reagent. The atom % burn-up computed from HPLC and TIMS techniques were in good agreement.
基金Supported by the Vice-Prosidency for Research of theUniversity of Cartagena for the financial aid through the Program to Support Research Groups (2012-2013)K.Caballero is sponsored by the National Program for Doctoral Formation Colciencias,567-2012
文摘Objective:To determine the biological effects of essential oils(EOs) isolated from Cymbopogon iiardus,Cymbopogon Jlexuosus and Cvrnbopogon marlinii grown in Colombia against two Lepidoptera larvae,common pests in the oil palm.Methods:Specimens were captured in the field and the antifeedant activity and dermal contact lethality of EOs were measured against Acharia fusca and Euprosterna elaeasa(Lepidoptera:I.imacodidae) at various concentrations 0.002-0.600 μL/cm^3 and 0.002-8 μL/g,respectively.Results:All EOs exhibited strong antifeedant and toxicity activity toward Acharia fusca and Euprosterna elaeasa larvae.Cymbopogon marlinii oil was llie most active againsl both pest insect species,although all tested EOs were better than the synthetic;repellent IR535 on both insects.Conclusions:Colombian EOs have potential for integrated pest management programs in the oil palm industry.
文摘The solutions of the Schrodinger equation with quantum mechanical gravitational potential plus harmonic oscillator potential have been presented using the parametric Nikiforov-Uvarov method. The bound state energy eigen values and the corresponding un-normalized eigen functions are obtained in terms of Laguerre polynomials. Also a special case of the potential has been considered and its energy eigen values are obtained.
基金The financial assistance from CSIR,New Delhi(MLP6000-WP-Ⅲ)
文摘The deterioration of environmental conditions is the major contributory factor to poor health and quality of life that hinders sustainable development in any region.Coal mining is one of the major industries that contribute to the economy of a country but it also impacts the environment.The chemical parameters of the coal,overburden,soil and sediments along with the coal mine drainage(CMD)were investigated in order to understand the overall environmental impact from high sulphur coal mining at northeastern coalfield(India).It was found that the total sulphur content of the coal is noticeably high compared to the overburden(OB)and soil.The volatile matter of the coal is sufficiently high against the high ash content of the soil and overburden.The water samples have a High Electrical Conductivity(EC)and high Total Dissolve Solid(TDS).Lower values of pH,indicate the dissolution of minerals present in the coal as well as other minerals in the mine rejects/overburden.The chemical and nano-mineralogical composition of coal,soil and overburden samples was studied using a High Resolution-Transmission Electron Microscopy(HR-TEM),Energy Dispersive Spectroscopy(EDS),Selected-Area Diffraction(SAED),Field Emission-Scanning Electron Microscopy(FE-SEM)/EDS,X-ray diffraction(XRD),Fourier Transform Infrared Spectroscopy(FTIR),Raman and Ion-Chromatographic analysis,and Mossbauer spectroscopy.From different geochemical analysis it has been found that the mine water sample from Ledo colliery has the lowest pH value of 3.30,Tirap colliery samples have the highest electrical conductivity value of5.40 ms cm^(-1)Both Ledo and Tirap coals have total sulphur contents within the range 3-3.50%.The coal mine water from Tirap colliery(TW-15 B)has high values of Mg^(2+)(450 ppm),and Br^-(227.17 ppm).XRD analysis revealed the presence of minerals including quartz and hematite in the coals.Mineral analysis of coal mine overburden(OB)indicates the presence both of pyrite and marcasite which was also confirmed in XRD and Mossbauer spectral analysis.The presented data of the minerals and ultra/nano-particles present shows their ability to control the mobility of hazardous elements,suggesting possible use in environmental management technology,including restoration of the delicate Indian coal mine areas.
基金This study was supported by the financial support from the Korea Institute of Energy Technology Evaluation and Planning(KETEP)grant funded by the Korea government(MOTIE)(20214000000500,training program of CCUS for the green growth)This work was supported by the National Research Foundation of Korea(NRF)grant funded by the Korea government,Ministry of Science and ICT(MSIT)(2020M3D1A2102837).
文摘A rational regulation of the solar water splitting reaction pathway by adjusting the surface composition and phase structure of catalysts is a substantial approach to ameliorate the sluggish reaction kinetics and improve the energy conversion efficiency.In this study,we demonstrate a nanocrystalline iron pyrophosphate(Fe_(4)(P_(2)O_(7))_(3),FePy)-regulated hybrid overlayer with amorphous iron phosphate(FePO_(4),FePi)on the surface of metal oxide nanostructure with boosted photoelectrochemical(PEC)water oxidation.By manipulating the facile electrochemical surface treatment followed by the phosphating process,nanocrystalline FePy is localized in the FePi amorphous overlayer to form a heterogeneous hybrid structure.The FePy-regulated hybrid overlayer(FePy@FePi)results in significantly enhanced PEC performance with long-term durability.Compared with the homogeneous FePi amorphous overlayer,FePy@FePi can improve the charge transfer efficiency more significantly,from 60% of FePi to 79%of FePy@FePi.Our density-functional theory calculations reveal that the coexistence of FePi and FePy phases on the surface of metal oxide results in much better oxygen evolution reaction kinetics,where the FePi was found to have a typical down-hill reaction for the conversion from OH*to O_(2),while FePy has a low free energy for the formation of OH*.
