The sequestration of^(99)Tc represents one of the most challenging tasks in nuclear waste decontamination In the event of a radioactive waste leak,^(99)TcO_(4)^(-)(a main form of^(99)Tc)would spread into the groundwa ...The sequestration of^(99)Tc represents one of the most challenging tasks in nuclear waste decontamination In the event of a radioactive waste leak,^(99)TcO_(4)^(-)(a main form of^(99)Tc)would spread into the groundwa ter,a scenario difficult to address with conventional anion exchange materials like resin and inorganic cationic sorbents.Herein,we present a nickel(II)metal-organic framework(MOF),TNU-143,featuring3D four-fold interpenetrated networks.TNU-143 exhibits efficient ReO_(4)^(-)(a nonradioactive analogue o^(99)TcO_(4)^(–))removal with fast anion exchange kinetics(<1 min),high sorption capacity(844 mg/g for ReO_(4)^(-))and outstanding selectivity over common anions.More importantly,TNU-143 shows superior stability in alkaline solution and can remove 91.6%ReO_(4)^(-)from simulated alkaline high-level waste(HLW)stream with solid-liquid ratio of 40 g/L.The uptake mechanism is elucidated by the single-crystal structure o TNU-143(Re),showing that ReO_(4)^(-)anions are firmly coordinated to nickel cation to result in a 2D lay ered structures.Density functional theory(DFT)calculations confirm the transformation from TNU-143 to TNU-143(Re)is a thermodynamically favorable process.This work presents a new approach to the removal of Re O_(4)^(-)/^(99)TcO_(4)^(-)from alkaline nulcear fuel using MOF sorbents.展开更多
BACKGROUND When interpreting nuclear medicine images,unexpected findings are sometimes encountered.Recognizing these findings and determining the mechanism of their occurrence could have a significant impact on early ...BACKGROUND When interpreting nuclear medicine images,unexpected findings are sometimes encountered.Recognizing these findings and determining the mechanism of their occurrence could have a significant impact on early diagnosis of critical diseases and the appropriate management of patients.CASE SUMMARY A 59-year-old man was admitted to the emergency room due to left hemiparesis,left hemifacial palsy,and mild dysarthria.After 2 wk of hospitalization,the patient complained of dry eyes and mouth.Thus,salivary scintigraphy was performed to evaluate the functional status of his salivary glands.Incidental accumulation in the right frontoparietal area was found on salivary scintigraphy.Fluid-attenuated inversion recovery phase magnetic resonance(FLAIR phase MR)image showed diffuse high signal intensity in the same area.Anterior and posterior horns of the right lateral ventricle were obliterated and the midline was slightly shifted to the left side due to right frontoparietal swelling.On salivary scintigraphy,Tc-99m pertechnetate was incidentally accumulated in a subacute cerebral infarction lesion.Two years after the diagnosis of acute infarction,the second series of salivary scintigraphy showed no abnormal activity in the brain.FLAIR phase MR image also demonstrated markedly decreased high signal intensity in the previous infarction lesion without evidence of swelling indicating chronic cerebral infarction.CONCLUSION This case highlights that Tc-99m pertechnetate could accumulate in a subacute cerebral infarction lesion.The mechanism of an unexpected uptake of Tc-99m pertechnetate in unusual sites should be evaluated and kept in mind for better interpretation.展开更多
Over 70%of the treated contaminated water at the Fukushima Daiichi Nuclear Power Station contains radionuclides beyond the regulatory standard for discharge that need to be re-purified.Technetium-99(^(99)Tc),mainly in...Over 70%of the treated contaminated water at the Fukushima Daiichi Nuclear Power Station contains radionuclides beyond the regulatory standard for discharge that need to be re-purified.Technetium-99(^(99)Tc),mainly in the form of pertechnetate Tc(VII)O_(4)^(-),is one of the main sources of long-term radiotoxicity that jeopardizes the environment and human health.Herein,we used a series of dicationic pyridinium(DCP)derivative groups(–Py^(+)C_(n)H_(2n)N^(+)Me_(3),n=2,3,and 5)to modify commercial Reillex 425 resins containing tertiary pyridyl groups to improve the adsorption performance of rhenium(Re,an analog of radioactive Tc)and Tc.As the quaternary pyridinium and ammonium sites in one DCP group can adsorb ReO_(4)^(-) simultaneously,DCP-modified Reillex 425(Reillex-Cn)exhibited high maximum adsorption capacities for Re under neutral conditions.Adsorption capacities reached 344.8,416.7,and 588.2 mg g^(-)1 for Reillex 425-C2,Reillex 425-C3,and Reillex 425-C5,respectively.Intraparticle diffusion of ReO_(4)^(-)/TcO_(4)^(-) in Reillex 425-Cn was verified to be the rate-limiting step of adsorption.However,adsorption can be adjusted by the length of the alkyl spacers between the two positively charged N sites in DCP.–Py^(+)C_(2)H_(4)N^(+)Me_(3) significantly enhanced intraparticle diffusion compared to–Py^(+)C_(5)H_(10)N^(+)Me_(3).The two positive sites in–Py^(+)C_(2)H_(4)N^(+)Me_(3) would be laterally distributed,leading to a smaller steric hindrance for ReO_(4)–/TcO_(4)^(-) transport inside the microporous channels.Meanwhile,the longer alkyl spacers in–Py^(+)C_(5)H_(10)N^(+)Me_(3) formed hydrophobic microphases,repulsing the hydrated ReO_(4)–/TcO_(4)^(-) anions.Thus,the adsorptions of both ReO_(4)^(-) and TcO_(4)^(-) on Reillex 425-C2 were faster than those on Reillex 425-C5.Moreover,Reillex 425-Cn exhibited an exothermic nature,good selectivity,excellent reusability,and strong salinity tolerance.This study provides a simple strategy to enhance the Tc removal performance of adsorbents containing abundant micropores,which implies enormous environmental and economic benefits.展开更多
A seventy eight years old male patient underwent a whole body 18F- FDG PET/CT imaging to diagnose the lesion which was showed in the right lung by a chest X ray test and CT scan before. Besides the intense 18F- FDG up...A seventy eight years old male patient underwent a whole body 18F- FDG PET/CT imaging to diagnose the lesion which was showed in the right lung by a chest X ray test and CT scan before. Besides the intense 18F- FDG uptake of the lesion in the right lung, a lesion in the left parotid gland also showed intense 18F- FDG uptake. To evaluate the pathology of the lesion in the left parotid gland, a parotid gland scintigraphy imaging with Tc-99m pertechnetate was done and revealed a Warthin＇s tumor. Later a fine needle aspiration（FNA） confirmed that it was a Warthin＇s tumor.展开更多
58 children with gastrointestinal bleeding were examined for ectopic gastric mucosa with 99m Tc-pertechnetate. 25 cases who had abnormal uptake in 1 hour were diagnosed positive and among them 17 cases were operated o...58 children with gastrointestinal bleeding were examined for ectopic gastric mucosa with 99m Tc-pertechnetate. 25 cases who had abnormal uptake in 1 hour were diagnosed positive and among them 17 cases were operated on and final pathology diagnoses were made- The results showed that 5cases were Meckel's diverticulum, 8 alimentary duplication aberrations and 4 false positive inclusive of 1 enteric hemangioma and 1 enteric telangiectasia. From the results, duplications were more than Meckel's diverticulum which contained gastric mucosa. False positive can be avoided by using the early uptake phase and twice image in the first hour as diagnostic standard except enteric hemangioma and enteric teiangiectasia.展开更多
The efficient separation of fission products,such as TcO_(4)^(-)and I^(-),holds strategic significance for the management of radioactive wastes and environmental protection.In this study,we propose an ultrafast strate...The efficient separation of fission products,such as TcO_(4)^(-)and I^(-),holds strategic significance for the management of radioactive wastes and environmental protection.In this study,we propose an ultrafast strategy for scalable preparation of a highly quaternized organic network to facilitate efficient and synchronous separation of iodide and pertechnetate.The network can be prepared within a few minutes at room temperature,using polyethylenimine and 1,2,4,5-tetrakis(bromomethyl)benzene as building blocks.After chlorine replacement,the network,abundantly decorated with quaternary ammonium groups(Cl@QPN),exhibits an ultrahigh positive charge density of 7.6 mmol/g.This enables the rapid and efficient enrichment of target anions through strong electrostatic Coulomb interactions.As a result,Cl@QPN exhibits significantly higher adsorption rate constants of 0.830 g/(mg min)for ReO_(4)^(-)(a nonradioactive surrogate of TcO_(4)^(-))and 0.677 g/(mg min)for I-compared to other materials.Furthermore,it possesses high adsorption capacities,reaching 1,681 mg/g for ReO_(4)^(-)and 917.4 mg/g for I-.Cl@QPN also demonstrates good selectivity towards target ions and shows efficient adsorption for^(99)TcO_(4)^(-).Additionally,Cl@QPN exhibits high dynamic processing capacities,handling up to 3,100 and 7,400 kg of simulated streams per kilogram of material for I-and ReO_(4)^(-),respectively.展开更多
Intestinal duplication is an uncommon congenital condition in young adults.A 25-year-old man complained of chronic,intermittent abdominal pain for 3 years following previous appendectomy for the treatment of suspected...Intestinal duplication is an uncommon congenital condition in young adults.A 25-year-old man complained of chronic,intermittent abdominal pain for 3 years following previous appendectomy for the treatment of suspected appendicitis.Abdominal discomfort and pain,suggestive of intestinal obstruction,recurred after operation.A tubular mass was palpable in the right lower quadrant.Computed tomography enterography scan identified suspicious intestinal intussusception,while Tc-99m pertechnetate scintigraphy revealed a cluster of strip-like abnormal radioactivity in the right lower quadrant.On exploratory laparotomy,a tubular-shaped ileal duplication cyst was found arising from the mesenteric margin of the native ileal segment located 15 cm proximal to the ileocecal valve.Ileectomy was performed along with the removal of the duplication disease,and the end-to-end anastomosis was done to restore the gastrointestinal tract continuity.Pathological examination showed ileal duplication with ectopic gastric mucosa.The patient experienced an eventless postoperative recovery and remained asymptomatic within 2 years of postoperative follow-up.展开更多
BACKGROUND Ectopic thyroid is a rare developmental disorder,typically found in lingual areas,and most distantly in the abdomen.Thyroid ectopia in multiple regions is extremely rare.To date,there are no reports of ecto...BACKGROUND Ectopic thyroid is a rare developmental disorder,typically found in lingual areas,and most distantly in the abdomen.Thyroid ectopia in multiple regions is extremely rare.To date,there are no reports of ectopic goiter in four regions of the abdominal cavity in a single patient.CASE SUMMARY We present a case of thyroid ectopia in four areas of the abdomen,comprising normal orthotopic thyroid tissue.A 36-year-old woman,who underwent ovarian teratoma resection 10 years previously due to symptomatic ovarian teratoma,was referred to our hospital for treatment of an incidental hepatic mass.Magnetic resonance imaging and computed tomography(CT)of the abdomen showed a heterogeneously enhanced lobulated lesion in the sixth and seventh hepatic segment adjacent to the diaphragm.The mass was surgically excised,and histologic examination determined an ectopic nodular goiter.At the one-year follow-up,the abdominal CT scan,whole-body radionuclide I131 examination,and abdominal wall biopsy showed similar lesions in the left renal fascia and anterior abdominal wall.CONCLUSION Multiple para-ectopic thyroid is often misdiagnosed,owing to its extremely rare incidence and non-specific clinical manifestations and imaging features.A combination of multiple examinations is necessary for diagnostic accuracy.展开更多
The treatment of anionic ^(99)TcO_(4)^(-)in the waste tank with high alkalinity is still very challenging.In this work,a new temperature-responsive alkaline aqueous biphasic system(ABS)based on(tri-n–butyl)-ntetradec...The treatment of anionic ^(99)TcO_(4)^(-)in the waste tank with high alkalinity is still very challenging.In this work,a new temperature-responsive alkaline aqueous biphasic system(ABS)based on(tri-n–butyl)-ntetradecyl phosphonium chloride(P_(44414)Cl)was developed to remove radioactive ^(99)TcO_(4)^(-).The phase transition mechanism was studied by cloud point titration,small-angel X-ray scattering,dynamic light scattering,and molecular dynamic simulations.As the Na OH concentration or temperature increased,the P_(44414)^(+)micelle could grow and aggregate.This micelle showed a particularly high affinity toward ReO_(4)^(-)/^(99)TcO_(4)^(-)compared to other competing anions and could directly extract more than 98.6%of ^(99)TcO_(4)^(-)from simulated radioactive tank waste supernatant.Furthermore,the loaded ^(99)TcO_(4)^(-)could be easily stripped by using concentrated nitric acid rather than metal salt-based reductants.This work clearly demonstrates that the alkaline ABS is a promising separation system for solving the technetium problem in the alkaline waste tank.展开更多
Low-cost adsorbents, Magnesium ferrite (MgFe2O4) nanoparticles were synthesized using three different types of fuel such as Urea, Oxalic acid, and Citric acid via sol-gel auto-combustion method. The prepared products ...Low-cost adsorbents, Magnesium ferrite (MgFe2O4) nanoparticles were synthesized using three different types of fuel such as Urea, Oxalic acid, and Citric acid via sol-gel auto-combustion method. The prepared products were characterized by means of powder X-Ray Diffraction (XRD), Fourier Transform Infrared spectroscopy (FT-IR) and Field Emission Scanning Electron Microscope (FE-SEM). The influence of the fuel used on the morphology and the crystallite size of MgFe2O4 Nano products were studied. The results showed that Citric acid fuel produced pure MgFe2O4 with the smallest crystallite size average cluster = 13.53 nm. The synthesized sample was used for the removal of 99TcO4- anions from low level liquid waste under studied conditions. The different parameters affecting on the adsorption process using the batch method were studied. The results revealed that MgFe2O4 nanostructure has high removal ability of 99TcO4- from aqueous solutions (98.84%). The adsorption data are in good agreement with Freundlich and Pseudo second order isotherm models. The adsorption process was a chemisorption reaction additionally, the results of the thermodynamic parameters indicated that the adsorption of 99TcO4- on nanostructures was an exothermic and spontaneous process.展开更多
Efficient segregation of TcO_(4)^(-)from high-level radioactive wastes(HLW)is critical for robust nuclear waste management and environmental protection.However,achieving deep decontamination is especially challenging ...Efficient segregation of TcO_(4)^(-)from high-level radioactive wastes(HLW)is critical for robust nuclear waste management and environmental protection.However,achieving deep decontamination is especially challenging in complex conditions of strong basicity,high radiation,and excessively competitive anions.Herein,we addressed the long-term challenge by modifying the imidazolium core with phenyl,trimethylphenyl,and benzyl groups in a flexible polymer chain,which constructs a precisely targeted microenvironment for selective TcO_(4)^(-)capture.This custom-engineered material(SCU-CPN-7)exhibits fast kinetics,high adsorption capacity(314.7 mg/g),excellent distribution coefficient(1.3×10^(7) mL/g),and remarkable efficiency in TcO_(4)^(-)uptake under the combining extreme conditions of strong alkalinity(1 M NaOH)and high radioactivity.More importantly,owing to the synergistic effects of the hydrophobic effect,electrostatic affinity,and p-πinteractions,SCU-CPN-7 demonstrates exceptional selectivity,capable of almost quantificationally removing TcO_(4)^(-)in the coexistence of a large excess of NO_(3)^(-)and SO_(4)^(2-),leading to an unparalleled uptake performance of TcO_(4)^(-)from simulated HLW in both batch and dynamic column separation tests.展开更多
Nuclear energy has long been viewed as a promising alternative to fossil fuel energy.As the main product of^(235)U/^(239)Pu fission in nuclear power plants,~400 metric tons of^(99)Tc have been generated over the past ...Nuclear energy has long been viewed as a promising alternative to fossil fuel energy.As the main product of^(235)U/^(239)Pu fission in nuclear power plants,~400 metric tons of^(99)Tc have been generated over the past few decades[1].^(99)Tc is a longlivedβ-radiation emitter(half-life 2.13×10~5 years)that exists primarily in the form of the pertechnetate ion(^(99)TcO_(4)^(-),containing the Tc(Ⅶ)oxidation state)[2].展开更多
Ionic covalent organic framework(COF)materials with high specific surface areas and well-defined pore structures are desired for many applications yet seldom reported.Herein,we report a cationic pyridinium salt-based ...Ionic covalent organic framework(COF)materials with high specific surface areas and well-defined pore structures are desired for many applications yet seldom reported.Herein,we report a cationic pyridinium salt-based COF(PS-COF-1)with a Brunauer-Emmett-Teller(BET)surface area of 2703 m^(2) g^(-1),state-ofthe-art for an ionic COF.Aided by its ordered pore structure,chemical stability,and radiation resistance,PS-COF-1 showed exceptional adsorption properties toward aqueous ReO_(4)^(-)(1262 mg g^(-1))and ^(99)TcO_(4)^(-).Its adsorption performance surpassed its corresponding amorphous analogue.Importantly,PS-COF-1 exhibited fast adsorption kinetics,high adsorption capacities,and selectivity for ^(99)TcO_(4)^(-)and ReO_(4)^(-)at high ionic strengths,leading to the successful removal of ^(99)TcO_(4)^(-)under conditions relevant to low-activity waste streams at US legacy Hanford nuclear sites.In addition,PS-COF-1 can rapidly decontaminate ReO_(4)^(-)/^(99)TcO_(4)^(-)polluted potable water(~10 ppb)to drinking water level(0 ppb,part per billion)within 10 min.Density functional theory(DFT)calculations revealed PS-COF-1 has a strong affinity for ReO_(4)^(-)and ^(99)TcO_(4)^(-),thereby favoring adsorption of these low charge density anions over other common anions(e.g.,Cl^(-),NO_(3)^(-),SO_(4)^(2-),CO_(3)^(2-)).Our work demonstrates a novel cationic COF sorbent for selective radionuclide capture and legacy nuclear waste management.展开更多
^(99)Tc is a long-lived radionuclide present in large amounts as TcO_(4)^(-)-anion in used nuclear fuel.Its removal from the waste stream is highly desirable because of its interference capability with actinide separa...^(99)Tc is a long-lived radionuclide present in large amounts as TcO_(4)^(-)-anion in used nuclear fuel.Its removal from the waste stream is highly desirable because of its interference capability with actinide separation and its volatile nature during the nuclear waste vitrification process.Despite the progress achieved in the past few years,the design of anion-exchange materials with optimized Tc uptake property and improved stability under the extreme condition is still a research goal beneficial for reducing the volume of secondary radioactive solid waste generated during the waste partitioning process.However,their design philosophy remains elusive,with challenges coming from charge repulsion,steric hindrance,and insufficient reactive sites within the materials.Herein,we present a design philosophy of cationic polymer network materials for TcO_(4)^(-)separation by systematic precursor screening and structure prediction.This affords an optimized material,SCU-CPN-2(SCU=Soochow University),with extremely high positive charge density while maintaining high radiation resistance.SCU-CPN-2 exhibits a record high adsorption capacity1,467 mg/g towards the surrogate ReO_(4)^(-)compared to all anion-exchange materials reported up to date.In addition to ultrafast adsorption kinetics,SCU-CPN-2 has remarkable selectivity over nitrate and sulfate,and facile recyclability.展开更多
基金supported by National Natural Science Foundation of China(No.22171210)Research Project of Tianjin Education Commission(No.2023KJ182)Tianjin Research Innovation Project for Postgraduate Students(No.2022BKY200)。
文摘The sequestration of^(99)Tc represents one of the most challenging tasks in nuclear waste decontamination In the event of a radioactive waste leak,^(99)TcO_(4)^(-)(a main form of^(99)Tc)would spread into the groundwa ter,a scenario difficult to address with conventional anion exchange materials like resin and inorganic cationic sorbents.Herein,we present a nickel(II)metal-organic framework(MOF),TNU-143,featuring3D four-fold interpenetrated networks.TNU-143 exhibits efficient ReO_(4)^(-)(a nonradioactive analogue o^(99)TcO_(4)^(–))removal with fast anion exchange kinetics(<1 min),high sorption capacity(844 mg/g for ReO_(4)^(-))and outstanding selectivity over common anions.More importantly,TNU-143 shows superior stability in alkaline solution and can remove 91.6%ReO_(4)^(-)from simulated alkaline high-level waste(HLW)stream with solid-liquid ratio of 40 g/L.The uptake mechanism is elucidated by the single-crystal structure o TNU-143(Re),showing that ReO_(4)^(-)anions are firmly coordinated to nickel cation to result in a 2D lay ered structures.Density functional theory(DFT)calculations confirm the transformation from TNU-143 to TNU-143(Re)is a thermodynamically favorable process.This work presents a new approach to the removal of Re O_(4)^(-)/^(99)TcO_(4)^(-)from alkaline nulcear fuel using MOF sorbents.
文摘BACKGROUND When interpreting nuclear medicine images,unexpected findings are sometimes encountered.Recognizing these findings and determining the mechanism of their occurrence could have a significant impact on early diagnosis of critical diseases and the appropriate management of patients.CASE SUMMARY A 59-year-old man was admitted to the emergency room due to left hemiparesis,left hemifacial palsy,and mild dysarthria.After 2 wk of hospitalization,the patient complained of dry eyes and mouth.Thus,salivary scintigraphy was performed to evaluate the functional status of his salivary glands.Incidental accumulation in the right frontoparietal area was found on salivary scintigraphy.Fluid-attenuated inversion recovery phase magnetic resonance(FLAIR phase MR)image showed diffuse high signal intensity in the same area.Anterior and posterior horns of the right lateral ventricle were obliterated and the midline was slightly shifted to the left side due to right frontoparietal swelling.On salivary scintigraphy,Tc-99m pertechnetate was incidentally accumulated in a subacute cerebral infarction lesion.Two years after the diagnosis of acute infarction,the second series of salivary scintigraphy showed no abnormal activity in the brain.FLAIR phase MR image also demonstrated markedly decreased high signal intensity in the previous infarction lesion without evidence of swelling indicating chronic cerebral infarction.CONCLUSION This case highlights that Tc-99m pertechnetate could accumulate in a subacute cerebral infarction lesion.The mechanism of an unexpected uptake of Tc-99m pertechnetate in unusual sites should be evaluated and kept in mind for better interpretation.
基金supported by the National Natural Science Foundation of China(Nos.51803205,11775214,and 21790371)China Scholarship Council(No.201906345006).
文摘Over 70%of the treated contaminated water at the Fukushima Daiichi Nuclear Power Station contains radionuclides beyond the regulatory standard for discharge that need to be re-purified.Technetium-99(^(99)Tc),mainly in the form of pertechnetate Tc(VII)O_(4)^(-),is one of the main sources of long-term radiotoxicity that jeopardizes the environment and human health.Herein,we used a series of dicationic pyridinium(DCP)derivative groups(–Py^(+)C_(n)H_(2n)N^(+)Me_(3),n=2,3,and 5)to modify commercial Reillex 425 resins containing tertiary pyridyl groups to improve the adsorption performance of rhenium(Re,an analog of radioactive Tc)and Tc.As the quaternary pyridinium and ammonium sites in one DCP group can adsorb ReO_(4)^(-) simultaneously,DCP-modified Reillex 425(Reillex-Cn)exhibited high maximum adsorption capacities for Re under neutral conditions.Adsorption capacities reached 344.8,416.7,and 588.2 mg g^(-)1 for Reillex 425-C2,Reillex 425-C3,and Reillex 425-C5,respectively.Intraparticle diffusion of ReO_(4)^(-)/TcO_(4)^(-) in Reillex 425-Cn was verified to be the rate-limiting step of adsorption.However,adsorption can be adjusted by the length of the alkyl spacers between the two positively charged N sites in DCP.–Py^(+)C_(2)H_(4)N^(+)Me_(3) significantly enhanced intraparticle diffusion compared to–Py^(+)C_(5)H_(10)N^(+)Me_(3).The two positive sites in–Py^(+)C_(2)H_(4)N^(+)Me_(3) would be laterally distributed,leading to a smaller steric hindrance for ReO_(4)–/TcO_(4)^(-) transport inside the microporous channels.Meanwhile,the longer alkyl spacers in–Py^(+)C_(5)H_(10)N^(+)Me_(3) formed hydrophobic microphases,repulsing the hydrated ReO_(4)–/TcO_(4)^(-) anions.Thus,the adsorptions of both ReO_(4)^(-) and TcO_(4)^(-) on Reillex 425-C2 were faster than those on Reillex 425-C5.Moreover,Reillex 425-Cn exhibited an exothermic nature,good selectivity,excellent reusability,and strong salinity tolerance.This study provides a simple strategy to enhance the Tc removal performance of adsorbents containing abundant micropores,which implies enormous environmental and economic benefits.
文摘A seventy eight years old male patient underwent a whole body 18F- FDG PET/CT imaging to diagnose the lesion which was showed in the right lung by a chest X ray test and CT scan before. Besides the intense 18F- FDG uptake of the lesion in the right lung, a lesion in the left parotid gland also showed intense 18F- FDG uptake. To evaluate the pathology of the lesion in the left parotid gland, a parotid gland scintigraphy imaging with Tc-99m pertechnetate was done and revealed a Warthin＇s tumor. Later a fine needle aspiration（FNA） confirmed that it was a Warthin＇s tumor.
文摘58 children with gastrointestinal bleeding were examined for ectopic gastric mucosa with 99m Tc-pertechnetate. 25 cases who had abnormal uptake in 1 hour were diagnosed positive and among them 17 cases were operated on and final pathology diagnoses were made- The results showed that 5cases were Meckel's diverticulum, 8 alimentary duplication aberrations and 4 false positive inclusive of 1 enteric hemangioma and 1 enteric telangiectasia. From the results, duplications were more than Meckel's diverticulum which contained gastric mucosa. False positive can be avoided by using the early uptake phase and twice image in the first hour as diagnostic standard except enteric hemangioma and enteric teiangiectasia.
基金supported by the National Natural Science Foundation of China(22176138,22276129)a project funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD)。
文摘The efficient separation of fission products,such as TcO_(4)^(-)and I^(-),holds strategic significance for the management of radioactive wastes and environmental protection.In this study,we propose an ultrafast strategy for scalable preparation of a highly quaternized organic network to facilitate efficient and synchronous separation of iodide and pertechnetate.The network can be prepared within a few minutes at room temperature,using polyethylenimine and 1,2,4,5-tetrakis(bromomethyl)benzene as building blocks.After chlorine replacement,the network,abundantly decorated with quaternary ammonium groups(Cl@QPN),exhibits an ultrahigh positive charge density of 7.6 mmol/g.This enables the rapid and efficient enrichment of target anions through strong electrostatic Coulomb interactions.As a result,Cl@QPN exhibits significantly higher adsorption rate constants of 0.830 g/(mg min)for ReO_(4)^(-)(a nonradioactive surrogate of TcO_(4)^(-))and 0.677 g/(mg min)for I-compared to other materials.Furthermore,it possesses high adsorption capacities,reaching 1,681 mg/g for ReO_(4)^(-)and 917.4 mg/g for I-.Cl@QPN also demonstrates good selectivity towards target ions and shows efficient adsorption for^(99)TcO_(4)^(-).Additionally,Cl@QPN exhibits high dynamic processing capacities,handling up to 3,100 and 7,400 kg of simulated streams per kilogram of material for I-and ReO_(4)^(-),respectively.
文摘Intestinal duplication is an uncommon congenital condition in young adults.A 25-year-old man complained of chronic,intermittent abdominal pain for 3 years following previous appendectomy for the treatment of suspected appendicitis.Abdominal discomfort and pain,suggestive of intestinal obstruction,recurred after operation.A tubular mass was palpable in the right lower quadrant.Computed tomography enterography scan identified suspicious intestinal intussusception,while Tc-99m pertechnetate scintigraphy revealed a cluster of strip-like abnormal radioactivity in the right lower quadrant.On exploratory laparotomy,a tubular-shaped ileal duplication cyst was found arising from the mesenteric margin of the native ileal segment located 15 cm proximal to the ileocecal valve.Ileectomy was performed along with the removal of the duplication disease,and the end-to-end anastomosis was done to restore the gastrointestinal tract continuity.Pathological examination showed ileal duplication with ectopic gastric mucosa.The patient experienced an eventless postoperative recovery and remained asymptomatic within 2 years of postoperative follow-up.
基金Supported by National Natural Science Foundation of China,No.81360220.
文摘BACKGROUND Ectopic thyroid is a rare developmental disorder,typically found in lingual areas,and most distantly in the abdomen.Thyroid ectopia in multiple regions is extremely rare.To date,there are no reports of ectopic goiter in four regions of the abdominal cavity in a single patient.CASE SUMMARY We present a case of thyroid ectopia in four areas of the abdomen,comprising normal orthotopic thyroid tissue.A 36-year-old woman,who underwent ovarian teratoma resection 10 years previously due to symptomatic ovarian teratoma,was referred to our hospital for treatment of an incidental hepatic mass.Magnetic resonance imaging and computed tomography(CT)of the abdomen showed a heterogeneously enhanced lobulated lesion in the sixth and seventh hepatic segment adjacent to the diaphragm.The mass was surgically excised,and histologic examination determined an ectopic nodular goiter.At the one-year follow-up,the abdominal CT scan,whole-body radionuclide I131 examination,and abdominal wall biopsy showed similar lesions in the left renal fascia and anterior abdominal wall.CONCLUSION Multiple para-ectopic thyroid is often misdiagnosed,owing to its extremely rare incidence and non-specific clinical manifestations and imaging features.A combination of multiple examinations is necessary for diagnostic accuracy.
基金supported by the National Natural Science Foundation of China(Nos.21876124,U2032106)Natural Science Foundation of Zhejiang Province(Nos.LR21B060001 and LQ21B070004)。
文摘The treatment of anionic ^(99)TcO_(4)^(-)in the waste tank with high alkalinity is still very challenging.In this work,a new temperature-responsive alkaline aqueous biphasic system(ABS)based on(tri-n–butyl)-ntetradecyl phosphonium chloride(P_(44414)Cl)was developed to remove radioactive ^(99)TcO_(4)^(-).The phase transition mechanism was studied by cloud point titration,small-angel X-ray scattering,dynamic light scattering,and molecular dynamic simulations.As the Na OH concentration or temperature increased,the P_(44414)^(+)micelle could grow and aggregate.This micelle showed a particularly high affinity toward ReO_(4)^(-)/^(99)TcO_(4)^(-)compared to other competing anions and could directly extract more than 98.6%of ^(99)TcO_(4)^(-)from simulated radioactive tank waste supernatant.Furthermore,the loaded ^(99)TcO_(4)^(-)could be easily stripped by using concentrated nitric acid rather than metal salt-based reductants.This work clearly demonstrates that the alkaline ABS is a promising separation system for solving the technetium problem in the alkaline waste tank.
文摘Low-cost adsorbents, Magnesium ferrite (MgFe2O4) nanoparticles were synthesized using three different types of fuel such as Urea, Oxalic acid, and Citric acid via sol-gel auto-combustion method. The prepared products were characterized by means of powder X-Ray Diffraction (XRD), Fourier Transform Infrared spectroscopy (FT-IR) and Field Emission Scanning Electron Microscope (FE-SEM). The influence of the fuel used on the morphology and the crystallite size of MgFe2O4 Nano products were studied. The results showed that Citric acid fuel produced pure MgFe2O4 with the smallest crystallite size average cluster = 13.53 nm. The synthesized sample was used for the removal of 99TcO4- anions from low level liquid waste under studied conditions. The different parameters affecting on the adsorption process using the batch method were studied. The results revealed that MgFe2O4 nanostructure has high removal ability of 99TcO4- from aqueous solutions (98.84%). The adsorption data are in good agreement with Freundlich and Pseudo second order isotherm models. The adsorption process was a chemisorption reaction additionally, the results of the thermodynamic parameters indicated that the adsorption of 99TcO4- on nanostructures was an exothermic and spontaneous process.
基金supported by the National Natural Science Foundation of China(22306136,22176139,22425061,22406137,U2267222,U1967217,12305397)the Natural Science Foundation of Jiangsu(BK20230510)+2 种基金the Sichuan Science and Technology Program(2024YFCY0006)the New Cornerstone Science Foundation through the XPLORER PRIZEthe Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD)。
文摘Efficient segregation of TcO_(4)^(-)from high-level radioactive wastes(HLW)is critical for robust nuclear waste management and environmental protection.However,achieving deep decontamination is especially challenging in complex conditions of strong basicity,high radiation,and excessively competitive anions.Herein,we addressed the long-term challenge by modifying the imidazolium core with phenyl,trimethylphenyl,and benzyl groups in a flexible polymer chain,which constructs a precisely targeted microenvironment for selective TcO_(4)^(-)capture.This custom-engineered material(SCU-CPN-7)exhibits fast kinetics,high adsorption capacity(314.7 mg/g),excellent distribution coefficient(1.3×10^(7) mL/g),and remarkable efficiency in TcO_(4)^(-)uptake under the combining extreme conditions of strong alkalinity(1 M NaOH)and high radioactivity.More importantly,owing to the synergistic effects of the hydrophobic effect,electrostatic affinity,and p-πinteractions,SCU-CPN-7 demonstrates exceptional selectivity,capable of almost quantificationally removing TcO_(4)^(-)in the coexistence of a large excess of NO_(3)^(-)and SO_(4)^(2-),leading to an unparalleled uptake performance of TcO_(4)^(-)from simulated HLW in both batch and dynamic column separation tests.
基金supported by the National Natural Science Foundation of China(22322603,U2167218,22341602,U2341289,U24B20195)funding support from the MacDiarmid Institute for Advanced Materials and Nanotechnology。
文摘Nuclear energy has long been viewed as a promising alternative to fossil fuel energy.As the main product of^(235)U/^(239)Pu fission in nuclear power plants,~400 metric tons of^(99)Tc have been generated over the past few decades[1].^(99)Tc is a longlivedβ-radiation emitter(half-life 2.13×10~5 years)that exists primarily in the form of the pertechnetate ion(^(99)TcO_(4)^(-),containing the Tc(Ⅶ)oxidation state)[2].
基金supported by the National Natural Science Foundation of China(U2167218 and 22006036)the National Key Research and Development Program of China(2017YFA0207002 and 2018YFC1900105)+2 种基金the Science Challenge Project(TZ2016004)the Beijing Outstanding Young Scientist Program(H.Y.and X.W.)the Robert A.Welch Foundation(B-0027)(S.M.)。
文摘Ionic covalent organic framework(COF)materials with high specific surface areas and well-defined pore structures are desired for many applications yet seldom reported.Herein,we report a cationic pyridinium salt-based COF(PS-COF-1)with a Brunauer-Emmett-Teller(BET)surface area of 2703 m^(2) g^(-1),state-ofthe-art for an ionic COF.Aided by its ordered pore structure,chemical stability,and radiation resistance,PS-COF-1 showed exceptional adsorption properties toward aqueous ReO_(4)^(-)(1262 mg g^(-1))and ^(99)TcO_(4)^(-).Its adsorption performance surpassed its corresponding amorphous analogue.Importantly,PS-COF-1 exhibited fast adsorption kinetics,high adsorption capacities,and selectivity for ^(99)TcO_(4)^(-)and ReO_(4)^(-)at high ionic strengths,leading to the successful removal of ^(99)TcO_(4)^(-)under conditions relevant to low-activity waste streams at US legacy Hanford nuclear sites.In addition,PS-COF-1 can rapidly decontaminate ReO_(4)^(-)/^(99)TcO_(4)^(-)polluted potable water(~10 ppb)to drinking water level(0 ppb,part per billion)within 10 min.Density functional theory(DFT)calculations revealed PS-COF-1 has a strong affinity for ReO_(4)^(-)and ^(99)TcO_(4)^(-),thereby favoring adsorption of these low charge density anions over other common anions(e.g.,Cl^(-),NO_(3)^(-),SO_(4)^(2-),CO_(3)^(2-)).Our work demonstrates a novel cationic COF sorbent for selective radionuclide capture and legacy nuclear waste management.
基金supported by the National Natural Science Foundation of China(21790374,21825601,21806117,21906114,22006108)the Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD)the National Key R&D Program of China(2018YFB1900203)。
文摘^(99)Tc is a long-lived radionuclide present in large amounts as TcO_(4)^(-)-anion in used nuclear fuel.Its removal from the waste stream is highly desirable because of its interference capability with actinide separation and its volatile nature during the nuclear waste vitrification process.Despite the progress achieved in the past few years,the design of anion-exchange materials with optimized Tc uptake property and improved stability under the extreme condition is still a research goal beneficial for reducing the volume of secondary radioactive solid waste generated during the waste partitioning process.However,their design philosophy remains elusive,with challenges coming from charge repulsion,steric hindrance,and insufficient reactive sites within the materials.Herein,we present a design philosophy of cationic polymer network materials for TcO_(4)^(-)separation by systematic precursor screening and structure prediction.This affords an optimized material,SCU-CPN-2(SCU=Soochow University),with extremely high positive charge density while maintaining high radiation resistance.SCU-CPN-2 exhibits a record high adsorption capacity1,467 mg/g towards the surrogate ReO_(4)^(-)compared to all anion-exchange materials reported up to date.In addition to ultrafast adsorption kinetics,SCU-CPN-2 has remarkable selectivity over nitrate and sulfate,and facile recyclability.
