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Chlorfenapyr poisoning:mechanisms,clinical presentations,and treatment strategies
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作者 Ji Cheng Yulu Chen +4 位作者 Weidong Wang Xueqi Zhu Zhenluo Jiang Peng Liu Liwen Du 《World Journal of Emergency Medicine》 SCIE CAS CSCD 2024年第3期214-219,共6页
BACKGROUND:Chlorfenapyr is used to kill insects that are resistant to organophosphorus insecticides.Chlorfenapyr poisoning has a high mortality rate and is difficult to treat.This article aims to review the mechanisms... BACKGROUND:Chlorfenapyr is used to kill insects that are resistant to organophosphorus insecticides.Chlorfenapyr poisoning has a high mortality rate and is difficult to treat.This article aims to review the mechanisms,clinical presentations,and treatment strategies for chlorfenapyr poisoning.DATA RESOURCES:We conducted a review of the literature using PubMed,Web of Science,and SpringerLink from their beginnings to the end of October 2023.The inclusion criteria were systematic reviews,clinical guidelines,retrospective studies,and case reports on chlorfenapyr poisoning that focused on its mechanisms,clinical presentations,and treatment strategies.The references in the included studies were also examined to identify additional sources.RESULTS:We included 57 studies in this review.Chlorfenapyr can be degraded into tralopyril,which is more toxic and reduces energy production by inhibiting the conversion of adenosine diphosphate to adenosine triphosphate.High fever and altered mental status are characteristic clinical presentations of chlorfenapyr poisoning.Once it occurs,respiratory failure occurs immediately,ultimately leading to cardiac arrest and death.Chlorfenapyr poisoning is diflcult to treat,and there is no specific antidote.CONCLUSION:Chlorfenapyr is a new pyrrole pesticide.Although it has been identified as a moderately toxic pesticide by the World Health Organization(WHO),the mortality rate of poisoned patients is extremely high.There is no specific antidote for chlorfenapyr poisoning.Therefore,based on the literature review,future efforts to explore rapid and effective detoxification methods,reconstitute intracellular oxidative phosphorylation couplings,identify early biomarkers of chlorfenapyr poisoning,and block the conversion of chlorfenapyr to tralopyril may be helpful for emergency physicians in the diagnosis and treatment of this disease. 展开更多
关键词 Chlorfenapyr poisoning MECHANISM Clinical presentation TREATMENT
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The value of toxicological analysis in acute poisoning patients with uncertain exposure histories:a retrospective and descriptive study from an institute of poisoning
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作者 Qifang Shi Gen Ba +3 位作者 Zhenyu Xia Zhengsheng Mao Hao Sun Jinsong Zhang 《World Journal of Emergency Medicine》 SCIE CAS CSCD 2024年第2期98-104,共7页
BACKGROUND:In clinical practice,some patients might not be able or unwilling to provide a thorough history of medication and poison exposure.The aim of this study was to use toxicological analysis to examine the clini... BACKGROUND:In clinical practice,some patients might not be able or unwilling to provide a thorough history of medication and poison exposure.The aim of this study was to use toxicological analysis to examine the clinical characteristics of patients with acute poisoning whose exposure history was uncertain from a toxicological analysis perspective.METHODS:This was a retrospective and descriptive study from an institute of poisoning.Patient registration information and test reports spanning the period from April 1,2020 to March 31,2022,were obtained.Patients with uncertain exposure histories and who underwent toxicological analysis were included.Clinical manifestations and categories of toxics were analyzed.RESULTS:Among the 195 patients with positive toxicological analysis results,the main causes of uncertain exposure history was disturbance of consciousness(62.6%),unawareness(23.6%)and unwillingness or lack of cooperation(13.8%).The predominant clinical manifestations were disturbed consciousness(62.6%),followed by vomiting and nausea(14.4%)and liver function abnormalities(8.7%).A comparison of clinical manifestations between patients with positive and negative(n=99)toxicological analyses results revealed significantly different proportions of disturbances in consciousness(63%vs.21%),dizziness(1.5%vs.5.1%),multi-organ failure(1.5%vs.7.1%),and local pain(0 vs 4%).The main categories of substances involved were psychiatric medications(23.1%),sedatives(20.5%),insecticides(13.8%),and herbicides(12.8%).CONCLUSION:The clinical manifestations of acute poisoning in patients with an uncertain exposure history are diverse and nonspecific,and toxicological analysis plays a pivotal role in the diagnosis and differential diagnosis of such patients. 展开更多
关键词 Acute poisoning Toxic exposure Toxicological analysis Clinical manifestation
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The Role of Abdominal CT in the Assessment of the Effectiveness of Gastric Lavage after Pesticide Poisoning
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作者 Minghui Gong Zhengdong Wan 《Journal of Biosciences and Medicines》 2024年第5期293-299,共7页
Pesticide poisoning is one of the most common diseases in the emergency department, characterized by rapid changes in condition, a high misdiagnosis rate, and a poor prognosis. Measures for early removal of poisons ar... Pesticide poisoning is one of the most common diseases in the emergency department, characterized by rapid changes in condition, a high misdiagnosis rate, and a poor prognosis. Measures for early removal of poisons are crucial, and gastric lavage is one of the important measures. Regarding the post-gastric lavage effect, abdominal CT scanning has an important application value in the assessment of the gastric lavage effect after pesticide poisoning. 展开更多
关键词 Abdominal CT Gastric Lavage Pesticide poisoning ASSESSMENT
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Evaluating the Efficacy of Latent Variables in Mitigating Data Poisoning Attacks in the Context of Bayesian Networks:An Empirical Study
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作者 Shahad Alzahrani Hatim Alsuwat Emad Alsuwat 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第5期1635-1654,共20页
Bayesian networks are a powerful class of graphical decision models used to represent causal relationships among variables.However,the reliability and integrity of learned Bayesian network models are highly dependent ... Bayesian networks are a powerful class of graphical decision models used to represent causal relationships among variables.However,the reliability and integrity of learned Bayesian network models are highly dependent on the quality of incoming data streams.One of the primary challenges with Bayesian networks is their vulnerability to adversarial data poisoning attacks,wherein malicious data is injected into the training dataset to negatively influence the Bayesian network models and impair their performance.In this research paper,we propose an efficient framework for detecting data poisoning attacks against Bayesian network structure learning algorithms.Our framework utilizes latent variables to quantify the amount of belief between every two nodes in each causal model over time.We use our innovative methodology to tackle an important issue with data poisoning assaults in the context of Bayesian networks.With regard to four different forms of data poisoning attacks,we specifically aim to strengthen the security and dependability of Bayesian network structure learning techniques,such as the PC algorithm.By doing this,we explore the complexity of this area and offer workablemethods for identifying and reducing these sneaky dangers.Additionally,our research investigates one particular use case,the“Visit to Asia Network.”The practical consequences of using uncertainty as a way to spot cases of data poisoning are explored in this inquiry,which is of utmost relevance.Our results demonstrate the promising efficacy of latent variables in detecting and mitigating the threat of data poisoning attacks.Additionally,our proposed latent-based framework proves to be sensitive in detecting malicious data poisoning attacks in the context of stream data. 展开更多
关键词 Bayesian networks data poisoning attacks latent variables structure learning algorithms adversarial attacks
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Severe aconite poisoning successfully treated with veno-arterial extracorporeal membrane oxygenation:A case report
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作者 Saeko Kohara Yoshito Kamijo +6 位作者 Ryoko Kyan Ichiro Okada Eiju Hasegawa Soichiro Yamada Koichi Imai Asuka Kaizaki-Mitsumoto Satoshi Numazawa 《World Journal of Clinical Cases》 SCIE 2024年第2期399-404,共6页
BACKGROUND Most species of aconite contain highly toxic aconitines,the oral ingestion of which can be fatal,primarily because they cause ventricular arrhythmias.We describe a case of severe aconite poisoning that was ... BACKGROUND Most species of aconite contain highly toxic aconitines,the oral ingestion of which can be fatal,primarily because they cause ventricular arrhythmias.We describe a case of severe aconite poisoning that was successfully treated through venoarterial extracorporeal membrane oxygenation(VA-ECMO)and in which detailed toxicological analyses of the aconite roots and biological samples were performed using liquid chromatography-tandem mass spectrometry(LC-MS/MS).CASE SUMMARY A 23-year-old male presented to the emergency room with circulatory collapse and ventricular arrhythmia after ingesting approximately half of a root labeled,“Aconitum japonicum Thunb”.Two hours after arrival,VA-ECMO was initiated as circulatory collapse became refractory to antiarrhythmics and vasopressors.Nine hours after arrival,an electrocardiogram revealed a return to sinus rhythm.The patient was weaned off VA-ECMO and the ventilator on hospital days 3 and 5,respectively.On hospital day 15,he was transferred to a psychiatric hospital.The other half of the root and his biological samples were toxicologically analyzed using LC-MS/MS,revealing 244.3 mg/kg of aconitine and 24.7 mg/kg of mesaconitine in the root.Serum on admission contained 1.50 ng/mL of aconitine.Beyond hospital day 2,neither were detected.Urine on admission showed 149.09 ng/mL of aconitine and 3.59 ng/mL of mesaconitine,but these rapidly decreased after hospital day 3.CONCLUSION The key to saving the life of a patient with severe aconite poisoning is to introduce VA-ECMO as soon as possible. 展开更多
关键词 Aconite poisoning Fatal arrhythmia Veno-arterial extracorporeal membrane oxygenation ACONITINE MESACONITINE Case report
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Paradoxical systemic toxicity by inhaled paraquat poisoning: A case report
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作者 Tulika Garg Jaspreet Kaur Yuvraj Singh Cheema 《Journal of Acute Disease》 2024年第1期40-42,I0001-I0005,共8页
Rationale:Multi-organ failure is a symptom of paraquat poisoning,resulting in high mortality and morbidity rates.Though paraquat is widely available,poisoning through inhalation is rare.Patient’s Concern:A 37-year-ol... Rationale:Multi-organ failure is a symptom of paraquat poisoning,resulting in high mortality and morbidity rates.Though paraquat is widely available,poisoning through inhalation is rare.Patient’s Concern:A 37-year-old male reported to the emergency department with complaints of vomiting after an alleged history of inhalation of paraquat while at work.Diagnosis:Paraquat poisoning.Interventions:Supportive management along with multiple sessions of hemodialysis.Outcomes:Renal complications caused by paraquat were improved after multiple sessions of hemodialysis.However,the patient developed respiratory complications and later due to persistent hypoxemia and non-responsive to supportive therapy,he succumbed to his illness.Lessons:Acute kidney injury is a complication of paraquat poisoning.However,kidney involvement with the inhalational mode is rare.It is caused by reduction and oxidation cycles,as well as the formation of reactive oxygen species,necessitating hemodialysis as the treatment.Without a clear history,a specific clinical trait,or a diagnostic test,diagnosis can be difficult.Our case thus highlights the inhaled paraquat poisoning,presenting with acute kidney injury with late respiratory impairment as a consequence. 展开更多
关键词 Paraquat poisoning PESTICIDE Acute kidney injury Respiratory insufficiency HEMODIALYSIS
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Multiorgan dysfunction syndrome due to high-dose cantharidin poisoning:A case report
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作者 Wan-Ling Xu Wen-Jing Tang +4 位作者 Wei-Ying Yang Li-Chao Sun Ze-Qun Zhang Wei Li Xiu-Xian Zang 《World Journal of Clinical Cases》 SCIE 2024年第12期2074-2078,共5页
BACKGROUND This report delves into the diagnostic and therapeutic journey undertaken by a patient with high-dose cantharidin poisoning and multiorgan dysfunction syndrome(MODS).Particular emphasis is placed on the com... BACKGROUND This report delves into the diagnostic and therapeutic journey undertaken by a patient with high-dose cantharidin poisoning and multiorgan dysfunction syndrome(MODS).Particular emphasis is placed on the comprehensive elucidation of the clinical manifestations of high-dose cantharidin poisoning,the intricate path to diagnosis,and the exploration of potential underlying mechanisms.CASE SUMMARY A patient taking 10 g of cantharidin powder orally subsequently developed MODS.The patient was treated with supportive care,fluid hydration and antibiotics,and hemoperfusion and hemofiltration therapy for 24 h and successfully recovered 8 d after hospital admission.Cantharidin poisoning can cause lifethreatening MODS and is rare clinically.This case underscores the challenge in diagnosis and highlights the need for early clinical differentiation to facilitate accurate assessment and prompt intervention.CONCLUSION This article has reported and analyzed the clinical data,diagnosis,treatment,and prognosis of a case of high-dose cantharidin poisoning resulting in MODS and reviewed the relevant literature to improve the clinical understanding of this rare condition. 展开更多
关键词 CANTHARIDIN poisoning Multiorgan dysfunction syndrome Clinical treatment and management Case report
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Clinical Case Report of Acute Heart Injury and Acute Rhabdomyolysis Due to Cyanide Poisoning
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作者 Nguyen Dang Duc Nguyen Phuong Sinh Lam Nguyen Hong Anh 《Open Journal of Emergency Medicine》 2024年第2期29-32,共4页
Cyanide poisoning is one of the most dangerous poisonings, and it can be absorbed into the body through the mouth, inhalation and through the skin. A 32-year-old female patient was admitted to our poison control cente... Cyanide poisoning is one of the most dangerous poisonings, and it can be absorbed into the body through the mouth, inhalation and through the skin. A 32-year-old female patient was admitted to our poison control center because of high fever, severe vomiting, and seizures. Physical examination found that the patient was drowsy, had a high fever of 40 degrees Celsius, pulse of 140 beats/minute, and increased tendon and bone reflexes. Exploiting the patient’s information, it was discovered that the patient bought Cyanide to drink with the intention of committing suicide. The patient was quickly treated with gastric lavage and activated charcoal. Echocardiography recorded EF: 35%, reduced movement of the entire myocardium. CK blood test: 4562 U/L. The patient’s condition rapidly deteriorated and the patient was made ECMO, IHD and CVVHDF. After 3 days of treatment, the patient’s condition did not improve, so the family asked for the patient to go home. This article aims to describe the rapidly progressing and severe damage to the heart and muscles of patients with cyanide poisoning. 展开更多
关键词 Cyanide poisoning Acute Heart Injury Acute Rhabdomyolysis
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Influence of element substitutions on poisoning behavior of ZrV_(2)alloy:theoretical and experimental investigations
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作者 Shuang Yang Run-Jie Fang +5 位作者 Guo Yang Li-Jun Lv Xing-Bo Han Wei Liu Xiu-Jie He Peng-Fei Zhu 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2023年第7期253-266,共14页
A ZrV_(2)alloy is typically susceptible to poisoning by impurity gases,which causes a considerable reduction in the hydrogen storage properties of the alloy.In this study,the adsorption characteristics of oxygen on Zr... A ZrV_(2)alloy is typically susceptible to poisoning by impurity gases,which causes a considerable reduction in the hydrogen storage properties of the alloy.In this study,the adsorption characteristics of oxygen on ZrV_(2)surfaces doped with Hf,Ti,and Pd are investigated,and the effect of oxygen on the hydrogen storage performance of the alloy was discussed.Subsequently,the adsorption energy,bond-length change,density of states,and differential charge density of the alloy before and after doping are analyzed using the first-principles method.The theoretical results show that Ti doping has a limited effect on the adsorption of oxygen atoms on the ZrV_(2)surface,whereas Hf doping decreases the adsorption energy of oxygen on the ZrV_(2)surface.Oxygen atoms are more difficult to adsorb at most adsorption sites on Pd-substituting surfaces,which indicates that Pd has the best anti-poisoning properties,followed by Hf.The analysis of the differential charge density and partial density of states show that the electron interaction between the oxygen atom and surface atom of the alloys is weakened,and the total energy is reduced after Hf and Pd doping.Based on theoretical calculations,the hydrogen absorption kinetics of ZrV_(2),Zr_(0.9)Hf_(0.1)V_(2),and Zr(V_(0.9)Pd_(0.1))_(2) alloys are studied in a hydrogen-oxygen mixture of 0.5 vol%O_(2) at 25℃.The experimental results show that the hydrogen storage capacities of ZrV_(2),Zr_(0.9)Hf_(0.1)V_(2),and Zr(V_(0.9)Pd_(0.1))_(2) decrease to 19%,69%,and 80%of their original values,respectively.The order of alloy resistance to 0.5 vol%O_(2) poisoning is Zr(V_(0.9)Pd_(0.1))_(2)>Zr_(0.9)Hf_(0.1)V_(2)>ZrV_(2).Pd retains its original hydrogen absorption performance to a greater extent than undoped surfaces,and it has the strongest resistance to poisoning,which is consistent with previous theoretical calculations. 展开更多
关键词 Hydrogen storage zrV_(2) FIRST-PRINCIPLES poisoning effect
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A Comparison of Hydrothermal Aging, SO2 and Propene Poisoning Effects on NH3-SCR over Cu-ZSM-5 and Cu-SAPO-34 Catalysts
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作者 Kouadio Brou Albert Koffi Konan Martin +1 位作者 Zran Van Eric-Simon Horo Kone 《Journal of Materials Science and Chemical Engineering》 2024年第5期10-28,共19页
This study was aimed to investigate the effects of hydrothermal aging, propene and SO<sub>2</sub> poisoning on the ammonia-selective catalytic reduction (NH<sub>3</sub>-SCR) performance of both... This study was aimed to investigate the effects of hydrothermal aging, propene and SO<sub>2</sub> poisoning on the ammonia-selective catalytic reduction (NH<sub>3</sub>-SCR) performance of both Cu-SAPO-34 and Cu-ZSM-5. The catalytic activities of fresh, aged and poisoned samples were tested in ammonia-selective catalytic reduction (NH<sub>3</sub>-SCR) of NO<sub>x</sub> conditions. The XRD, TG and N<sub>2</sub>-desorption results showed that the structures of the Cu-SAPO-34 and Cu-ZSM-5 remained intact after 750˚C hydrothermally aged, SO<sub>2</sub> and propene poisoned. After hydrothermal aging at 750˚C for 12 h, the NO reduction performance of Cu-ZSM-5 was significantly reduced at lower temperatures, while that of Cu-SAPO-34 was less affected. Moreover, Cu-SAPO-34 catalyst showed high NO conversion with SO<sub>2</sub> or propene compared to Cu-ZSM-5. However, Cu-ZSM-5 showed a larger drop in catalytic activity with SO<sub>2</sub> or propene compared to Cu-SAPO-34 catalyst. The H<sub>2</sub>-TPR results showed that Cu<sup>2 </sup> ions could be reduced to Cu<sup> </sup> and Cu<sup>0</sup> for Cu-ZSM-5, while no significant transformation of copper species was observed for Cu-SAPO-34. Meanwhile, the UV-vis DRS results showed that CuO species were formed in Cu-ZSM-5, while little changes were observed for the Cu-SAPO-34. Cu-SAPO-34 showed high sulfur and hydrocarbon poison resistance compared to Cu-ZSM-5. In summary, Cu-SAPO-34 with small-pore zeolite showed higher hydrothermal stability and better hydrocarbon and sulfur poison resistant than Cu-ZSM-5 with medium-pore. 展开更多
关键词 Hydrothermal Aging Propene and SO2poisoning Ammonia-Selective Catalytic Reduction(NH3-SCR) Cu-SAPO-34 CU-ZSM-5
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不同预时效挤压态Mg−Gd−Y−Zn−Zr合金的再结晶行为和强化机制 被引量:1
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作者 徐健 郑杰 +5 位作者 刘莞尔 黄有旺 闫钊鸣 张治民 王强 薛勇 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2024年第2期480-503,共24页
通过控制预时效时间制备3种不同状态的试样,研究不同预时效状态对挤压态Mg−9.5Gd−4Y−2.2Zn−0.5Zr(质量分数,%)合金的动态再结晶行为(DRX)和性能的影响。结果表明,欠时效挤压(UAE)样品的细晶体积分数为17.4%,而峰时效挤压(PAE)和过时效挤... 通过控制预时效时间制备3种不同状态的试样,研究不同预时效状态对挤压态Mg−9.5Gd−4Y−2.2Zn−0.5Zr(质量分数,%)合金的动态再结晶行为(DRX)和性能的影响。结果表明,欠时效挤压(UAE)样品的细晶体积分数为17.4%,而峰时效挤压(PAE)和过时效挤压(OAE)样品的细晶体积分数分别达到89.7%和50.4%。在晶粒内部和晶界处分布的致密、细小的β颗粒相通过粒子激发形核机制显著提高了形核位点和位错密度。然而,致密针状γ'相抑制位错滑移,延迟DRX形核。PEA和OAE样品中细小晶粒的差异归因于原始颗粒相的数量和尺寸的不同,而其拉伸性能的差异归因于不同的显微组织。由于晶界强化和析出强化机制的贡献更大,PAE样品具有更优异的拉伸性能。 展开更多
关键词 Mg−Gd−Y−Zn−zr合金 预时效处理 再结晶行为 强化机制 粒子刺激形核
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Mg-8Gd-(0,3)Sm-0.5Zr合金的动态再结晶生长动力学 被引量:1
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作者 朱利敏 李全安 +1 位作者 陈晓亚 张清 《材料热处理学报》 CAS CSCD 北大核心 2024年第1期166-174,共9页
利用铸造法制备了Mg-8Gd-(0,3)Sm-0.5Zr合金,并进行了525℃均匀化处理8 h,随后在温度为350~500℃及应变速率为0.002~1 s^(-1)的条件下进行热压缩试验,绘制并分析合金热压缩后的真应力-真应变曲线,构建其动态再结晶生长动力学双参数模型... 利用铸造法制备了Mg-8Gd-(0,3)Sm-0.5Zr合金,并进行了525℃均匀化处理8 h,随后在温度为350~500℃及应变速率为0.002~1 s^(-1)的条件下进行热压缩试验,绘制并分析合金热压缩后的真应力-真应变曲线,构建其动态再结晶生长动力学双参数模型,并分析了合金生长动力学曲线特点及显微组织特征。结果表明:两种合金在热压缩时均发生了动态再结晶,通过双参数模型绘制动态再结晶动力学曲线,发现在高温低应变速率热压缩时,在真应变约0.2时,合金的动态再结晶的体积分数迅速增加至90%以上。对比分析Sm元素添加后的动态再结晶动力学曲线,发现Sm元素促进动态再结晶的进行,尤其在高温低应变速率热压缩时,在变形初期Sm的促进作用更明显。 展开更多
关键词 Mg-8Gd-(0 3)Sm-0.5zr合金 热压缩 动态再结晶
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Co/MOF-808(Zr)复合材料的制备及其对有机磷化合物的降解性能
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作者 黄艳凤 焦克楠 +2 位作者 王晓荣 潘杰 万冬 《天津工业大学学报》 CAS 北大核心 2024年第1期50-55,共6页
为了解决普通单金属MOFs材料几乎不能直接将双(4-硝基苯)磷酸酯(BNPP)直接降解为毒性更低的对氨基苯酚(4-AP)的问题,通过油浴法制备出MOF-808(Zr)后,采用后修饰法将草酸钴负载于MOF-808(Zr)上,制备出Co/MOF-808(Zr)复合材料,并对所制材... 为了解决普通单金属MOFs材料几乎不能直接将双(4-硝基苯)磷酸酯(BNPP)直接降解为毒性更低的对氨基苯酚(4-AP)的问题,通过油浴法制备出MOF-808(Zr)后,采用后修饰法将草酸钴负载于MOF-808(Zr)上,制备出Co/MOF-808(Zr)复合材料,并对所制材料进行XRD和TEM表征。结果表明:MOF-808(Zr)具有高晶体结构稳定性,Co/MOF-808(Zr)的粒径在250 nm左右且分布均匀;Co/MOF-808(Zr)通过级联反应成功将有机磷神经毒剂模拟物BNPP直接降解为毒性更低的4-AP,而非一般的毒性较高的降解产物对硝基苯酚(4-NP)。其最佳级联降解反应条件为:温度45℃,Co/MOF-808(Zr)剂量为2 mg/mL,底物BNPP为0.6 mmol/L,硼氢化钠0.06 mmol/L。实践得出,Co/MOF-808(Zr)在将有机磷化合物直接降解为毒性更低的4-AP方面表现出良好的应用潜力。 展开更多
关键词 Co/MOF-808(zr) 级联反应 水解BNPP 氢化4-NP 有机磷化合物 降解
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Zr对Al-Si-Mg-Mn合金凝固过程、时效组织和性能的影响
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作者 陈安柱 周鹏飞 《矿冶工程》 CAS 北大核心 2024年第3期156-160,165,共6页
通过模拟计算、组织观察以及力学性能测试,研究了不同Zr含量对铸造Al-Si-Mg-Mn合金凝固过程、时效组织及力学性能的影响。结果表明,随着Zr含量增加,合金凝固路径存在显著差异,晶粒由初期树枝晶逐步演变为等轴晶;175℃时效7 h条件下,Zr... 通过模拟计算、组织观察以及力学性能测试,研究了不同Zr含量对铸造Al-Si-Mg-Mn合金凝固过程、时效组织及力学性能的影响。结果表明,随着Zr含量增加,合金凝固路径存在显著差异,晶粒由初期树枝晶逐步演变为等轴晶;175℃时效7 h条件下,Zr的加入显著提高合金硬度。Zr的加入促使析出相在更低时效温度析出,这可能是Zr细化了晶粒从而提高了扩散效率。峰值时效时合金主要析出相为β″相和Q′相。 展开更多
关键词 铝合金 轻量化 析出强化 晶粒细化 zr Al-Si-Mg-Mn 时效 析出相 组织形貌
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退火工艺对Mg-4.0Zn-0.8Zr合金组织与性能的影响
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作者 胡小静 张占领 徐彦伟 《热加工工艺》 北大核心 2024年第14期114-117,共4页
采用金相显微镜、扫描电镜、拉伸试验、浸泡腐蚀试验等手段,研究了不同温度退火对热轧态Mg-4.0Zn-0.8Zr合金组织、力学性能和耐腐蚀性能的影响。结果表明:热轧态Mg-4.0Zn-0.8Zr合金晶粒沿着轧制方向被拉长。320℃退火合金组织仍保持热... 采用金相显微镜、扫描电镜、拉伸试验、浸泡腐蚀试验等手段,研究了不同温度退火对热轧态Mg-4.0Zn-0.8Zr合金组织、力学性能和耐腐蚀性能的影响。结果表明:热轧态Mg-4.0Zn-0.8Zr合金晶粒沿着轧制方向被拉长。320℃退火合金组织仍保持热轧态纤维状形貌,360℃退火合金再结晶完全,晶粒为均匀的等轴晶,退火温度再升高,合金晶粒均匀性变差。随着退火温度的升高,合金的抗拉强度不断下降,伸长率先升高后降低,腐蚀速率先降低后升高。360℃退火的合金伸长率最高,为22.1%,腐蚀速率最低,为0.24 mm/a,其抗拉强度为250.4 MPa。 展开更多
关键词 Mg-4.0Zn-0.8zr合金 退火温度 组织 力学性能 腐蚀速率
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激光熔化沉积Al-Mg-Sc-Zr合金晶粒尺寸预测及成形工艺优化
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作者 刘筱 谢莉 +4 位作者 朱必武 李伟奇 肖罡 李落星 徐从昌 《塑性工程学报》 CAS CSCD 北大核心 2024年第8期92-99,共8页
通过激光熔化沉积试验分析了工艺条件(送粉速度、扫描速度和激光功率)对Al-Mg-Sc-Zr合金晶粒尺寸的影响,构建了晶粒尺寸预测模型,优化了成形工艺参数,给出了工艺参数最佳区间。结果表明,相较于激光功率和扫描速度,送粉速度对晶粒尺寸的... 通过激光熔化沉积试验分析了工艺条件(送粉速度、扫描速度和激光功率)对Al-Mg-Sc-Zr合金晶粒尺寸的影响,构建了晶粒尺寸预测模型,优化了成形工艺参数,给出了工艺参数最佳区间。结果表明,相较于激光功率和扫描速度,送粉速度对晶粒尺寸的影响最为显著;随着成形能量密度的增加,合金晶粒尺寸呈现出先减小后增大的演变趋势;采用回归方程构建的晶粒尺寸-工艺参数关系模型能准确预测不同工艺条件下激光熔化沉积Al-Mg-Sc-Zr合金的平均晶粒尺寸,相对误差小于2%;通过响应面分析得到工艺参数最佳区间为:送粉速度2.8~3 g·min^(-1)、激光功率1000~1050 W、扫描速度4~5 mm·s^(-1)。 展开更多
关键词 激光熔化沉积 AL-MG-SC-zr合金 晶粒尺寸 工艺优化
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氩气和氪气磁控溅射对Zr-Co-RE薄膜微观结构和吸氢性能的影响
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作者 周超 马占吉 +3 位作者 何延春 杨拉毛草 王虎 李得天 《真空与低温》 2024年第1期83-89,共7页
为了获得吸气性能较好的Zr-Co-RE(RE为La和Ce稀土元素)吸气剂薄膜,采用直流磁控溅射方法,分别在氩气和氪气气氛中,通过改变沉积气压研究制备了不同结构的Zr-Co-RE薄膜。运用场发射扫描电镜、X射线衍射仪分析了不同溅射气压下溅射气氛对... 为了获得吸气性能较好的Zr-Co-RE(RE为La和Ce稀土元素)吸气剂薄膜,采用直流磁控溅射方法,分别在氩气和氪气气氛中,通过改变沉积气压研究制备了不同结构的Zr-Co-RE薄膜。运用场发射扫描电镜、X射线衍射仪分析了不同溅射气压下溅射气氛对薄膜结构的影响;采用动态定压法分别测试了在氩气和在氪气中沉积的薄膜的吸氢性能,分析了溅射气氛和薄膜结构对吸氢性能的影响。结果表明,在同等气压下,用氩气溅射沉积的薄膜较致密,用氪气溅射沉积的薄膜表面分布有较多的团簇结构和裂纹结构,薄膜呈明显的柱状结构,且柱状组织间分布着大量的界面和间隙,为气体扩散提供了更多的路径;随着氩气和氪气气压增大,薄膜含有更多的裂纹和间隙结构,连续性柱状结构生长更明显,裂纹更深更宽,比表面积更大,有利于提高薄膜的吸氢性能。 展开更多
关键词 zr-Co-RE薄膜 直流磁控溅射 氪气 溅射气压 微观结构 吸氢性能
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生物可降解挤压态Mg-Sn-Zn-Zr合金组织与腐蚀性能的研究
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作者 刘德学 张全发 +1 位作者 郭菲菲 周田水 《热加工工艺》 北大核心 2024年第15期94-99,共6页
采用气体保护法制备了高强塑性Mg-Sn-Zn-Zr(TZK)合金,然后在不同温度(300、350、400℃)对其进行挤压变形,并对合金的微观组织、物相组成和体外降解行为进行研究。结果表明:300℃挤压后合金的组织为均匀细小的等轴晶,晶粒尺寸最小,为6.57... 采用气体保护法制备了高强塑性Mg-Sn-Zn-Zr(TZK)合金,然后在不同温度(300、350、400℃)对其进行挤压变形,并对合金的微观组织、物相组成和体外降解行为进行研究。结果表明:300℃挤压后合金的组织为均匀细小的等轴晶,晶粒尺寸最小,为6.57μm;析氢量和腐蚀速率最低,耐腐蚀性能最好。随挤压温度升高,合金的晶粒长大,组织中出现孪晶,导致其耐腐蚀性能变差。 展开更多
关键词 Mg-Sn-Zn-zr合金 挤压变形 微观组织 腐蚀性能
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碳酸肼对乏燃料后处理模拟污溶剂中磷酸二丁酯和Zr(Ⅳ)的洗涤行为研究 被引量:1
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作者 王光辉 何辉 矫彩山 《哈尔滨工程大学学报》 EI CAS CSCD 北大核心 2024年第6期1225-1230,共6页
碳酸肼作为碱性无盐试剂对钚铀氧化还原萃取(PUREX)流程的污溶剂的洗涤有广泛的应用前景。本文使用碳酸肼溶液对30%磷酸三丁酯-正十二烷有机溶液中的磷酸二丁酯和Zr(IV)进行洗涤,利用单一变量原则,考察了振荡时间、温度、水相与有机相... 碳酸肼作为碱性无盐试剂对钚铀氧化还原萃取(PUREX)流程的污溶剂的洗涤有广泛的应用前景。本文使用碳酸肼溶液对30%磷酸三丁酯-正十二烷有机溶液中的磷酸二丁酯和Zr(IV)进行洗涤,利用单一变量原则,考察了振荡时间、温度、水相与有机相体积比、碳酸肼质量分数以及磷酸二丁酯质量浓度等因素对去除有机溶液中磷酸二丁酯和Zr(IV)的影响。结果表明:在25℃下振荡洗涤15 min,5%碳酸肼洗涤3次同体积的有机溶液后对0.1 g/L和0.5 g/L的磷酸二丁酯的去除率分别约为98.7%和88.1%。此外,磷酸二丁酯的存在可以促进有机相对Zr(IV)的萃取和保留,当磷酸二丁酯的质量浓度为0时,碳酸肼对Zr(IV)的去除率为98.5%。 展开更多
关键词 碳酸肼 磷酸二丁酯 zr(IV) 去除率 金属保留 洗涤 萃取 无盐试剂
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激光选区熔化Al-Mg-Sc-Zr合金各向组织与损伤容限性能
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作者 冯振宇 陈翥仪 +2 位作者 张雪峰 夏晓宇 邹君 《航空材料学报》 CAS CSCD 北大核心 2024年第1期143-151,共9页
研究激光选区熔化(selective laser melting,SLM)技术成形Al-Mg-Sc-Zr合金材料不同取向的显微组织特征、拉伸和损伤容限性能。结果表明:YZ截面为细小的等轴晶和粗大的柱状晶组成的双峰组织,XY截面由细小的等轴晶组成;0°和90°... 研究激光选区熔化(selective laser melting,SLM)技术成形Al-Mg-Sc-Zr合金材料不同取向的显微组织特征、拉伸和损伤容限性能。结果表明:YZ截面为细小的等轴晶和粗大的柱状晶组成的双峰组织,XY截面由细小的等轴晶组成;0°和90°方向屈服强度、抗拉强度均超过500 MPa,各向异性较小,但堆积层间存在的未熔合缺陷使得90°方向断裂伸长率明显低于0°方向;0°和90°CT试样K_(IC)分别为21.41 MPa·m^(1/2)和20.89 MPa·m^(1/2),在柱状晶区域裂纹扩展阻抗低,导致90°CT试样K_(IC)稍小;显微组织和缺陷是影响裂纹扩展性能各向异性的主要因素,在近门槛区未熔合缺陷起主导作用,当裂纹面平行于水平方向时裂纹扩展速率更快;在稳态扩展区显微组织的影响起主导作用,当裂纹面平行于水平方向时为穿晶断裂,裂纹扩展阻抗较高,裂纹扩展速率较低。 展开更多
关键词 激光选区熔化 AL-MG-SC-zr合金 显微组织 损伤容限性能 各向异性
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