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Dynamic Flow Control Strategies of Vehicle SCR Urea Dosing System 被引量:1
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作者 LIN Wei ZHANG Youtong ASIF Malik 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2015年第2期276-284,共9页
Selective Catalyst Reduction(SCR)Urea Dosing System(UDS)directly affects the system accuracy and the dynamic response performance of a vehicle.However,the UDS dynamic response is hard to keep up with the changes o... Selective Catalyst Reduction(SCR)Urea Dosing System(UDS)directly affects the system accuracy and the dynamic response performance of a vehicle.However,the UDS dynamic response is hard to keep up with the changes of the engine's operating conditions.That will lead to low NO_χconversion efficiency or NH_3 slip.In order to optimize the injection accuracy and the response speed of the UDS in dynamic conditions,an advanced control strategy based on an air-assisted volumetric UDS is presented.It covers the methods of flow compensation and switching working conditions.The strategy is authenticated on an UDS and tested in different dynamic conditions.The result shows that the control strategy discussed results in higher dynamic accuracy and faster dynamic response speed of UDS.The inject deviation range is improved from being between-8%and 10%to-4%and 2%and became more stable than before,and the dynamic response time was shortened from 200 ms to 150 ms.The ETC cycle result shows that after using the new strategy the NH_3 emission is reduced by 60%,and the NO_χemission remains almost unchanged.The trade-off between NO_χconversion efficiency and NH_3 slip is mitigated.The studied flow compensation and switching working conditions can improve the dynamic performance of the UDS significantly and make the UDS dynamic response keep up with the changes of the engine's operating conditions quickly. 展开更多
关键词 select catalyst reduction(SCR) urea dosing system(UDS) dynamic flow control strategies
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Vacuum-ultraviolet technology photolysis of aqueous reaction systems for organic pollutants abatement
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作者 Bing Zhang Guoqing Jiang +2 位作者 Wenxin Shi Yanei Xue Wenjun Sun 《Chinese Chemical Letters》 2026年第2期263-273,共11页
Vacuum-ultraviolet(VUV)radiation is high-energy UV radiation with a wavelength of 100-200 nm capable of decomposing/mineralizing hazardous emerging organic pollutants(EPs)in water through direct photolysis and/or by g... Vacuum-ultraviolet(VUV)radiation is high-energy UV radiation with a wavelength of 100-200 nm capable of decomposing/mineralizing hazardous emerging organic pollutants(EPs)in water through direct photolysis and/or by generating reactive free radicals(RFRs)during photolysis.However,due to the unsatisfactory photoelectric conversion rate,strong absorption by oxygen and water molecules,and other characteristics of VUV radiation,its application and development are hindered,leading to misconceptions regarding high energy consumption and insufficient free radical yield.The objectives of our assessment in this review are as follows:The illumination of the photochemical characteristics of VUV and the reactivity of aqueous solutions.Summarization of accurate UV dose and energy evaluation criteria.Comparison and analysis of the photochemical mechanisms and reaction kinetics of different types of EPs via VUV direct photolysis,as well as the interference origins of typical substrates in water for VUV decontamination.We found that quantities typically reported in VUV photochemical reactions of engineered systems are underreported in low-pressure mercury lamp(LPUV)photochemical reactions,especially a quantitative indicator of the species or energy that induces a chemical reaction.The absence of these quantities has made it difficult to assess the fundamental performance of VUV photolysis fully compared with that of UV-C.Some studies have sought to optimize VUV-advanced reduction processes(VUV-ARP)or VUV reactor treatment of these contaminants;however,an abundant evaluation of the reaction origins and processes between VUV-derived main RFRs and reactants(H_(2)O,O_(2),organic matter,inorganic ions,etc.)is essential,cause these scientific elements will provide the possibility to break the application gap for VUV in the field of EPs treating.Overall,the data compilation,analysis,and research recommendations provided in this review will form the basis for all photochemical reactions initiated by VUV radiation with water as the backing agent. 展开更多
关键词 VACUUM-ULTRAVIOLET Reactive free radicals UV dose Advanced reduction processes Direct photolysis
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Effects of silver nanoparticles with different dosing regimens and exposure media on artificial ecosystem 被引量:2
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作者 Jingwen Zeng Piao Xu +9 位作者 Guiqiu Chen Guangming Zeng Anwei Chen Liang Hu Zhenzhen Huang Kai He Zhi Guo Weiwei Liu Jing Wu Jiangbo Shi 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2019年第1期181-192,共12页
Due to the wide use of silver nanoparticles(AgNPs) in various fields, it is crucial to explore the potential negative impacts on the aquatic environment of AgNPs entering into the environment in different ways. In thi... Due to the wide use of silver nanoparticles(AgNPs) in various fields, it is crucial to explore the potential negative impacts on the aquatic environment of AgNPs entering into the environment in different ways. In this study, comparative experiments were conducted to investigate the toxicological impacts of polyvinylpyrrolidone-coated silver nanoparticles(PVP-AgNPs) with two kinds of dosing regimens, continuous and one-time pulsed dosing, in different exposure media(deionized water and XiangJiang River water). There were a number of quite different experimental results(including 100% mortality of zebrafish,decline in the activity of enzymes, and lowest number and length of adventitious roots) in the one-time pulsed dosing regimen at high PVP-AgNP concentration exposure(HOE)compared to the three other treatments. Meanwhile, we determined that the concentration of leached silver ions from PVP-AgNPs was too low to play a role in zebrafish death. Those results showed that HOE led to a range of dramatic ecosystem impacts which were more destructive than those of other treatments. Moreover, compared with the continuous dosing regimen, despite the fact that higher toxicity was observed for HOE, there was little difference in the removal of total silver from the aquatic environment for the different dosing regimens. No obvious differences in ecological impacts were observed between different water columns under low concentration exposure. Overall, this work highlighted the fact that the toxicity of Ag NPs was impacted by different dosing regimens in different exposure media, which may be helpful for assessments of ecological impacts on aquatic environments. 展开更多
关键词 SILVER nanoparticles TOXICITY dosing REGIMEN SILVER ions ZEBRAFISH
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The PLC Control System of Vacuum Resin Shot Dosing Equipment 被引量:1
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作者 ZHU Shao-ying, XU Yu, HE Zheng-wen Xi′an Jiaotong University, Xi′an 710049, P.R.China 《International Journal of Plant Engineering and Management》 2003年第3期149-153,共5页
The principle and working process of Vacuum Resin Shot Dosing Equipment(VRSDE) are analyzed and the characteristics of IP1612-220PLC (Programmable Logical Controller) areintroduced briefly at first. Then the authors d... The principle and working process of Vacuum Resin Shot Dosing Equipment(VRSDE) are analyzed and the characteristics of IP1612-220PLC (Programmable Logical Controller) areintroduced briefly at first. Then the authors discuss the flow of program, the assignment of PLCI/O ports, the wiring diagram, and the ladder logic program of the PLC control system of VRSDE indetail. Some application issues of the system are accounted for in addition. Finally, according tothe information acquired from users, the authors draw the conclusion: this system owns a highreliability and a-vailability and greatly improves the automatic degree of VRDE. 展开更多
关键词 vacuum resin shot dosing equipment (VRSDE) PLC control system
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A Fuzzy Mathematics Based Fault Auto-diagnosis System for Vacuum Resin Shot Dosing Equipment
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作者 HE Zheng wen, XU Yu, WU Jun School of Management, Xi’an Jiaotong University, Xi’an 710049, P.R.China 《International Journal of Plant Engineering and Management》 2001年第4期170-178,共9页
On the basis of the analysis of faults and their causes of vacuum resin shot dosing equipment, the fuzzy model of fault diagnosis for the equipment is constructed, and the fuzzy relationship matrix, the symptom fuzzy ... On the basis of the analysis of faults and their causes of vacuum resin shot dosing equipment, the fuzzy model of fault diagnosis for the equipment is constructed, and the fuzzy relationship matrix, the symptom fuzzy vector, the fuzzy compound arithmetic operator, and the diagnosis principle of the model are determined. Then the fault auto-diagnosis system for the equipment is designed , and the functions for real-time monitoring its operation condition and for fault auto diagosis are realized. Finally, the experiments of fault auto-diagnosis are conducted in practical production and the veracity of the system is verified. 展开更多
关键词 fuzzy model fault auto diagnosis system vacuum resin shot dosing equipment
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Bandstructure Engineering by Surface Water Dosing on SrFe_(2)As_(2)
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作者 Y.M.Zhang F.Wu +12 位作者 W.J.Shi Z.A.Xu S.C.Shi G.Y.He C.Chen H.F.Yang L.X.Yang Z.Liu W.Lu Y.Zhang Y.F.Guo Y.L.Chen Z.K.Liu 《Chinese Physics Letters》 2025年第10期238-262,共25页
Fe-based superconductors represent a fascinating class of materials,extensively studied for their complex interplay of superconductivity,magnetism,spin density waves,and nematicity,along with the interactions among th... Fe-based superconductors represent a fascinating class of materials,extensively studied for their complex interplay of superconductivity,magnetism,spin density waves,and nematicity,along with the interactions among these orders.An intriguing yet unexplained phenomenon observed in Fe-based superconductors is the emergence of superconductivity below 25K in the non-superconducting parent compound SrFe_(2)As_(2)following exposure to water at its surface.In this study,we employed in situ angle-resolved photoemission spectroscopy and low-energy electron diffraction to meticulously examine the electronic structure evolution of SrFe_(2)As_(2)upon in situ water dosing.Our findings indicate that water dosing markedly attenuates the spin density wave phase and surface Sr reconstruction while preserving the nematic order in SrFe_(2)As_(2).Furthermore,we detected an enhancement in the spectral weight of bands near the Fermi level.Our observations highlight the critical role of the intricate interplay among various orders induced by water dosing,which effectively modifies the band structure and favors the emergence of superconductivity in SrFe_(2)As_(2). 展开更多
关键词 nematic order emergence superconductivity spin density wave band structure surface water dosing SrFe electronic structure evolution SUPERCONDUCTIVITY
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Regional multi-center randomized trial of three vonoprazanamoxicillin dosing regimens for Helicobacter pylori eradication in Sichuan Province,China
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作者 Chao-Qun Wu Xiu Zhou +19 位作者 Chang-Ping Li Qing-Ling He Zong-Hua Chen Shun-Bin Ding Lei Deng Lin-Lin Chen Kai Jiang Cheng-Kui Dong Lian Hu Guo-Bing Zhu Cheng-Gang Zhang Yan Zhang Li-Li Wu Wei Li Yi-Hong Mao Hua Zhang Xia Ai Yuan-Qing He Yan Ma Shuang-Yan He 《World Journal of Gastroenterology》 2025年第47期128-139,共12页
BACKGROUND Helicobacter pylori(H.pylori)infection is highly prevalent worldwide,and rising antibiotic resistance has reduced the efficacy of standard therapy,underscoring the need for simplified and better-tolerated r... BACKGROUND Helicobacter pylori(H.pylori)infection is highly prevalent worldwide,and rising antibiotic resistance has reduced the efficacy of standard therapy,underscoring the need for simplified and better-tolerated regimens.AIM To evaluate the efficacy,safety,and optimal dosing of vonoprazan(VPZ)-amoxicillin(AMO)dual therapy in a non-inferiority randomized trial for H.pylori eradication.METHODS In this multi-center,randomized trial conducted at 17 hospitals in Sichuan Province,China,1717 adults with confirmed infection were assigned(1:1:1)to 14-day regimens:(1)VPZ 20 mg BID+AMO 0.5 g QID;(2)0.75 g QID;or(3)1.0 g TID.The primary endpoint was the eradication rate based on intention-to-treat(ITT)and per-protocol(PP)analyses;secondary endpoints included adverse events(AEs)and treatment compliance.RESULTS Eradication rates were consistently high(92.35%-97.43%).In the 0.5 g QID group,ITT and PP eradication rates were 93.3%(95%CI:91.2-95.1)and 97.4%(95%CI:95.7-98.5),respectively,with no significant differences among groups(P>0.05).Compliance ranged from 98.1%to 98.3%,and AEs were infrequent(5.2%-7.5%),predominantly mild gastrointestinal symptoms,which occurred least often in the 0.5 g QID group.CONCLUSION VPZ-AMO dual therapy achieved excellent eradication,safety,and patient compliance.All regimens were similarly effective,whereas the 0.5 g QID dosing strategy offered the most favorable balance of efficacy and tolerability,supporting its use as a first-line option in high-prevalence settings. 展开更多
关键词 Vonoprazan AMOXICILLIN Helicobacter pylori Potassium-competitive acid blockers Dose
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Biogeochemical behavior of ^(210)Po in the aquatic ecosystem of the North Crimean Canal and adjacent irrigated soils
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作者 A.A.Korotkov N.Yu.Mirzoeva +1 位作者 O.N.Miroshnichenko I.N.Moseichenko 《Acta Geochimica》 2025年第2期314-324,共11页
The main objectives of this study were to investigate the distribution features of the ^(210)Po in abiotic(water and bottom sediments)and biotic(zooplankton,mollusks,fish)components of the North Crimean Canal(NCC)aqua... The main objectives of this study were to investigate the distribution features of the ^(210)Po in abiotic(water and bottom sediments)and biotic(zooplankton,mollusks,fish)components of the North Crimean Canal(NCC)aquatic ecosystem and adjacent irrigated soils as well as assessment of the doses received by water organisms from α-radiation of absorbed ^(210)Po.The samples were processed using standard radiochemical methods accepted in international practice.The activity of ^(210)Po in the samples was measured using the alpha-spectrometric OCTETE Plus complex(ORTEC-AMETEK,USA).The measurement error did not exceed 20%.Activity concentration of ^(210)Po in the studied objects decreased in the following rank:suspended matter(73.6 Bq/kg d.w.)>soils(32.5 Bq/kg d.w.)≈bottom sediments(32.1 Bq/kg d.w.)>mollusks(23.4 Bq/kg w.w.)>fish(6.4 Bq/kg w.w.).The ^(210)Po distribution coefficient(K_(d))values in water between suspended matter and its dissolved parts varied within the 1.4×10^(4)-1.4×10^(5) L/kg range.The concentration factors(CF)of ^(210)Po for hydrobionts of the NCC were in the range 10^(3)-10^(4) L/kg.The calculated absorbed radiation doses from ^(210)Po alpha radiation for the hydrobionts of the North Crimean Canal were significantly below the recommended dose limits. 展开更多
关键词 ^(210)Po North Crimean Canal ecosystem Water HYDROBIONTS Bottom sediments Irrigated soils Equivalent dose
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Applications of photon-counting CT in oncologic imaging:A systematic review
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作者 Arosh S Perera Molligoda Arachchige Anna Dashiell +7 位作者 Anton Shiraan Jesuraj Antonia Immacolata D’Urso Benedetta Fiore Martina Cattaneo Emilia Pierzynska Sandra Szydelko Francesca Romana Centini Yash Verma 《World Journal of Radiology》 2025年第8期74-83,共10页
BACKGROUND Photon-counting detector(PCD)CT represents a transformative advancement in radiological imaging,offering superior spatial resolution,enhanced contrast-tonoise ratio,and reduced radiation dose compared with ... BACKGROUND Photon-counting detector(PCD)CT represents a transformative advancement in radiological imaging,offering superior spatial resolution,enhanced contrast-tonoise ratio,and reduced radiation dose compared with the conventional energyintegrating detector CT.AIM To evaluate PCD CT in oncologic imaging,focusing on its role in tumor detection,staging,and treatment response assessment.METHODS We performed a systematic PubMed search from January 1,2017 to December 31,2024,using the keywords“photon-counting CT”,“cancer”,and“tumor”to identify studies on its use in oncologic imaging.We included experimental studies on humans or human phantoms and excluded reviews,commentaries,editorials,non-English,animal,and non-experimental studies.Study selection followed Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines.Out of 175 initial studies,39 met the inclusion criteria after screening and full-text review.Data extraction focused on study type,country of origin,and oncologic applications of photon-counting CT.No formal risk of bias assessment was performed,and the review was not registered in PROSPERO as it did not include a meta-analysis.RESULTS Key findings highlighted the advantages of PCD CT in imaging renal masses,adrenal adenomas,ovarian cancer,breast cancer,prostate cancer,pancreatic tumors,hepatocellular carcinoma,metastases,multiple myeloma,and lung cancer.Additionally,PCD CT has demonstrated improved lesion characterization and enhanced diagnostic accuracy in oncology.Despite its promising capabilities challenges related to data processing,storage,and accessibility remain.CONCLUSION As PCD CT technology evolves,its integration into routine oncologic imaging has the potential to significantly enhance cancer diagnosis and patient management. 展开更多
关键词 Photon-counting detector CT Oncologic imaging Cancer detection Tumor characterization Spectral imaging Radiology Computed tomography Photon-counting detector CT applications Diagnostic imaging Radiation dose reduction
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Health Phys.Abstracts,Volume 129,Number 5
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《辐射防护》 北大核心 2026年第1期91-96,共6页
Discrete Bayesian Dose-response Analysis under Dose Uncertainty.Eduard Hofer1(1.3 Constance Road,Claremont,Cape Town 7708,South Africa.)Abstract:Establishing a relationship between disease and dose requires each indiv... Discrete Bayesian Dose-response Analysis under Dose Uncertainty.Eduard Hofer1(1.3 Constance Road,Claremont,Cape Town 7708,South Africa.)Abstract:Establishing a relationship between disease and dose requires each individual in the population under investigation to be known by disease status and by the value of the dose received. 展开更多
关键词 Bayesian analysis dose response relationship disease dose dose uncertainty
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Health Phys.Abstracts,Volume 129,Number 4
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《辐射防护》 北大核心 2026年第1期87-91,共5页
Analysis Method of ^(131)I Activity in Carbon Cartridge and Internal Dose Assessment for Nuclear Medicine Workers.Shuo Wang1,Fei Tuo1,Jian-feng Zhang1,Xiao-liang Li1,Bao-lu Yang1,Qiang Zhou1,Ze-shu Li1,Shu-ying Kong1,... Analysis Method of ^(131)I Activity in Carbon Cartridge and Internal Dose Assessment for Nuclear Medicine Workers.Shuo Wang1,Fei Tuo1,Jian-feng Zhang1,Xiao-liang Li1,Bao-lu Yang1,Qiang Zhou1,Ze-shu Li1,Shu-ying Kong1,and Wei-hao Qin1(1.National Institute for Radiological Protection,Chinese Center for Disease Control and Prevention,Beijing,100088,China.) 展开更多
关键词 nuclear medicine workers health physics carbon cartridge internal dose assessment analysis method I activity
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Muscle mass correlates with rocuronium distribution volume and guides dose optimization in obese colorectal cancer patients
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作者 Zhan-Wen Li Zhe Liu Sheng-Qun Liu 《World Journal of Gastrointestinal Oncology》 2026年第1期176-189,共14页
BACKGROUND Perioperative anesthesia management of obese patients presents significant challenges as traditional total body weight-based dosing fails to achieve optimal anesthetic effects due to altered pharmacokinetic... BACKGROUND Perioperative anesthesia management of obese patients presents significant challenges as traditional total body weight-based dosing fails to achieve optimal anesthetic effects due to altered pharmacokinetic characteristics including abnormal drug distribution and clearance.Rocuronium exhibits markedly different distribution patterns in obese patients,with conventional weight correction methods inadequately addressing individual muscle mass variations that critically influence drug distribution.AIM To investigate the quantitative relationship between skeletal muscle index(SMI)and rocuronium distribution volume in obese colorectal cancer patients,establish a population pharmacokinetic model,and develop individualized dosing strategies based on muscle mass.METHODS A retrospective cohort study was conducted,including 100 obese patients(body mass index≥30 kg/m^(2))who underwent elective radical colorectal cancer surgery at our hospital from June 2023 to January 2025.Skeletal muscle mass was measured using InBody 260 body composition analyzer and SMI was calculated to assess muscle mass,with male SMI<7.0 kg/m^(2) and female SMI<5.7 kg/m^(2)as diagnostic criteria for sarcopenia.Plasma rocuronium concentrations were detected by liquid chromatography-tandem mass spectrometry/mass spectrometry,and nonlinear mixed-effect modeling was used to establish population pharmacokinetic modeling.Stepwise regression was used to screen covariates,and dosing regimens were optimized through Monte Carlo simulation.The primary endpoint was targeted plasma concentration achievement rate,and the secondary endpoint was postoperative residual muscle relaxation incidence.RESULTS Among 100 patients,35(35.0%)had sarcopenia and 65(65.0%)did not.Patients in the sarcopenia group were older(64.1±9.8 years vs 54.2±10.9 years,P<0.001)and had significantly lower SMI(6.2±0.8 kg/m^(2)vs 8.4±1.2 kg/m^(2),P<0.001).SMI showed strong positive correlation with rocuronium steady-state distribution volume(r=0.718,P<0.001)and moderate negative correlation with clearance(r=-0.502,P<0.001).A two-compartment population pharmacokinetic model was successfully established,with SMI being the most important covariate affecting central compartment distribution volume(△OFV=-41.2,P<0.001).Model validation showed bootstrap successful convergence rate of 92.3%,and 92.1%of observed values fell within prediction intervals in predicted concentration versus predicted concentration.The SMI-based individualized dosing regimen improved target exposure achievement rate from 82.0%in traditional regimen to 93.5%(P=0.009),and reduced postoperative residual muscle relaxation incidence from 13.0%to 3.5%(P=0.018).The sarcopenia group showed the most significant improvement in achievement rate,from 71.4%to 93.8%(P=0.017).CONCLUSION SMI shows strong correlation with rocuronium distribution volume in obese colorectal cancer patients and is a key factor affecting drug distribution.SMI-based individualized dosing strategies can significantly improve target exposure achievement rate and reduce postoperative residual muscle relaxation incidence,providing scientific evidence for precision anesthesia management in obese patients. 展开更多
关键词 Obesity ROCURONIUM Skeletal muscle index Population pharmacokinetics Individualized dosing Colorectal cancer SARCOPENIA
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Evaluation of polycarbonate films as detection materials for high‑dose electron beam radiation detection
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作者 Ke Wang Xiao‑Dong Wang Xiong‑Hui Fei 《Nuclear Science and Techniques》 2026年第1期141-151,共11页
In this study,the dosimetric characteristics(thickness applicability,preheating time,temperature and humidity dependence,in-batch uniformity,readout reproducibility,dose linearity,self-decay,and electron energy respon... In this study,the dosimetric characteristics(thickness applicability,preheating time,temperature and humidity dependence,in-batch uniformity,readout reproducibility,dose linearity,self-decay,and electron energy response)of engineered polycarbonate films irradiated with an electron beam(0–600 kGy)were investigated using photoluminescence spectroscopy.The results show a linear relationship between photoluminescence intensity and radiation dose when the thickness of the polycarbonate film is 0.3 mm.A higher fluorescence intensity can be obtained by preheating at 60℃ for 180 min before photoluminescence spectrum analysis.As the temperature during spectral testing and the ambient humidity(during and after irradiation)increased,the photoluminescence intensity of the polycarbonate films decreased.The photoluminescence intensity deviation of the polycarbonate films produced within the same batch at 100 kGy is 2.73%.After ten times of repeated excitations and readouts,the coefficients of variation in photoluminescence intensity are less than 8.6%,and the linear correlation coefficient between photoluminescence intensity and irradiation dose is 0.965 in the dose capture range of 20–600 kGy.Within 60 days of irradiation,the photoluminescence intensity of the polycarbonate film decreased to 60%of the initial value.The response of the 0.3 mm polycarbonate films to electron beams with energies exceeding 3.5 MeV does not differ significantly.This comprehensive analysis indicates the potential of polycarbonate films as a high-radiation dose detection material. 展开更多
关键词 Electron beam irradiation POLYCARBONATE Dose detection Radiophotoluminescence Dosimetric characteristics
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Flux-based assessment of ozone visible foliar injury in Southern Alps
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作者 Elena Marra Alessandra De Marco +8 位作者 Andrea Ebone Anna Maria Ferrara Fabio Giannetti Francesco Tagliaferro Pierre Sicard Andrei Popa Ionel Popa Elena Paoletti Yasutomo Hoshika 《Journal of Forestry Research》 2026年第2期31-43,共13页
Tropospheric ozone(O_(3))is a harmful air pollutant negatively impacting forest health,causing O_(3)-specific visible foliar injury(O_(3)VFI).Ozone monitoring in forests has usually implemented by passive samplers,alt... Tropospheric ozone(O_(3))is a harmful air pollutant negatively impacting forest health,causing O_(3)-specific visible foliar injury(O_(3)VFI).Ozone monitoring in forests has usually implemented by passive samplers,although they cannot detect the diurnal peak when a significant part of stomatal O_(3)uptake occurs.This results into uncertainties for the calculation of stomatal O_(3)uptake.This study compares the stomatal-flux-based POD1(phytotoxic ozone dose above a threshold of 1 nmol m^(-2)s^(-1))for forest trees/shrubs estimated from data collected by either passive samplers or active O_(3)monitors to evaluate O_(3)damage to plants in terms of O_(3)VFI in the Southern Alps.The study was conducted over two years(2018-2019)in a mountainous Alpine area(Valle Stura,Italy).An integrative monitoring station for active O_(3)monitoring,as well as passive O_(3)monitors,were installed in an open field area(OFD).The O_(3)VFI was investigated in woody species in the light exposed sampling Site(LESS—Betula pendula,Fagus sylvatica,Larix decidua,Populus tremula,Salix caprea,Rubus sp.and Vaccinium myrtillus)in late summer according to the international co-operative programme on assessment and monitoring of air pollution effects on forests(ICP Forests)manual.The results confirmed that Fagus sylvatica and Rubus sp.are O_(3)-sensitive species showing relatively high POD1(>20 mmol m-2),while Larix decidua is O_(3)-tolerant.We derived flux-based critical levels(CL)corresponding to the presence of O_(3)VFI(5,25,and 50%of symptomatic plants along the LESS)from flux-effect relationships for forest protection against O_(3)VFI.The results support the hypothesis that passive samplers cannot detect episodic high stomatal O₃fluxes(>1 nmol m^(-2)s^(-1)).According to the active monitoring,the CL for O_(3)VFI occurrence was estimated to be 17.1 mmol m-2 POD1 for 25%presence and 34.3 mmol m-2 POD1 for 50%presence of symptomatic plants,while passive samplers underestimated POD1 values for CL calculations by 17%on average,with underestimation increasing at higher CL thresholds.The findings demonstrate that active monitoring refines CLs towards a proper quantitative assessment of O_(3)impact,particularly in capturing peak flux events that are crucial for evaluating plant damage and emphasizes the importance of active O₃monitoring for reliable forest health assessments. 展开更多
关键词 Stomatal conductance model Leaf symptoms FOREST Phytotoxic ozone dose
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Hardened design and practical effect of 60 V trench MOSFET resistant to irradiation
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作者 De-Xin Chen Ying Wang +3 位作者 Huo-Lin Huang Yan-Xing Song Meng-Tian Bao Fei Cao 《Nuclear Science and Techniques》 2026年第4期104-114,共11页
This study focuses on a 60 V trench MOSFET device designed for operation in space radiation environments.By increasing the bulk region concentration and placing the etched gate trench after the P+implantation process,... This study focuses on a 60 V trench MOSFET device designed for operation in space radiation environments.By increasing the bulk region concentration and placing the etched gate trench after the P+implantation process,we successfully reduced the threshold voltage shift from 6.5 to 2.2 V under a total dose of 400 krad(Si)^(60)Co,allowing the device to operate normally.Structurally,by embedding the source metal in the active and terminal regions,the device demonstrated current degradation without experiencing single-event burnout when subjected to a drain voltage of 60 V and a linear energy transfer value of 75.4 MeV·cm^(2)∕mg from tantalum-ion incidence.TCAD simulations verified that the embedded source metal effectively suppressed parasitic transistor conduction and eliminated the base-region expansion effect,thereby lowering the maximum temperature from 8000 to 1400 K.The irradiation effects of the embedded source metal in the terminal region were also investigated,which can improve the reverse recovery and ensure that the terminal metal does not melt prematurely,thereby significantly enhancing the radiation hardness of the device. 展开更多
关键词 Trench MOSFET Single-event burnout(SEB) Total ionizing dose(TID) Hardened structure Lattice temperature
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Comparison of split-dosing vs non-split(morning) dosing regimen for assessment of quality of bowel preparation for colonoscopy 被引量:11
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作者 Hardik Shah Devendra Desai +4 位作者 Hrishikesh Samant Sandeep Davavala Anand Joshi Tarun Gupta Philip Abraham 《World Journal of Gastrointestinal Endoscopy》 CAS 2014年第12期606-611,共6页
AIM: To compare(using the Ottawa Bowel Preparation Scale) the efficacy of split-dose vs morning administration of polyethylene glycol solution for colon cleansing in patients undergoing colonoscopy, and to assess the ... AIM: To compare(using the Ottawa Bowel Preparation Scale) the efficacy of split-dose vs morning administration of polyethylene glycol solution for colon cleansing in patients undergoing colonoscopy, and to assess the optimal preparation-to-colonoscopy interval.METHODS: Single-centre, prospective, randomized, investigator-blind stud in an academic tertiarycare centre. Two hundred patients requiring elective colonoscopy were assigned to receive one of the two preparation regimens(split vs morning) prior to colonoscopy. Main outcome measurements were bowel preparation quality and patient tolerability.RESULTS: Split-dose regimen resulted in better bowel preparation compared to morning regimen [Ottawascore mean 5.52(SD 1.23) vs 6.02(1.34); P = 0.017]. On subgroup analysis, for afternoon procedures, both the preparations were equally effective(P = 0.756). There was no difference in tolerability and compliance between the two regimens.CONCLUSION: Overall, previous evening- same morning split-dosing regimen results in better bowel cleansing for colonoscopy compared to morning preparation. For afternoon procedures, both schedules are equally effective; morning preparation may be more convenient to the patient. 展开更多
关键词 BOWEL PREPARATION COLONOSCOPY MORNING PREPARATION SPLIT dose PREPARATION PREPARATION to COLONOSCOPY interval
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SRDAAR-QNPP:a computer code system for the real-time dose assessment of an accident release for Qinshan Nuclear Power Plant 被引量:5
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作者 Hu Erbang Wang Han(China Institute for Radiation Protection, Taiyuan 030006, China) 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 1994年第3期296-309,共14页
The paper presents a computer code system 'SRDAAR- QNPP' for the real-time dose as-sessment of an accident release for Qinshan Nuclear Power Plant. It includes three parts:thereal-time data acquisition system,... The paper presents a computer code system 'SRDAAR- QNPP' for the real-time dose as-sessment of an accident release for Qinshan Nuclear Power Plant. It includes three parts:thereal-time data acquisition system, assessment computer. and the assessment operating code system. InSRDAAR-QNPP, the wind field of the surface and the lower levels are determined hourly by using amass consistent three-dimension diasnosis model with the topographic following coordinate system.A Lagrangin Puff model under changing meteorological condition is adopted for atmosphericdispersion, the correction for dry and wet depositions. physical decay and partial plume penetrationof the top inversion and the deviation of plume axis caused by complex terrain have been taken in-to account. The calculation domain areas include three square grid areas with the sideline 10 km, 40krn and 160 km and a grid interval 0.5 km, 2.0 km, 8.0 km respectively. Three exposure pathwaysare taken into account:the external exposure from immersion cloud and passing puff, the internalexposure from inhalation and the external exposure from contaminated ground. This system is ableto provide the results of concentration and dose distributions within 10 minutes after the data havebeen inputed. 展开更多
关键词 REAL-TIME dose assessment computer code system nuclear power plant accident.
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Town-scale microbial sewer community and H2S emissions response to common chemical and biological dosing treatments 被引量:2
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作者 Elizabeth R.Mathews Jennifer L.Wood +3 位作者 Dean Phillips Nathan Billington Dean Barnett Ashley E.Franks 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2020年第1期133-148,共16页
Controlling hydrogen sulfide(H2S)odors and emissions using a single,effective treatment across a town-scale sewer network is a challenge faced by many water utilities.Implementation of a sewer diversion provided the o... Controlling hydrogen sulfide(H2S)odors and emissions using a single,effective treatment across a town-scale sewer network is a challenge faced by many water utilities.Implementation of a sewer diversion provided the opportunity to compare the effectiveness of magnesium hydroxide(Mg(OH)2)and two biological dosing compounds(Bioproducts A and B),with different modes of action(MOA),in a field-test across a large sewer network.Mg(OH)2 increases sewer p H allowing suppression of H2S release into the sewer environment while Bioproduct A acts to disrupt microbial communication through quorum sensing(QS),reducing biofilm integrity.Bioproduct B reduces H2S odors by scouring the sewer of fats,oils and grease(FOGs),which provide adhesion points for the microbial biofilm.Results revealed that only Mg(OH)2 altered the microbial community structure and reduced H2S emissions in a live sewer system,whilst Bioproducts A and B did not reduce H2S emissions or have an observable effect on the composition of the microbial community at the dosed site.Study results recommend in situ testing of dosing treatments before implementation across an operational system. 展开更多
关键词 Microbially induced concrete corrosion Biological dosing treatments Magnesium hydroxide Hydrogen sulfide Sulfate-reducing bacteria Microbial ecology
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Comparison of the efficacy and safety of once-daily dosing and on-demand use of udenafil for type 2 diabetic patients with erectile dysfunction 被引量:2
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作者 Soon Hyun Park Sung Woo Park +6 位作者 Bong Yun Cha Ie Byung Park Kyung Wan Min Yeon Ah Sung Tae Hwa Kim Jae Min Lee Kang Seo Park 《Asian Journal of Andrology》 SCIE CAS CSCD 2015年第1期143-148,I0011,I0012,共8页
We compared the efficacy and safety between once-daily dosing and on-demand use of udenafil for type 2 diabetic patients with erectile dysfunction (ED). A multi-center, randomized, open-label, parallel-group, 12-wee... We compared the efficacy and safety between once-daily dosing and on-demand use of udenafil for type 2 diabetic patients with erectile dysfunction (ED). A multi-center, randomized, open-label, parallel-group, 12-week study was conducted. 161 patients who improved with on-demand 200 mg of udenafil according to Sexual Encounter Profile (SEP) diary Question 2 and 3 (Q2 and Q3) were randomized into 200 mg on-demand (n = 80) or 50 mg once-daily (n = 81) dosing groups for 8 weeks. The dosing period was followed by a 4-week treatment-free period. The primary efficacy endpoint was the change of the International Index of Erectile Function (IIEF) erectile function domain (EFD) score. The secondary efficacy endpoints included changes to the SEP diary Q2, Q3, IIEF Q3, Q4, other domains of IIEF, Global Assessment Question, and shift to the normal rate (EFD 〉 26). Vascular endothelial markers were also assessed. The IIEF-EFD score of both groups improved after 8 weeks of treatment (P 〈 0.0001). There was no statistically significant difference between two groups. Improvement was not maintained after the treatment-free follow-up period. Similar results were observed in the secondary efficacy endpoints. There was also no significant difference in vascular endothelial markers. Daily udenafil was well-tolerated, and there was no significant difference in the adverse drug reactions and adverse events between the two groups. Flushing and headache were the most frequent adverse events. Both regimens improved ED in diabetic patients and were well-tolerated. Further studies are needed to assess the effect of daily udenafil treatment in diabetic patients. 展开更多
关键词 erectile dysfunction International Index of Erectile Function once-daily dosing ptiosphodiesterase type 5 inhibitor type 2 diabetes mellitus UDENAFIL
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Optimal dosing time of acid algaecide for restraining algal growth 被引量:3
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作者 Cui-chao PANG Xin-jian FAN +1 位作者 Jie ZHOU Shi-qiang WU 《Water Science and Engineering》 EI CAS CSCD 2013年第4期402-408,共7页
Restraining algal growth by algaecide has been studied by many researchers, but the dosing time has not yet been studied. In this study, we examined the appropriate dosing time of algaecide through a series of experim... Restraining algal growth by algaecide has been studied by many researchers, but the dosing time has not yet been studied. In this study, we examined the appropriate dosing time of algaecide through a series of experiments. In the experiments, the pH value of water is significantly affected by Microcystis aeruginosa, and the variation of the pH value is in favor of the growth of the alga. Therefore, using acid algaecide in the period with maximum pH values, i.e., the stable phase, would change the acidity-alkalinity of the water significantly, and would negatively affect algal growth. Acid algaecide does not eliminate the alga effectively if the acid algaecide is dosed in the logarithmic growth phase. Using acid algaecide in the decline phase after algal bloom not only is unfavorable for eliminating the alga, but also prolongs the decline phase, and even brings about next larger algal bloom. 展开更多
关键词 Microcystis aeruginosa algal bloom acid algaecide dosing time
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