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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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Treatment of a patient with aconitine poisoning using veno-arterial membrane oxygenation:A case report
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作者 Yu-Yao Bian Jin Hou Sudha Khakurel 《World Journal of Clinical Cases》 SCIE 2024年第21期4842-4852,共11页
BACKGROUND Aconitine poisoning is highly prone to causing malignant arrhythmias.The elimination of aconitine from the body takes a considerable amount of time,and during this period,patients are at a significant risk ... BACKGROUND Aconitine poisoning is highly prone to causing malignant arrhythmias.The elimination of aconitine from the body takes a considerable amount of time,and during this period,patients are at a significant risk of death due to malignant arrhythmias associated with aconitine poisoning.CASE SUMMARY A 30-year-old male patient was admitted due to accidental ingestion of aconitinecontaining drugs.Upon arrival at the emergency department,the patient intermittently experienced malignant arrhythmias including ventricular tachycardia,ventricular fibrillation,ventricular premature beats,and cardiac arrest.Emergency interventions such as cardiopulmonary resuscitation and defibrillation were promptly administered.Additionally,veno-arterial extracorporeal membrane oxygenation(VA-ECMO)therapy was initiated.Successful resuscitation was achieved before ECMO placement,but upon initiation of ECMO,the patient experienced recurrent malignant arrhythmias.ECMO was utilized to maintain hemodynamics and respiration,while continuous blood purification therapy for toxin clearance,mechanical ventilation,and hypothermic brain protection therapy were concurrently administered.On the third day of VA-ECMO support,the patient’s respiratory and hemodynamic status stabilized,with only frequent ventricular premature beats observed on electrocardiographic monitoring,and echocardiography indicated recovery of cardiac contractile function.On the fourth day,a significant reduction in toxin levels was observed,along with stable hemodynamic and respiratory functions.Following a successful pump-controlled retrograde trial occlusion test,ECMO assistance was terminated.The patient gradually improved postoperatively and achieved recovery.He was discharged 11 days later.CONCLUSION VA-ECMO can serve as a bridging resuscitation technique for patients with reversible malignant arrhythmias. 展开更多
关键词 poisoning ARRHYTHMIA Blood purification Veno-arterial extracorporeal membrane oxygenation RESUSCITATION Case report
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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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Acquired methemoglobinemia in a third trimester puerpera and her premature infant with sodium nitrite poisoning:A case report
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作者 Dong-Sheng Fei Yang Gao +6 位作者 Xue-Jiao Bao Yu-Jia Tang Yi-Lu Lin Jia-Xi Xu Jia-Ning Zhang Bo-Wen Liu Kai Kang 《World Journal of Clinical Cases》 SCIE 2024年第22期5151-5158,共8页
BACKGROUND The common cause of sodium nitrite poisoning has shifted from previous accidental intoxication by exposure or ingestion of contaminated water and food to recent alarming intentional intoxication as an emplo... BACKGROUND The common cause of sodium nitrite poisoning has shifted from previous accidental intoxication by exposure or ingestion of contaminated water and food to recent alarming intentional intoxication as an employed method of suicide/exit.The subsequent formation of methemoglobin(MetHb)restricts oxygen transport and utilization in the body,resulting in functional hypoxia at the tissue level.In clinical practice,a mismatch of cyanotic appearance and oxygen partial pressure usually contributes to the identification of methemoglobinemia.Prompt recognition of characteristic mismatch and accurate diagnosis of sodium nitrite poisoning are prerequisites for the implementation of standardized systemic interventions.CASE SUMMARY A pregnant woman was admitted to the Department of Critical Care Medicine at the First Affiliated Hospital of Harbin Medical University due to consciousness disorders and drowsiness 2 h before admission.Subsequently,she developed vomiting and cyanotic skin.The woman underwent orotracheal intubation,invasive mechanical ventilation(IMV),and correction of internal environment disturbance in the ICU.Her premature infant was born with a higher-than-normal MetHb level of 3.3%,and received detoxification with methylene blue and vitamin C,supplemental vitamin K1,an infusion of fresh frozen plasma,as well as respiratory support via orotracheal intubation and IMV.On day 3 after admission,the puerpera regained consciousness,evacuated the IMV,and resumed enteral nutrition.She was then transferred to the maternity ward 24 h later.On day 7 after admission,the woman recovered and was discharged without any sequelae.CONCLUSION MetHb can cross through the placental barrier.Level of MetHb both reflects severity of the sodium nitrite poisoning and serves as feedback on therapeutic effectiveness. 展开更多
关键词 Sodium nitrite poisoning METHEMOGLOBINEMIA METHEMOGLOBIN Third trimester puerpera Premature infant Placental barrier Methylene blue 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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THE EXPERIMENTAL STUDY ON BENZENE-POISONED MICE TREATED BY ACUPUNCTURE AND MOXIBUSTION
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作者 Yin Zhifang Chen Hanping Xu Minghai, Shanghai Research Institute of Acupuncture and Meridian, Shanghai 200030, China 《World Journal of Acupuncture-Moxibustion》 1993年第3期48-52,共5页
The subjects of experiment were divided into four groups with twenty femalemice in each.Benzene-poisoned mice were treated with acupuncture or moxibustion at points Dazhui(DU 14),and Mingmen(DU 4).There were obvious d... The subjects of experiment were divided into four groups with twenty femalemice in each.Benzene-poisoned mice were treated with acupuncture or moxibustion at points Dazhui(DU 14),and Mingmen(DU 4).There were obvious difference(all P【O.01)in leucocyte count,myeloid cell count,myeloid cell chromosomal aberration percentage,polychromatophilic erythroblastmicronucleus rate and retrograde vacuoles between before and after treatment.Results showed thatacupuncture or moxibustion was effective in treating benzene-poisoned mice. 展开更多
关键词 Acupuncuture MOXIBUSTION Benzolism benzene-poisoned MICE
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Vanadium supported on graphitic carbon nitride as a heterogeneous catalyst for the direct oxidation of benzene to phenol 被引量:10
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作者 王成 胡丽雅 +3 位作者 王美银 任远航 岳斌 贺鹤勇 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2016年第11期2003-2008,共6页
A series of graphitic carbon nitride supported vanadium catalysts(xV/g-C3N4) with different vanadium contents(x/%) were prepared by impregnation.XRD,FT-IR,TEM,TG-DTG,nitrogen adsorption and XPS characterizations w... A series of graphitic carbon nitride supported vanadium catalysts(xV/g-C3N4) with different vanadium contents(x/%) were prepared by impregnation.XRD,FT-IR,TEM,TG-DTG,nitrogen adsorption and XPS characterizations were conducted which revealed a strong interaction between the vanadium species and g-C3N4 support.8V/g-C3N4 exhibited the highest activity and showed stable recyclability in the benzene hydroxylation reaction with a benzene conversion of 24.6%and phenol selectivity of 99.2%under the optimized conditions.The excellent catalytic performance of xV/g-C3N4 was due to the integration of vanadium species with high catalytic activity and the g-C3N4support in their interaction with the benzene substrate. 展开更多
关键词 Carbon nitride VANADIUM benzene hydroxylation PHENOL IMPREGNATION
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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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Benzene and Toluene Levels Measured with DOAS During Vehicular Restrictions in Beijing 被引量:3
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作者 李素文 谢品华 +1 位作者 韦民红 王江涛 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2015年第1期119-122,I0002,共5页
Measurements of atmospheric benzene and toluene were carried out continuously using dif- ferential optical absorption spectroscopy from August 7 to August 28 in Beijing during the period of vehicular restrictions. The... Measurements of atmospheric benzene and toluene were carried out continuously using dif- ferential optical absorption spectroscopy from August 7 to August 28 in Beijing during the period of vehicular restrictions. The correlations between traffic flows and totals of benzene and toluene were studied during the period of vehicular traffic restrictions from August 17 to August 20 and non-traffic restrictions on August 16 and August 21. The correlation coef- ficient was 0.8 between benzene and toluene. And the calculated daily mean value ratios of benzene to toluene were 0.43-0.50. During the period of vehicular restrictions, traffic flows were reduced about 11.8% and the levels of benzene and toluene were reduced by 11.4% and 12.8%, respectively. The vehicle emissions were recognized as the major sources for atmospheric benzene and toluene in Beijing. 展开更多
关键词 Differential optical absorption spectroscopy benzene and toluene Vehicularrestrictions Tramc emissions Traffic flows
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Effect of Excited-state Substituent Constant on the UV Spectra of 1,4-disubstituted Benzenes 被引量:9
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作者 陈冠凡 曹晨忠 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2009年第4期366-370,447,共6页
A correlation equation between the UV absorption wavenumbers of 1,4-disubstituted benzenes and the excited-state substituent constant was obtained. For 80 sorts of 1,4- disubstituted benzenes, the correlation coeffici... A correlation equation between the UV absorption wavenumbers of 1,4-disubstituted benzenes and the excited-state substituent constant was obtained. For 80 sorts of 1,4- disubstituted benzenes, the correlation coefficient was 0.9805, and the standard deviation was only 672.27 cm^-1. The results imply that the excited-state substituent constant can be used productively for research on UV energy of 1,4-disubstituted benzenes. The present method provides a new avenue to study the UV absorption spectra of aromatic systems with the excited-state substituent constant, and it is helpful to understand the effect of substituent electrostatic effects on the chemical and physical properties of conjugated compounds with multiple substituents in excited state. 展开更多
关键词 Excited-state substituent constant 1 4-disubstituted benzene UV absorption wavenumber Interaction of substituent
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Photoionization Mass Spectrometric and Kinetic Modeling of Low-pressure Pyrolysis of Benzene 被引量:2
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作者 杨玖重 赵龙 +2 位作者 蔡江淮 齐飞 李玉阳 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2013年第3期245-251,I0003,共8页
Pyrolysis of benzene at 30 Torr was studied from 1360 K to 1820 K in this work. Synchrotron vacuum ultraviolet photoionization mass spectrometry was employed to detect the pyroly- sis products such as radicals, isomer... Pyrolysis of benzene at 30 Torr was studied from 1360 K to 1820 K in this work. Synchrotron vacuum ultraviolet photoionization mass spectrometry was employed to detect the pyroly- sis products such as radicals, isomers and polycyclic aromatic hydrocarbons, and measure their mole fraction profiles versus temperature. A low-pressure pyrolysis model of benzene was developed and validated by the experimental results. Rate of production analysis was performed to reveal the major reaction networks in both fuel decomposition and aromatic growth processes. It is concluded that benzene is mainly decomposed via H-abstraction reaction to produce phenyl and partly decomposed via unimolecular decomposition reac- tions to produce propargyl or phenyl. The decomposition process stops at the formation of acetylene and polyyne species like diacetylene and 1,3,5-hexatriyne due to their high thermal stabilities. Besides, the aromatic growth process in the low-pressure pyrolysis of benzene is concluded to initiate from benzene and phenyl, and is controlled by the even carbon growth mechanism due to the inhibited formation of C5 and C7 species which play important roles in the odd carbon growth mechanism. 展开更多
关键词 benzene Low-pressure pyrolysis PAH formation Synchrotron vacuum ultra-violet photoionization mass spectrometry Kinetic model
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配合物Benzene-I_2结构的从头算研究
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作者 李新营 赵永芳 +3 位作者 井孝功 秦艳利 其木苏荣 苏文辉 《原子与分子物理学报》 CAS CSCD 北大核心 2004年第2期265-269,共5页
采用分子轨道从头算方法,对苯用6-311+G 基组,对碘分子用相对论的有效核实势(RECP5s25p5),以及用密度函数方法(B3LYP),计算了配合物Benzene I2可能构形(7种)的结构,总能量和振动频率。经过筛选,同属Cs点群的两种结构是Benzene I2的稳... 采用分子轨道从头算方法,对苯用6-311+G 基组,对碘分子用相对论的有效核实势(RECP5s25p5),以及用密度函数方法(B3LYP),计算了配合物Benzene I2可能构形(7种)的结构,总能量和振动频率。经过筛选,同属Cs点群的两种结构是Benzene I2的稳定结构。自然键轨道(NBO)分析表明,配合物Benzene I2主要是由于苯环的π电子和碘分子的最低空轨道(LUMO)σ 轨道之间的相互作用形成的。本文还给出了这两种结构的势能曲线,并且用含四项Morse函数和一项C6R-6的势能函数进行曲线拟合,给出了相应的拟合参数。 展开更多
关键词 benzene-I2 B3LYP 势能曲线
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Production of Benzene from Lignin through Current Enhanced Catalytic Conversion 被引量:1
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作者 吴小平 范明慧 李全新 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2017年第4期479-486,I0002,共9页
The directional production of benzene is achieved by the current-enhanced catalytic conversion of lignin. The synergistic effect between catalyst and current promotes the depolymerization of lignin and the selective r... The directional production of benzene is achieved by the current-enhanced catalytic conversion of lignin. The synergistic effect between catalyst and current promotes the depolymerization of lignin and the selective recombinant of the functional groups in the aromatic monomers. A high benzene yield of 175 gbenzene/kglignin was obtained with an excellent selectivity of 92.9 C-mol%. The process potentially provides a promising route for the production of basic petrochemical materials or high value-added chemicals using renewable biomass. 展开更多
关键词 benzene Current enhanced catalytic conversion LIGNIN ZEOLITE
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Assessment of Some Density Functional Theory Methods and Force Field Models in Describing Various Interaction Modes of Benzene Dimer 被引量:1
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作者 周余伟 张颖 +2 位作者 吴剑鸣 吴安安 徐昕 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2011年第6期635-639,I0003,共6页
Benzene dimer (bz2) is the simplest prototype of the π-π interactions. Such interactions are ubiquitous in diverse areas of science and molecular engineering. In the present work, we have made assessment on some m... Benzene dimer (bz2) is the simplest prototype of the π-π interactions. Such interactions are ubiquitous in diverse areas of science and molecular engineering. In the present work, we have made assessment on some modern density functional methods including B97-D, BLYP-D3, M06-2X, XYG3, and force field models including CHARMM, AMBER, MM3, AMOEBA on six important interaction modes of bz2. Our results not only highlight the usefulness of these cost-effective methods, which can be used as economic substitutes of the expensive CCSD(T) for complex real-world systems, but also indicate their weakness in the description of the π-π interactions, which points to the future direction for further improvements. 展开更多
关键词 π-π interaction benzene dimer van der Waals DISPERSION XYG3
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Role of penehyclidine in acute organophosphorus pesticide poisoning 被引量:21
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作者 Shi-yuan Yu Yan-xia Gao +8 位作者 Joseph Walline Xin Lu Li-na Zhao Yuan-xu Huang Jiang Tao An-yong Yu Na Ta Ren-ju Xiao Yi Li 《World Journal of Emergency Medicine》 SCIE CAS CSCD 2020年第1期37-47,共11页
BACKGROUND:Penehyclidine is a newly developed anticholinergic agent.We aimed to investigate the role of penehyclidine in acute organophosphorus pesticide poisoning(OP)patients.METHODS:We searched the Pubmed,Cochrane l... BACKGROUND:Penehyclidine is a newly developed anticholinergic agent.We aimed to investigate the role of penehyclidine in acute organophosphorus pesticide poisoning(OP)patients.METHODS:We searched the Pubmed,Cochrane library,EMBASE,Chinese National Knowledge Infrastructure(CNKI),Chinese Biomedical literature(CBM)and Wanfang databases.Randomized controlled trials(RCTs)recruiting acute OP patients were identifi ed for meta-analysis.Main outcomes included cure rate,mortality rate,time to atropinization,time to 60%normal acetylcholinesterase(AchE)level,rate of intermediate syndrome(IMS)and rate of adverse drug reactions(ADR).RESULTS:Sixteen RCTs involving 1,334 patients were identifi ed.Compared with the atropineor penehyclidine-alone groups,atropine combined with penehyclidine significantly increased the cure rate(penehyclidine+atropine vs.atropine,0.97 vs.0.86,RR 1.13,95%CI[1.07–1.19];penehyclidine+atropine vs.penehyclidine,0.93 vs.0.80,RR 1.08,95%CI[1.01–1.15])and reduced the mortality rate(penehyclidine+atropine vs.atropine,0.015 vs.0.11,RR 0.17,95%CI[0.06–0.49];penehyclidine+atropine vs.penehyclidine,0.13 vs.0.08,RR 0.23,95%CI[0.04–1.28]).Atropine combined with penehyclidine in OP patients also helped reduce the time to atropinization and AchE recovery,the rate of IMS and the rate of ADR.Compared with a single dose of atropine,a single dose of penehyclidine also signifi cantly elevated the cure rate,reduced times to atropinization,AchE recovery,and rate of IMS.CONCLUSION:Atropine combined with penehyclidine benefi ts OP patients by enhancing the cure rate,mortality rate,time to atropinization,AchE recovery,IMS rate,total ADR and duration of hospitalization.Penehyclidine combined with atropine is likely a better initial therapy for OP patients than atropine alone. 展开更多
关键词 PENEHYCLIDINE ORGANOPHOSPHORUS PESTICIDE poisoning META-ANALYSIS
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