1.Clinical and Laboratory Characteristic Analysis of Patients with Newly Diagnosed Monoclonal Gammopathy Combined with Anemia.
Han QIAN ; Yue-Xia WU ; Min YANG ; Yu-Ting HU ; Yu-Jie KONG ; Qian LIU ; Ying XU
Journal of Experimental Hematology 2025;33(2):587-592
OBJECTIVE:
To study the clinical and laboratory characteristics of monoclonal gammopathy anemia and explore the risk factors associated with anemia in monoclonal gammopathy.
METHODS:
A retrospective analysis was conducted on 5 539 patients who underwent immunofixation electrophoresis at the First Affiliated Hospital of Chengdu Medical College from January 2016 to February 2024. A total of 351 newly diagnosed M protein positive patients were selected as the study subjects, including 270 in the anemia group and 81 in the non-anemia group. Laboratory test results were compared between the two groups, and logistic regression models were used to analyze the risk factors for anemia. ROC curve analysis was performed to evaluate the predictive value of risk factors for anemia in monoclonal gammopathy.
RESULTS:
The proportion of non-anemic patients was 23.1% (81/351), with a median age of 67(60-75) years; the proportion of anemic patients was 76.9% (270/351), with a median age of 70(63-75) years. The total protein, globulin, urea, creatinine, uric acid, β2-microglobulin, and ceruloplasmin levels in the anemia group were higher than those in the non-anemia group ( P < 0.05), while albumin, neutrophil count, lymphocyte count, monocyte count, complement C3, complement C4, haptoglobin, and transferrin levels were lower in the non-anemia group ( P < 0.05). After adjustment, multivariate logistic regression analysis shows that elevated GLB, increased β2-MG, decreased ANC, and reduced complement C3 were independent risk factors for anemia in monoclonal gammopathy ( P < 0.05). ROC curve analysis demonstrates that GLB, β2-MG, ANC, and complement C3 had good predictive value for anemia associated with monoclonal gammopathy.
CONCLUSION
Elevated GLB, increased β2-MG, decreased ANC, and reduced complement C3 are independent risk factors for anemia in monoclonal gammopathy (P < 0.05). The combined assessment of these four factors has good predictive value for anemia in monoclonal gammopathy.
Humans
;
Retrospective Studies
;
Anemia/complications*
;
Aged
;
Middle Aged
;
Paraproteinemias/diagnosis*
;
Risk Factors
;
Male
;
Female
;
Logistic Models
;
ROC Curve
;
Complement C3
2.Clinical Characteristics of Adult Acute Myeloid Leukemia Patients with NUP98::HOXA9 Fusion Gene.
Hai-Xia CAO ; Ya-Min WU ; Shu-Juan WANG ; Zhi-Dan CHEN ; Jing-Han HU ; Xiao-Qian GENG ; Fang WANG ; Ling SUN ; Zhong-Xing JIANG ; Zhi-Lei BIAN
Journal of Experimental Hematology 2025;33(5):1241-1247
OBJECTIVE:
To investigate the clinical characteristics, treatment and prognosis of adult AML patients with NUP98::HOXA9 fusion gene.
METHODS:
From May 2017 to October 2023, among 2 113 AML patients who visited the Hematology Department of our hospital, patients with NUP98 rearrangements were screened. The clinical characteristics, chromosome karyotypes, immunophenotypes, gene mutations, treatment efficacy and prognosis of the patients with NUP98::HOXA9 positive were analyzed.
RESULTS:
Among the 2 113 AML patients, there were 18 cases with NUP98 rearrangement, including 14 NUP98::HOXA9 positive cases, with a detection rate of 0.66% (14/2 113). The median age of the NUP98::HOXA9 positive patients was 42.5 (23-64) years old. The most common chromosome karyotype was t(7; 11)(p15; p15). The immunophenotypes of all patients expressed CD13, CD33, CD117 and CD38, and most patients expressed CD34 and cMPO, while only a few expressed HLA-DR. Second-generation sequencing (NGS) was performed to detect genetic mutations associated with leukemia in all 14 patients, and the genes exhibiting a high frequency of mutation were WT1 (10/14), TET2 (7/14), and FLT3-ITD (6/14). Additionally, mutations were also observed in KRAS/NRAS, IDH1, and KIT. Of the 13 patients who received treatment, 9 achieved complete remission (CR), and all 3 patients who received azacytidine(AZA)+ venetoclax (VEN) regimen achieved CR after the first course of treatment. Within this cohort, 6 patients were classified as relapsed/refractory (6/13). 4 patients underwent allogeneic hematopoietic stem cell transplantation (allo-HSCT), of which two achieved long-term survival. The median follow-up time was 12 (2.1-65.0) months, while the median overall survival (OS) and relapse-free survival (RFS) were recorded as 11.4 months and 9.6 months, respectively.
CONCLUSION
The most common type of NUP98 rearrangement in adults AML patients is NUP98::HOXA9 , which is often accompanied by somatic mutations in WT1, TET2, and FLT3-ITD. These patients are prone to relapse, have short survival time, and generally face poor prognoses. Hopefully, utilization of the AZA+VEN regimen is anticipated to enhance the rate of induced remission in the patients, and some patients may prolong their survival through allo-HSCT. However, more effective treatment methods are still needed to improve the overall prognosis of these patients.
Humans
;
Adult
;
Leukemia, Myeloid, Acute/genetics*
;
Middle Aged
;
Prognosis
;
Nuclear Pore Complex Proteins/genetics*
;
Oncogene Proteins, Fusion/genetics*
;
Mutation
;
Male
;
Female
;
Young Adult
;
Homeodomain Proteins/genetics*
3.Observation on the therapeutic effect of pre-reduction with traditional Chinese medicine bone-setting manipulation in the treatment of supracondylar fracture of humerus in children
Min WU ; Qunqun ZENG ; Xiangping DU ; Jian LI ; Xia LI
China Modern Doctor 2025;63(22):9-11,15
Objective To explore the effect of delayed Kirschner wire fixation after emergency pre-reduction with traditional Chinese medicine bone-setting manipulation in the treatment of supracondylar fracture of humerus in children.Methods Sixty patients with supracondylar fracture of humerus admitted to Jiangxi Provincial Children's Hospital from June 2022 to June 2023 were selected and divided into observation group and control group according to the random number table method,with 30 cases in each group.The observation group adopted emergency pre-reduction with traditional Chinese medicine bone-setting manipulation and delayed surgical reduction,and the control group underwent delayed surgical reduction.The operation time,intraoperative fluoroscopy frequency,reduction condition,postoperative complications,elbow joint function at the last follow-up of two groups of children were compared.Results The operation time of children in observation group was significantly shorter than that in control group,and the number of fluoroscopy was significantly less than that in control group(P<0.05).The proportion of anatomical reduction in observation group was significantly higher than that in control group(P<0.05).There was no statistically significant difference in fracture healing time between two groups of children(P>0.05).Neither of two groups of children had conversion incision,postoperative re-displacement of fractures,nerve injury,infection,cubitus varus or elbow valgus deformity,etc..At the last follow-up,there was no statistically significant difference in the excellent and good rate of elbow joint function between two groups of children(P=0.301).Conclusion Emergency traditional Chinese medicine bone-setting manipulation in the treatment of supracondylar fracture of humerus in children can shorten the operation time,reduce the radiation dose,alleviate the burden of emergency medical treatment,have no obvious complications,and have a good effect.It is worthy of promotion.
4.A multicenter retrospective study on clinicopathological features, gene variation profiles and prognostic analysis of previously untreated diffuse large B - cell lymphoma
Yongning JIANG ; Jie ZHANG ; Yaping ZHANG ; Yi XIA ; Yi MIAO ; Haiwen NI ; Jinning SHI ; Xiaohui ZHANG ; Min XU ; Haiying HUA ; Yun ZHUANG ; Wenzhong WU ; Maozhong XU ; Xiaoyan XIE ; Zhuxia JIA ; Yuqing MIAO ; Min ZHAO ; Jianyong LI ; Wenyu SHI
Chinese Journal of Medical Genetics 2025;42(9):1069-1077
Objective:To explore the impact of age on the genetic variant spectrum and prognosis of patients with previously untreated Diffuse large B-cell lymphoma (DLBCL).Methods:A retrospective analysis was conducted on the clinical data and follow-up information of 254 previously untreated DLBCL patients from 14 hospitals in the Jiangsu Cooperative Lymphoma Group (JCLG) enrolled from July 2018 and July 2023. Following extraction of DNA from tumor tissue samples, next-generation sequencing (NGS) technique was employed to analyze the genetic variant spectrum of the DLBCL patients, with an evaluation of the relationship between age and genetic variants as well as prognosis. This study was approved by the Medical Ethics Committee of the Affiliated Hospital of Nantong University (Ethics No.: 2023-K048-01).Results:The median age of the 254 DLBCL patients was 62 years old, with 55% of patients aged 60 years or above. Clinical evaluation showed that younger (< 60 years) patients had higher complete response (CR) (70% vs. 59%), and objective response rate (ORR) (88% vs. 79%) than older patients, though the difference between the two groups was not statistically. Survival analysis indicated that both the five-year overall survival (OS) (82.7% vs. 71.7%, P=0.006) and progression-free survival (PFS) (70.6% vs. 50.2%, P<0.05) rates were significantly higher in younger patients. NGS showed that 99.6% of the patients harbored genetic variants, with PIM1, KMT2D, TP53, MYD88, and CD79B being the most common genes. Age significantly affected the variant frequency of certain genes, with MYC variants serving an adverse prognostic factor for OS in younger patients ( P=0.001), while TP53 ( P=0.024) and BCL2 ( P=0.002) variants significantly impacted OS in older patients. Prognostic analysis identified age ≥ 60 years ( HR=3.439, 95% CI=1.318~9.874), presence of B symptoms ( HR = 2.871, 95% CI=1.133~7.307), and elevated lactate dehydrogenase ( HR=3.528, 95% CI=1.231~10.66) as independent adverse prognostic factors. Conclusion:Age, genetic variants, and clinical factors may significantly affect the prognosis of the DLBCL patients. Younger patients have better survival compared to older patients. Variants of the MYC, BCL2, and TP53 genes are closely associated with poor prognosis.
5.Development and reliability and validity test of post competence assessment scale for nurses in the health management (physical examination) center
Yue LI ; Hua GUAN ; Xiaodan ZHOU ; Xia LUO ; Haiyan WU ; Kunhong MIN ; Rong JIANG
Chinese Journal of Health Management 2025;19(9):728-734
Objective:To develop a post competence assessment scale for nurses in the health management (physical examination) center and assess its reliability and validity.Methods:This study adopted an empirical approach. A total of 801 nurses from the health management (physical examination) center were recruited to participate in this study. A research team was formed in August 2024. This team transformed the previously constructed core competence evaluation index system for health management specialist nurses in the health management (physical examination) center (comprising 6 first-level indicators and 70 third-level indicators) into a preliminary post competence assessment scale. Seven experts evaluated the content validity of the scale. In September 2024, a pilot survey was conducted among 27 nurses from the health management (physical examination) center of Sichuan Provincial People′s Hospital using convenience sampling. From October to November 2024, the first main survey was administered to 385 nurses of health management (physical examination) center across 54 cities in China using both convenience sampling and snowball sampling methods, followed by exploratory factor analysis (EFA). Subsequently, utilizing the refined scale obtained after eliminating certain items, a second main survey was conducted among 389 nurses in the health management (physical examination) center, followed by a confirmatory factor analysis (CFA). The reliability of the final scale was assessed using Cronbach′s α coefficient, split-half reliability, composite reliability, and test-retest reliability.Results:The finalized scale for nurses′ post competency in health management (physical examination) center comprises five dimensions—basic nursing service competency, health management practice competency, knowledge integration competency, professional development competency, and professional attitude—with a total of 57 items. The item level content validity index (I-CVI) of the items of the content validity display scale ranged from 0.857 to 1.000, and the content validity index of each dimension ranged from 0.984 to 1.000. The scale-level Content Validity index/average (S-CVI/Ave) was 0.995. The contribution rate of the 6 factors extracted by EFA was 74.07%. After group discussion and CFA, the scale of the 5-factor structural equation model was constructed. The total Cronbach′s α coefficient of the scale was 0.986, the split-half reliability was 0.865, the composite reliability was 0.960-0.980, the total table test-retest reliability was 0.762, and the test-retest reliability of each dimension was 0.681-0.731.Conclusion:The developed assessment scale for assessing the post competence of nurses in the health management (physical examination) center demonstrates excellent reliability and validity.
6.Consensus on informed consent for orthodontic treatment
Yang CAO ; Bing FANG ; Zuolin JIN ; Hong HE ; Yuxing BAI ; Lin WANG ; Haiping LU ; Zhihe ZHAO ; Tianmin XU ; Weiran LI ; Min HU ; Jinlin SONG ; Jun WANG ; Fang JIN ; Ding BAI ; Xianglong HAN ; Yuehua LIU ; Bin YAN ; Jie GUO ; Jiejun SHI ; Yongming LI ; Zhihua LI ; Xiuping WU ; Jiangtian HU ; Linyu XU ; Lin LIU ; Yi LIU ; Yanqin LU ; Wensheng MA ; Shuixue MO ; Liling REN ; Shuxia CUI ; Yongjie FAN ; Jianguang XU ; Lulu XU ; Zhijun ZHENG ; Peijun WANG ; Rui ZOU ; Chufeng LIU ; Lunguo XIA ; Li HU ; Weicai WANG ; Liping WU ; Xiaoxing KOU ; Jiali TAN ; Yuanbo LIU ; Bowen MENG ; Yuantao HAO ; Lili CHEN
Chinese Journal of Stomatology 2025;60(12):1327-1336
This consensus was developed by the Orthodontic Society of the Chinese Stomatological Association to provide a systematic, scientific, and practical guideline for informed consent in orthodontic care. Orthodontic treatment is typically lengthy, highly individualized, and involves multiple factors such as growth and development, occlusal function, and facial esthetics. Rapid technological advances and diverse risk profiles make the traditional reliance on orthodontist experience or institutional templates insufficient to ensure patients′ full understanding and autonomous decision-making. To address this, the expert panel conducted extensive reviews of domestic and international guidelines, analyzed representative dispute cases, and performed multicenter patient-clinician surveys. Using a multi-round Delphi method, the group established a standardized informed consent framework covering the initial consultation, treatment, and retention phases. The consensus emphasizes that informed consent is not only a fundamental legal and ethical requirement but also a key step in building trust, improving patient compliance, and enhancing treatment satisfaction. Orthodontists should clearly and comprehensively explain treatment plans, potential risks, uncertainties, and associated costs, while respecting the autonomy of patients or guardians, and maintain continuous communication and dynamic evaluation throughout the treatment process. The release of this consensus provides unified and authoritative guidance for clinical orthodontics, helping to standardize informed consent, enhance its transparency, safeguard patient rights, reduce medical risks, and promote high-quality, sustainable development of orthodontic practice.
7.A study of attention and interpretation therapy based on Swanson′s caring theory in children with adolescent epilepsy
Shan ZENG ; Huayan LIU ; Lingfang TAN ; Yuewei CHEN ; Min YI ; Xia WU ; Li XU
Chinese Journal of Practical Nursing 2025;41(9):641-650
Objective:To explore the application effect of the attention and interpretation therapy based on Swanson′s caring theory in adolescents with epilepsy, aiming to reduce negative emotions and improve self-management levels in children.Methods:This study was a quasi-experimental research. A convenience sampling method was used to select 78 adolescents with epilepsy who were admitted to the Department of Neurology, the Affiliated Children′s Hospital of Xiangya School of Medicine, Central South University (Hunan Children′s Hospital) from March 1 to August 31, 2023. The participants were assigned into two groups, the control group ( n=39) and the intervention group ( n=39), using a random number table. The control group received standard anti-epileptic treatment and routine nursing care, while the intervention group received the same treatment and care with the addition of a caring team providing attention and interpretation therapy based on Swanson′s caring theory. Assessments were made at three time points: before the intervention, 4 weeks after the intervention, and 12 weeks after the intervention. The Depression-Anxiety-Stress Scale (DASS-21), Epilepsy Self-Management Scale (ESMS), and Pediaric Quality of Life Inventory Measurement Methods (PedsQL TM4.0) were used to assess the participants′ scores. Results:In the control group, 23 were male and 16 were female, with aged of (13.49 ± 1.43) years. In the intervention group, 24 were male and 15 were female, with aged of (13.51 ± 1.45) years. After 4 weeks of intervention, the scores of depression, anxiety, and stress on the DASS-21 for the intervention group were (9.32 ± 2.04), (6.79 ± 2.44), and (13.63 ± 2.67), respectively, which were lower than those of the control group: (10.43 ± 2.27), (8.43 ± 2.75) and (16.05 ± 3.32); the scores of ESMS and PedsQL TM4.0 in the intervention group were (66.66 ± 10.87) and (73.63 ± 9.85), respectively, which were higher than those of the control group: (60.70 ± 10.24) and (67.27 ± 12.33), the differences were statistically significant ( t values were -2.47 to 3.49, all P<0.05). After 12 weeks of intervention, the scores on the DASS-21 for the intervention group were (5.47 ± 1.66), (3.37 ± 1.68) and (8.42 ± 2.24) for depression, anxiety and stress, respectively, which were lower than those of the control group: (8.03 ± 1.98), (6.06 ± 2.64) and (11.28 ± 3.21) ;the scores for ESMS and PedsQL TM4.0 in the intervention group were (74.66 ± 9.15) and (85.24 ± 7.00), respectively, which were higher than those of the control group: (65.36 ± 10.86) and (75.67 ± 11.39), the differences were statistically significant ( t values were -4.33 to 6.03, all P<0.05). Additionally, there were statistically significant differences in the DASS-21 depression, anxiety, and stress scores, ESMS, and PedsQL TM4.0 scores across the different time points ( F values ranged from 4.65 to 1 134.03, all P<0.05). Conclusions:Attention and interpretation therapy based on Swanson′s caring theory can effectively reduce negative emotions in adolescents with epilepsy, improve their self-management skills, and further enhance their quality of life.
8.Application of nursing coordination process based on healthcare failure mode and effect analysis management in the treatment of ST-segment elevation myocardial infarction patients
Lingli WU ; Yueli CHEN ; Qun WANG ; Xia ZUO ; Min YU
Chinese Journal of Practical Nursing 2025;41(16):1230-1235
Objective:To explore the application effect of nursing coordination process based on healthcare failure mode and effect analysis (HFMEA) management in the treatment of patients with acute ST-segment elevation myocardial infarction (STEMI), so as to improve clinical treatment efficiency.Methods:In this prospective cohort study, STEMI patients requiring emergency percutaneous coronary intervention (PCI) admitted to the Department of Emergency, Subei People′s Hospital of Jiangsu Province from January to May 2024 were selected by random sampling method. According to the admission time, patients were divided into control group (from January to February 2024, received routine emergency process) and experimental group (from April to May 2024, received nursing coordination process based on HFMEA management). The triage evaluation time, reception time, reporting time of the first electrocardiogram, coming out time of troponin T results, improvement time of preoperative preparation, treatment effect (length of hospital stay, success rate of treatment, nosocomial mortality) and emergency physicians′ satisfaction with nursing work in the two groups were compared.Results:In the 100 STEMI patients, there were 48 cases in the control group, with 23 males and 25 females, aged (61.64 ± 4.37) years old. There were 52 cases in the experimental group, with 26 males and 26 females, aged (62.11 ± 4.61) years old. The triage evaluation time, reception time, reporting time of the first electrocardiogram, coming out time of troponin T results and improvement time of preoperative preparation in the experimental group were (1.65 ± 0.57), (2.46 ± 0.57), (7.58 ± 1.32), (16.43 ± 2.16), (46.18 ± 3.94) min, shorter than (2.48 ± 0.69), (3.41 ± 0.63), (10.69 ± 1.24), (18.66 ± 2.37), (54.37 ± 4.11) min in the control group, the differences were statistically significant ( t values were 4.92-12.12, all P<0.05). The length of hospital stay and nosocomial mortality in the experimental group were (10.16 ± 2.34) d, 3.85% (2/52), lower than (12.38 ± 2.09) d, 16.67% (8/48) in the control group, and success rate of treatment was 90.38% (47/52), higher than 75.00% (36/48) in the control group, the differences were statistically significant ( t=4.99, χ2=4.56, 4.19, all P<0.05). The emergency physicians′ satisfaction with nursing work in the experimental group was (79.43 ± 6.00) points, higher than (64.44 ± 6.54) points in the control group, the difference was statistically significant ( t=11.95, P<0.05). Conclusions:Nursing coordination process based on HFMEA management can effectively improve emergency efficiency in STEMI patients, shorten emergency time and reduce nosocomial mortality.
9.A multicenter retrospective study on the clinicopathological features, genetic variant profiles and prognosis of patients with previously untreated Diffuse large B-cell lymphoma.
Yongning JIANG ; Jie ZHANG ; Yaping ZHANG ; Yi XIA ; Yi MIAO ; Haiwen NI ; Jinning SHI ; Xiaohui ZHANG ; Min XU ; Haiying HUA ; Yun ZHUANG ; Wenzhong WU ; Maozhong XU ; Xiaoyan XIE ; Zhuxia JIA ; Yuqing MIAO ; Min ZHAO ; Jianyong LI ; Wenyu SHI
Chinese Journal of Medical Genetics 2025;42(9):1069-1077
OBJECTIVE:
To explore the impact of age on the genetic variant spectrum and prognosis of patients with previously untreated Diffuse large B-cell lymphoma (DLBCL).
METHODS:
A retrospective analysis was conducted on the clinical data and follow-up information of 254 previously untreated DLBCL patients from 14 hospitals in the Jiangsu Cooperative Lymphoma Group (JCLG) enrolled from July 2018 and July 2023. Following extraction of DNA from tumor tissue samples, next-generation sequencing (NGS) technique was employed to analyze the genetic variant spectrum of the DLBCL patients, with an evaluation of the relationship between age and genetic variants as well as prognosis. This study was approved by the Medical Ethics Committee of the Affiliated Hospital of Nantong University (Ethics No.: 2023-K048-01).
RESULTS:
The median age of the 254 DLBCL patients was 62 years old, with 55% of patients aged 60 years or above. Clinical evaluation showed that younger (< 60 years) patients had higher complete response (CR) (70% vs. 59%), and objective response rate (ORR) (88% vs. 79%) than older patients, though the difference between the two groups was not statistically. Survival analysis indicated that both the five-year overall survival (OS) (82.7% vs. 71.7%, P = 0.006) and progression-free survival (PFS) (70.6% vs. 50.2%, P < 0.05) rates were significantly higher in younger patients. NGS showed that 99.6% of the patients harbored genetic variants, with PIM1, KMT2D, TP53, MYD88, and CD79B being the most common genes. Age significantly affected the variant frequency of certain genes, with MYC variants serving an adverse prognostic factor for OS in younger patients (P = 0.002), while TP53 (P = 0.024) and BCL2 (P = 0.002) variants significantly impacted OS in older patients. Prognostic analysis identified age ≥ 60 years (HR = 3.439, 95%CI: 1.318~9.874), presence of B symptoms (HR = 2.871, 95%CI = 1.133~7.307), and elevated lactate dehydrogenase (HR = 3.528, 95%CI = 1.231~10.66) as independent adverse prognostic factors.
CONCLUSION
Age, genetic variants, and clinical factors may significantly affect the prognosis of the DLBCL patients. Younger patients have better survival compared to older patients. Variants of the MYC, BCL2, and TP53 genes are closely associated with poor prognosis.
Humans
;
Lymphoma, Large B-Cell, Diffuse/diagnosis*
;
Middle Aged
;
Female
;
Male
;
Retrospective Studies
;
Aged
;
Prognosis
;
Adult
;
Aged, 80 and over
;
High-Throughput Nucleotide Sequencing
;
Young Adult
;
Adolescent
;
Genetic Variation
10.Quantification of Atmospheric Total Reactive Nitrogen Oxides by Thermal Decomposition-Broadband Cavity Enhanced Absorption Spectroscopy
Dou SHAO ; Min QIN ; Wu FANG ; Bao-Bin HAN ; Ke TANG ; Jian-Ye XIE ; Xia-Dan ZHAO ; Zhi-Tang LIAO ; En-Bo REN
Chinese Journal of Analytical Chemistry 2025;53(3):387-396
Nitrogen oxides(NOx=NO+NO2)are important precursors of ozone(O3),and NOx and its oxides together constitute reactive nitrogen oxides(NOy)in the atmosphere.A comprehensive understanding of the total NOy level in the atmosphere is of great significance for a deeper understanding of the atmospheric nitrogen cycle and oxidation,as well as for formulating strategies for air pollution prevention and control.In this work,a thermal decomposition-broadband cavity enhanced absorption spectroscopy(TD-BBCEAS)technique for online measurement of total NOy in the atmosphere was developed.With this method,the NOy was efficiently converted into NO2,and the total NOy concentration in the atmosphere was indirectly obtained by measuring NO2.Focusing on the key factors affecting the measurement of total NOy,the influence of NO titration efficiency and other NOy component TD efficiency on measurement accuracy was emphasized.By changing the oxygen(O2)flow rate through the mercury lamp to alter the O3 concentration for titrating NO,the conversion efficiency of NO was evaluated.At O2 flow rate of 6 mL/min,the conversion efficiency of NO was greater than 99%.TD efficiency testing and analysis on NO2,peroxyacetyl nitrate(PAN),nitric acid(HNO3),and nitrous acid(HONO),which account for a large proportion of atmospheric NOy components,was carried out using 680℃as the optimal TD temperature for efficient conversion of NOy.With NO and HONO sample gases as typical verification gases,the conversion efficiency of NOy and the accuracy of NOy measurement by TD-BBCEAS system were verified by switching the on and off modes of mercury lamp and TD device.At integration time of 60 s,the detection limit of the system for NOy was 2.83×1010 molecules/cm3(60 s,2σ).A comparative measurement of actual atmospheric NOy was conducted between the TD-BBCEAS system and the NOy analyzer.The observation results showed a correlation coefficient(R2)of 0.98 and a slope of 0.93,further verifying the feasibility and accuracy of applying the TD-BBCEAS system to measurement of total NOy.

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