The mass energy absorption coefficient (len=q), effective atomic number (ZPEAeff ), and electron density (NPEAeff ) of some biomolecules with potential application in radiation dosimetry were calculated for their phot...The mass energy absorption coefficient (len=q), effective atomic number (ZPEAeff ), and electron density (NPEAeff ) of some biomolecules with potential application in radiation dosimetry were calculated for their photon energy absorption (PEA) in the energy region of 1–20 MeV. It was noticed that the values of len=q, ZPEAeff , and NPEAeff vary with the energy and composition of the biomolecules. The results for ZPEAeff were compared with effective atomic numbers (ZPIeff ) owing to the photon interaction (PI). Significant differences were noted between ZPEAeff and ZPIeff in the energy region of 10–150 keV for all of the biomolecules involved. A maximum difference of 45.36% was observed at 50 keV for creatinine hydrochloride. Moreover, the studied attenuation parameters were found to be sharply affected at the K-absorption edge of relatively high-Z elements present in the biomolecules.展开更多
Objective:To investigate the effect of oxidized transitional metal(ferric and cupric) ions on the amino acids.Methods:25 mmol/L hydroxyproline and 25 mmol/L histidine were incubated with 50μL Fe<sup>3+</su...Objective:To investigate the effect of oxidized transitional metal(ferric and cupric) ions on the amino acids.Methods:25 mmol/L hydroxyproline and 25 mmol/L histidine were incubated with 50μL Fe<sup>3+</sup> and Cu<sup>2+</sup> ions at pH 7.4 and 37℃for 30 mins in separate test tubes.Then 500μL of 1% thiobarbituricacid(TBA) was added to the incubated amino acids followed by addition of 500μL of glacial acetic acid.The resultant mixture was vortexed and heated at 100℃for 30 min.Absorbance readings were noted after cooling to room temperature.The experiment was repeated in the presence of various reagents,like hydroxyl radical scavengers,antioxidant enzymes,and reducing agents and metal ion chelators.Results:The pink chromogen formed with the absorbance maxima at 524 nm,AND shifted to 560 nm in alkaline pH.The absorbance was expressed as TBAadduct in MDA units.The TBA-adduct decreased in the presence of reducing agents and metal ion chelators.Antioxidant enzymes and hydroxyl radical scavengers did not show any effect. Conclusion:Transitional metal ions in their oxidized state showed significant damage to amino acids,hydroxyproline and histidine.The results indicate the possible role played by high-valent oxo-iron species,ferryl and perferry radicals in damaging biomolecules.展开更多
In the present work, effect of the attraction terms of four recently modified Peng-Robinson (MPR) equations of state on the prediction of solubility of caffeine, cholesterol, uracil and erythromycin was studied. The...In the present work, effect of the attraction terms of four recently modified Peng-Robinson (MPR) equations of state on the prediction of solubility of caffeine, cholesterol, uracil and erythromycin was studied. The attraction terms of two of these equations are linear relative to the acentric factor and for the other two are exponential. It is found that the later show less deviation. Also interaction parameters for the studied systems are obtained and the percentage of average absolute relative deviation (%AARD) in each calculation is displayed.展开更多
This study evaluated the effects of purified paper wasp Ropalidia marginata venoms on various biomolecules in the blood serum of albino mice. Changes in the concentration of some important macromolecules, i.e., protei...This study evaluated the effects of purified paper wasp Ropalidia marginata venoms on various biomolecules in the blood serum of albino mice. Changes in the concentration of some important macromolecules, i.e., proteins, free amino acids, uric acid, cholesterol, pyruvic acid, total lipids and glucose were noted down. These alterations were measured after intraperitoneal injection of 40% and 80% 24-hour LD50 purified Ropalidia marginata venom toxin. Serum total protein levels were found to decrease to 78% after 6 hrs, while serum free amino acid levels were significantly increased to 117% 6 hrs after venom injection compared to control. It was also found that serum uric acid levels increased to 138% after 8 hrs of venom injection compared to control. The increase in serum cholesterol i.e. (101% and 106%) and pyruvic acid increased significantly to a maximum value of 106% after 6 hrs of treatment at 40% LD<sub>50</sub>. Glycogen levels in the gastrocnemius muscle were found to decrease significantly (p-0.05) to 43% and 92% at LD<sub>50</sub> after injection of purified Ropalidia marginata venom after 8 h and 80% at LD<sub>50</sub> compared to control. Moreover, up to 71% and 81% were obtained at 10 hrs of treatment with the same dose. In the present study, the purified toxins significantly changed the levels of biomolecules in blood serum, indicating their wider effects on cellular physiology due to toxic effects and stress on the animal. These toxins can be good antigens and stimulate immune responses in experimental mice.展开更多
Single cylindrical submicron pores in PMMA polymer membranes are micropatterned by electron beam lithography and integrated into all PMMA-based electrophoretic flow detector systems. Pore dimensions are 450 nm in diam...Single cylindrical submicron pores in PMMA polymer membranes are micropatterned by electron beam lithography and integrated into all PMMA-based electrophoretic flow detector systems. Pore dimensions are 450 nm in diameter and 1 μm in length. The pores are electrically characterized in aqueous KCl electrolyte, exhibiting a stable time-independent ionic current through the pore with a noise level of less than 1% of the open-pore current. The current-voltage curves are linear and scale with electrolyte concentration. The negative surface charge of the membrane over-proportionally decreases pore conductance at low electrolyte concentrations (≤0.1 M) that are still beyond those typically applied in biological experiments. Pores do not exhibit rectification of current flowing through them, allowing for operation with either polarity. To allow for detection of yet much smaller particles, the described PMMA-based system also was successfully equipped with pores of 1.5 nm instead of 450 nm in diameter. This was achieved by introducing naturally occurring biological protein pores of α-hemolysin on a lipid bilayer into the prepatterned PMMA membrane of an assembled PMMA-based electrophoretic flow detector system. Characteristics of translocation events of single-stranded linear plasmid DNA molecules through the pores were recorded, and ionic current deductions during biomolecule translocation were clear and distinguished. Based on the presented submicron scale open pore ionic current transport properties, as well as the observed passage of DNA molecules through protein pores inserted into PMMA membranes, our current research proposes that all PMMA electrophoretic flow detectors exhibit an excellent potential for future use as biomedical resistive-pulse sensors, as long as pore dimensions match those of biomolecules to be detected.展开更多
Mesophilic biogas production and substrate decomposition is one of the significant limiting steps in biogas generation. The rate of generation and quality often affect the viability of biogas systems. This study asses...Mesophilic biogas production and substrate decomposition is one of the significant limiting steps in biogas generation. The rate of generation and quality often affect the viability of biogas systems. This study assessed the potential for biogas process catalysis using powdered Sorghum bicolor L., Zea mays, and Pennisetum glaucum. The kinetics and biogas generation processes were studied. Experiments were conducted in 1 m<sup>3</sup> tubular batch reactors, where batches were dosed with various organic biomolecules. Results show that the use of P. glaucum L. and S. bicolor L. reduced the biogas retention times significantly. Biogas generation commenced after the first day for digesters fed with S. bicolor L. and P. glaucum L. while one with Z. mays and control occurred on day two. The rate of biomethanation and methane content were enhanced. S. bicolor L. led to the highest methane content. Findings reveal that locally available organic biomolecules improved biogas quality and quantity.展开更多
Insoluble fatty surfaces are involved in many important interactions such as in biomembranes with soluble biological macro and micromolecules. In this paper we have studied the adsorption interaction of aqueous soluti...Insoluble fatty surfaces are involved in many important interactions such as in biomembranes with soluble biological macro and micromolecules. In this paper we have studied the adsorption interaction of aqueous solution of DNA, some proteins and lactose on several sparingly soluble fatty substances namely milk fat, stearic acid, palmitic acid, phosphatidyl choline and cholesterol surfaces by measuring the depletion of the adsorbates by analytical methods. Adsorption () of DNA on the soft surfaces of stearic acid, milk fat, phosphatidyl choline, palmitic acid and cholesterol was measured as a function of DNA concentration C2. In each case was found to increase with C2 until it reached the maximum value at a critical concentration . For different surfaces stands in the order: stearic acid > milk fat > phosphatidyl choline > cholesterol > palmitic acid. DNA forms multilayers on stearic acid surface. Adsorption of hemoglobin on cholesterol surface is found to be negative or zero but that of BSA on cholesterol is positive. Adsorption of gelatin on cholesterol surface is significantly higher than that of BSA. Lysozyme on cholesterol surface forms multilayers and on casein forms bilayer. The lowering of free energies ?DGo for all systems have been calculated using integrated form of the Gibbs adsorption and their values have been compared with each other. It is concluded that despite differences in the adsorption behavior of the biomolecules on various soft surfaces, free energy change expressed as Bull’s free energy change (Δ) remain nearly constant except for BSA-fatty acid interaction which may be likely due a specific interaction.展开更多
We investigate the properties of the excess charge(electron, hole) introduced into a two-strand biomolecule. We consider the possibility that the stable soliton excitation can be formed due to interaction of excess ch...We investigate the properties of the excess charge(electron, hole) introduced into a two-strand biomolecule. We consider the possibility that the stable soliton excitation can be formed due to interaction of excess charge with the phonon subsystem. The influence of overlap of the molecular orbitals between adjacent structure elements of the macromolecular chain on the soliton properties is discussed. Special attention is paid to the influence of the overlapping of the molecular orbitals between structure elements placed on the different chains. Using the literature values of the basic energy parameters of the two-chain biomolecular structures, possible types of soliton solutions are discussed.展开更多
In view of its potent microbicidal actions, ozone (O3) offers much potential for application as a therapeutic agent in oral health, e.g. in the treatment of dental caries. This oxidant is extremely reactive towards bi...In view of its potent microbicidal actions, ozone (O3) offers much potential for application as a therapeutic agent in oral health, e.g. in the treatment of dental caries. This oxidant is extremely reactive towards biomolecules present in the oral environment, and in this study we have employed high-resolution proton (1H) nuclear magnetic resonance (NMR) spectroscopy to determine the nature and extent of the oxidation of biomolecules known to be present in carious dentin, plaque and saliva. Phosphate-buffered (pH 7.00) aqueous solutions containing sodium pyruvate, α-D-glucose, L-cys teine and L-methionine (5.00 mM) were treated with gaseous O3 (4.48 mmol.) delivered by a therapeutic O3 generating device. Attack of O3 on methionine and cysteine generated the corresponding primary oxidation products of these substrates, specifically methionine sulphoxide [98% ± 4% (mean ± SEM) yield] and cystine (95% ± 6% yield) respectively, and treatment of pyruvate with this oxidant produced acetate and CO2 via an oxidative decarboxylation process (93% ± 4% yield). Reaction of O3 with α-D-glucose gave rise to formate as a major product (24% ± 2% yield). In conclusion, multicomponent 1H NMR analysis of appropriate chemical model systems provides valuable molecular information regarding the reactivity of O3 towards biomolecules present in the oral environment, information which is of much relevance to its therapeutic mechanisms of action. Moreover, in view of the much higher concentrations of these O3-scavenging biomolecules in oral fluid and/or soft tissue environments than that of O3 applied, they may also serve to offer protection against putative adverse effects inducible by any of this oxidant which escapes from its site of therapeutic application (e.g., at primary root carious lesions).展开更多
The Group on Protein Mechanics and Evolution at the CAS-MPG Partner Institute for Computational Biology,Shanghai,was established in January 2007 and headed by Dr.Frauke Gr?ter.The Klaus Tschira Lab has continued the e...The Group on Protein Mechanics and Evolution at the CAS-MPG Partner Institute for Computational Biology,Shanghai,was established in January 2007 and headed by Dr.Frauke Gr?ter.The Klaus Tschira Lab has continued the eff orts of this former Independent Junior Research Group,since Dr.Gr?ter took up a position at the Heidelberg Institute of Theoretical Studies(HITS)in Heidelberg,Germany。展开更多
Organic matter is crucial in aerosol-climate interactions,yet the physicochemical properties and origins of organic aerosols remain poorly understood.Here we show the seasonal characteristics of submicron organic aero...Organic matter is crucial in aerosol-climate interactions,yet the physicochemical properties and origins of organic aerosols remain poorly understood.Here we show the seasonal characteristics of submicron organic aerosols in Arctic Svalbard during spring and summer,emphasizing their connection to transport patterns and particle size distribution.Microbial-derived organic matter(MOM)and terrestrial-derived organic matter(TOM)accounted for over 90%of the total organic mass in Arctic aerosols during these seasons,comprising carbohydrate/protein-like and lignin/tannin-like compounds,respectively.In spring,aerosols showed high TOM and low MOM intensities due to biomass-burning influx in the central Arctic.In contrast,summer exhibited elevated MOM intensity,attributed to the shift in predominant atmospheric transport from the central Arctic to the biologically active Greenland Sea.MOM and TOM were associated with Aitken mode particles(<100 nm diameter)and accumulation mode particles(>100 nm diameter),respectively.This association is linked to the molecular size of biomolecules,impacting the number concentrations of corresponding aerosol classes.These findings highlight the importance of considering seasonal atmospheric transport patterns and organic source-dependent particle size distributions in assessing aerosol properties in the changing Arctic.展开更多
Because of their easy tunability in structure,porosity,and micro-environment,metal-organic frameworks(MOFs)have recently attracted numerous attentions in various fields.The detection of ascorbic acid(AA),dopamine(DA),...Because of their easy tunability in structure,porosity,and micro-environment,metal-organic frameworks(MOFs)have recently attracted numerous attentions in various fields.The detection of ascorbic acid(AA),dopamine(DA),and uric acid(UA)is of great significance not only in biomedicine and neurochemistry but also in disease diagnosis and pathology research.Herein,a series of bimetallic-organic frameworks,MIL-125(Ti-Fe)-x%NH_(2)(x=0,25,50,75,and 100),was successfully synthesized.MIL-125(Ti-Fe)-x%NH_(2)family was employed as electrochemical sensors for the detection of AA,DA,and UA,and MIL-125(Ti-Fe)-100%NH_(2)exhibited the most promising performance with 50%carbon black doping in 0.1 mol·L^(-1)PBS(pH=7.10).In addition,the as-prepared MIL-125(Ti-Fe)-100%NH_(2)/GCE exhibited excellent anti-interference performance and good stability,which provided a promising platform for future utilization in real sample analysis.展开更多
文摘The mass energy absorption coefficient (len=q), effective atomic number (ZPEAeff ), and electron density (NPEAeff ) of some biomolecules with potential application in radiation dosimetry were calculated for their photon energy absorption (PEA) in the energy region of 1–20 MeV. It was noticed that the values of len=q, ZPEAeff , and NPEAeff vary with the energy and composition of the biomolecules. The results for ZPEAeff were compared with effective atomic numbers (ZPIeff ) owing to the photon interaction (PI). Significant differences were noted between ZPEAeff and ZPIeff in the energy region of 10–150 keV for all of the biomolecules involved. A maximum difference of 45.36% was observed at 50 keV for creatinine hydrochloride. Moreover, the studied attenuation parameters were found to be sharply affected at the K-absorption edge of relatively high-Z elements present in the biomolecules.
文摘Objective:To investigate the effect of oxidized transitional metal(ferric and cupric) ions on the amino acids.Methods:25 mmol/L hydroxyproline and 25 mmol/L histidine were incubated with 50μL Fe<sup>3+</sup> and Cu<sup>2+</sup> ions at pH 7.4 and 37℃for 30 mins in separate test tubes.Then 500μL of 1% thiobarbituricacid(TBA) was added to the incubated amino acids followed by addition of 500μL of glacial acetic acid.The resultant mixture was vortexed and heated at 100℃for 30 min.Absorbance readings were noted after cooling to room temperature.The experiment was repeated in the presence of various reagents,like hydroxyl radical scavengers,antioxidant enzymes,and reducing agents and metal ion chelators.Results:The pink chromogen formed with the absorbance maxima at 524 nm,AND shifted to 560 nm in alkaline pH.The absorbance was expressed as TBAadduct in MDA units.The TBA-adduct decreased in the presence of reducing agents and metal ion chelators.Antioxidant enzymes and hydroxyl radical scavengers did not show any effect. Conclusion:Transitional metal ions in their oxidized state showed significant damage to amino acids,hydroxyproline and histidine.The results indicate the possible role played by high-valent oxo-iron species,ferryl and perferry radicals in damaging biomolecules.
文摘In the present work, effect of the attraction terms of four recently modified Peng-Robinson (MPR) equations of state on the prediction of solubility of caffeine, cholesterol, uracil and erythromycin was studied. The attraction terms of two of these equations are linear relative to the acentric factor and for the other two are exponential. It is found that the later show less deviation. Also interaction parameters for the studied systems are obtained and the percentage of average absolute relative deviation (%AARD) in each calculation is displayed.
文摘This study evaluated the effects of purified paper wasp Ropalidia marginata venoms on various biomolecules in the blood serum of albino mice. Changes in the concentration of some important macromolecules, i.e., proteins, free amino acids, uric acid, cholesterol, pyruvic acid, total lipids and glucose were noted down. These alterations were measured after intraperitoneal injection of 40% and 80% 24-hour LD50 purified Ropalidia marginata venom toxin. Serum total protein levels were found to decrease to 78% after 6 hrs, while serum free amino acid levels were significantly increased to 117% 6 hrs after venom injection compared to control. It was also found that serum uric acid levels increased to 138% after 8 hrs of venom injection compared to control. The increase in serum cholesterol i.e. (101% and 106%) and pyruvic acid increased significantly to a maximum value of 106% after 6 hrs of treatment at 40% LD<sub>50</sub>. Glycogen levels in the gastrocnemius muscle were found to decrease significantly (p-0.05) to 43% and 92% at LD<sub>50</sub> after injection of purified Ropalidia marginata venom after 8 h and 80% at LD<sub>50</sub> compared to control. Moreover, up to 71% and 81% were obtained at 10 hrs of treatment with the same dose. In the present study, the purified toxins significantly changed the levels of biomolecules in blood serum, indicating their wider effects on cellular physiology due to toxic effects and stress on the animal. These toxins can be good antigens and stimulate immune responses in experimental mice.
文摘Single cylindrical submicron pores in PMMA polymer membranes are micropatterned by electron beam lithography and integrated into all PMMA-based electrophoretic flow detector systems. Pore dimensions are 450 nm in diameter and 1 μm in length. The pores are electrically characterized in aqueous KCl electrolyte, exhibiting a stable time-independent ionic current through the pore with a noise level of less than 1% of the open-pore current. The current-voltage curves are linear and scale with electrolyte concentration. The negative surface charge of the membrane over-proportionally decreases pore conductance at low electrolyte concentrations (≤0.1 M) that are still beyond those typically applied in biological experiments. Pores do not exhibit rectification of current flowing through them, allowing for operation with either polarity. To allow for detection of yet much smaller particles, the described PMMA-based system also was successfully equipped with pores of 1.5 nm instead of 450 nm in diameter. This was achieved by introducing naturally occurring biological protein pores of α-hemolysin on a lipid bilayer into the prepatterned PMMA membrane of an assembled PMMA-based electrophoretic flow detector system. Characteristics of translocation events of single-stranded linear plasmid DNA molecules through the pores were recorded, and ionic current deductions during biomolecule translocation were clear and distinguished. Based on the presented submicron scale open pore ionic current transport properties, as well as the observed passage of DNA molecules through protein pores inserted into PMMA membranes, our current research proposes that all PMMA electrophoretic flow detectors exhibit an excellent potential for future use as biomedical resistive-pulse sensors, as long as pore dimensions match those of biomolecules to be detected.
文摘Mesophilic biogas production and substrate decomposition is one of the significant limiting steps in biogas generation. The rate of generation and quality often affect the viability of biogas systems. This study assessed the potential for biogas process catalysis using powdered Sorghum bicolor L., Zea mays, and Pennisetum glaucum. The kinetics and biogas generation processes were studied. Experiments were conducted in 1 m<sup>3</sup> tubular batch reactors, where batches were dosed with various organic biomolecules. Results show that the use of P. glaucum L. and S. bicolor L. reduced the biogas retention times significantly. Biogas generation commenced after the first day for digesters fed with S. bicolor L. and P. glaucum L. while one with Z. mays and control occurred on day two. The rate of biomethanation and methane content were enhanced. S. bicolor L. led to the highest methane content. Findings reveal that locally available organic biomolecules improved biogas quality and quantity.
文摘Insoluble fatty surfaces are involved in many important interactions such as in biomembranes with soluble biological macro and micromolecules. In this paper we have studied the adsorption interaction of aqueous solution of DNA, some proteins and lactose on several sparingly soluble fatty substances namely milk fat, stearic acid, palmitic acid, phosphatidyl choline and cholesterol surfaces by measuring the depletion of the adsorbates by analytical methods. Adsorption () of DNA on the soft surfaces of stearic acid, milk fat, phosphatidyl choline, palmitic acid and cholesterol was measured as a function of DNA concentration C2. In each case was found to increase with C2 until it reached the maximum value at a critical concentration . For different surfaces stands in the order: stearic acid > milk fat > phosphatidyl choline > cholesterol > palmitic acid. DNA forms multilayers on stearic acid surface. Adsorption of hemoglobin on cholesterol surface is found to be negative or zero but that of BSA on cholesterol is positive. Adsorption of gelatin on cholesterol surface is significantly higher than that of BSA. Lysozyme on cholesterol surface forms multilayers and on casein forms bilayer. The lowering of free energies ?DGo for all systems have been calculated using integrated form of the Gibbs adsorption and their values have been compared with each other. It is concluded that despite differences in the adsorption behavior of the biomolecules on various soft surfaces, free energy change expressed as Bull’s free energy change (Δ) remain nearly constant except for BSA-fatty acid interaction which may be likely due a specific interaction.
基金Project supported by the Ministry of Education,Science and Technological Development of the Republic of Serbiathe Ministry of Science and Higher Education of the Russian Federation in the framework of Increase Competitiveness Program of NUST “MISiS” (Grant No.K2-2019-010)the Project within the Cooperation Agreement between the JINR,Dubna,Russian Federation and Ministry of Education and Science of the Republic of Serbia。
文摘We investigate the properties of the excess charge(electron, hole) introduced into a two-strand biomolecule. We consider the possibility that the stable soliton excitation can be formed due to interaction of excess charge with the phonon subsystem. The influence of overlap of the molecular orbitals between adjacent structure elements of the macromolecular chain on the soliton properties is discussed. Special attention is paid to the influence of the overlapping of the molecular orbitals between structure elements placed on the different chains. Using the literature values of the basic energy parameters of the two-chain biomolecular structures, possible types of soliton solutions are discussed.
文摘In view of its potent microbicidal actions, ozone (O3) offers much potential for application as a therapeutic agent in oral health, e.g. in the treatment of dental caries. This oxidant is extremely reactive towards biomolecules present in the oral environment, and in this study we have employed high-resolution proton (1H) nuclear magnetic resonance (NMR) spectroscopy to determine the nature and extent of the oxidation of biomolecules known to be present in carious dentin, plaque and saliva. Phosphate-buffered (pH 7.00) aqueous solutions containing sodium pyruvate, α-D-glucose, L-cys teine and L-methionine (5.00 mM) were treated with gaseous O3 (4.48 mmol.) delivered by a therapeutic O3 generating device. Attack of O3 on methionine and cysteine generated the corresponding primary oxidation products of these substrates, specifically methionine sulphoxide [98% ± 4% (mean ± SEM) yield] and cystine (95% ± 6% yield) respectively, and treatment of pyruvate with this oxidant produced acetate and CO2 via an oxidative decarboxylation process (93% ± 4% yield). Reaction of O3 with α-D-glucose gave rise to formate as a major product (24% ± 2% yield). In conclusion, multicomponent 1H NMR analysis of appropriate chemical model systems provides valuable molecular information regarding the reactivity of O3 towards biomolecules present in the oral environment, information which is of much relevance to its therapeutic mechanisms of action. Moreover, in view of the much higher concentrations of these O3-scavenging biomolecules in oral fluid and/or soft tissue environments than that of O3 applied, they may also serve to offer protection against putative adverse effects inducible by any of this oxidant which escapes from its site of therapeutic application (e.g., at primary root carious lesions).
文摘The Group on Protein Mechanics and Evolution at the CAS-MPG Partner Institute for Computational Biology,Shanghai,was established in January 2007 and headed by Dr.Frauke Gr?ter.The Klaus Tschira Lab has continued the eff orts of this former Independent Junior Research Group,since Dr.Gr?ter took up a position at the Heidelberg Institute of Theoretical Studies(HITS)in Heidelberg,Germany。
基金National Research Foundation(NRF)of Korea NRF-2021M1A5A1065425(KOPRI-PN24011)The FT-ICR MS analysis was supported by the Korea Basic Science Institute under the R&D program(Project No.C330430)supervised by the Ministry of Science and ICT.
文摘Organic matter is crucial in aerosol-climate interactions,yet the physicochemical properties and origins of organic aerosols remain poorly understood.Here we show the seasonal characteristics of submicron organic aerosols in Arctic Svalbard during spring and summer,emphasizing their connection to transport patterns and particle size distribution.Microbial-derived organic matter(MOM)and terrestrial-derived organic matter(TOM)accounted for over 90%of the total organic mass in Arctic aerosols during these seasons,comprising carbohydrate/protein-like and lignin/tannin-like compounds,respectively.In spring,aerosols showed high TOM and low MOM intensities due to biomass-burning influx in the central Arctic.In contrast,summer exhibited elevated MOM intensity,attributed to the shift in predominant atmospheric transport from the central Arctic to the biologically active Greenland Sea.MOM and TOM were associated with Aitken mode particles(<100 nm diameter)and accumulation mode particles(>100 nm diameter),respectively.This association is linked to the molecular size of biomolecules,impacting the number concentrations of corresponding aerosol classes.These findings highlight the importance of considering seasonal atmospheric transport patterns and organic source-dependent particle size distributions in assessing aerosol properties in the changing Arctic.
基金the Natural Science Foundation of Science and Technology Department of Jilin Province(grant No.20210101131JC)the Fundamental Research Funds for the Central Universities(grant No.2412020FZ009 and 2412022ZD048)
文摘Because of their easy tunability in structure,porosity,and micro-environment,metal-organic frameworks(MOFs)have recently attracted numerous attentions in various fields.The detection of ascorbic acid(AA),dopamine(DA),and uric acid(UA)is of great significance not only in biomedicine and neurochemistry but also in disease diagnosis and pathology research.Herein,a series of bimetallic-organic frameworks,MIL-125(Ti-Fe)-x%NH_(2)(x=0,25,50,75,and 100),was successfully synthesized.MIL-125(Ti-Fe)-x%NH_(2)family was employed as electrochemical sensors for the detection of AA,DA,and UA,and MIL-125(Ti-Fe)-100%NH_(2)exhibited the most promising performance with 50%carbon black doping in 0.1 mol·L^(-1)PBS(pH=7.10).In addition,the as-prepared MIL-125(Ti-Fe)-100%NH_(2)/GCE exhibited excellent anti-interference performance and good stability,which provided a promising platform for future utilization in real sample analysis.