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Numerical Analysis of Explosion Characteristics of Vent Gas From 18650 LiFePO_(4) Batteries With Different States of Charge
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作者 Shi-Lin Wang Xu Gong +5 位作者 li-na liu Yi-Tong Li Chen-Yu Zhang Le-Jun Xu Xu-Ning Feng Huai-Bin Wang 《电化学(中英文)》 CAS 北大核心 2024年第8期28-35,共8页
The combustion and explosion characteristics of lithium-ion battery vent gas is a key factor in determining the fire hazard of lithium-ion batteries.Investigating the combustion and explosion hazards of lithium-ion ba... The combustion and explosion characteristics of lithium-ion battery vent gas is a key factor in determining the fire hazard of lithium-ion batteries.Investigating the combustion and explosion hazards of lithium-ion batteries vent gas can provide guidance for rescue and protection in explosion accidents in energy storage stations and new energy vehicles,thereby promoting the application and development of lithium-ion batteries.Based on this understanding and combined with previous research on gas production from lithium-ion batteries,this article conducted a study on the combustion and explosion risks of vent gas from thermal runaway of 18650 LFP batteries with different states of charge(SOCs).The explosion limit of mixed gases affected by carbon dioxide inert gas is calculated through the“elimination”method,and the Chemkin-Pro software is used to numerically simulate the laminar flame speed and adiabatic flame temperature of the battery vent gas.And the concentration of free radicals and sensitivity coefficients of major elementary reactions in the system are analyzed to comprehensively evaluate the combustion explosion hazard of battery vent gas.The study found that the 100%SOC battery has the lowest explosion limit of the vent gas.The inhibitory elementary reaction sensitivity coefficient in the reaction system is lower and the concentration of free radicals is higher.Therefore,it has the maximum laminar flame speed and adiabatic flame temperature.The combustion and explosion hazard of battery vent gas increases with the increase of SOC,and the risk of explosion is the greatest and most harmful when SOC reaches 100%.However,the related hazards decrease to varying degrees with overcharging of the battery.This article provides a feasible method for analyzing the combustion mechanism of vent gas from lithium-ion batteries,revealing the impact of SOC on the hazardousness of battery vent gas.It provides references for the safety of storage and transportation of lithium-ion batteries,safety protection of energy storage stations,and the selection of related fire extinguishing agents. 展开更多
关键词 Combustion and explosion characteristics Explosion limit Laminar flame speed Adiabatic flame temperature Sensitivity analysis
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Nomogram for predicting the risk of anxiety and depression in patients with non-mild burns
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作者 Jie Chen Jian-Fei Zhang +7 位作者 Xia Xiao Yu-Jun Tang He-Jin Huang Wen-Wen Xi li-na liu Zheng-Zhou Shen Jian-Hua Tan Feng Yang 《World Journal of Psychiatry》 SCIE 2024年第8期1233-1243,共11页
BACKGROUND Post-burn anxiety and depression affect considerably the quality of life and recovery of patients;however,limited research has demonstrated risk factors associated with the development of these conditions.A... BACKGROUND Post-burn anxiety and depression affect considerably the quality of life and recovery of patients;however,limited research has demonstrated risk factors associated with the development of these conditions.AIM To predict the risk of developing post-burn anxiety and depression in patients with non-mild burns using a nomogram model.METHODS We enrolled 675 patients with burns who were admitted to The Second Affiliated Hospital,Hengyang Medical School,University of South China between January 2019 and January 2023 and met the inclusion criteria.These patients were randomly divided into development(n=450)and validation(n=225)sets in a 2:1 ratio.Univariate and multivariate logistic regression analyses were conducted to identify the risk factors associated with post-burn anxiety and depression dia-gnoses,and a nomogram model was constructed.RESULTS Female sex,age<33 years,unmarried status,burn area≥30%,and burns on the head,face,and neck were independent risk factors for developing post-burn anxiety and depression in patients with non-mild burns.The nomogram model demonstrated predictive accuracies of 0.937 and 0.984 for anxiety and 0.884 and 0.923 for depression in the development and validation sets,respectively,and good predictive per-formance.Calibration and decision curve analyses confirmed the clinical utility of the nomogram.CONCLUSION The nomogram model predicted the risk of post-burn anxiety and depression in patients with non-mild burns,facilitating the early identification of high-risk patients for intervention and treatment. 展开更多
关键词 BURN Post-burn anxiety Depression Risk prediction Nomogram model
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雷珠单抗或加减驻景方对形觉剥夺性近视豚鼠眼轴和脉络膜厚度的短期影响 被引量:6
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作者 刘俐娜 钟兴武 +4 位作者 刘红山 王丹阳 徐家窈 劳伟 吴挺飞 《国际眼科杂志》 CAS 北大核心 2020年第4期599-602,共4页
目的:观察形觉剥夺性豚鼠近视模型中给予中药驻景方或雷珠单抗注射液干预后屈光度、眼轴长度和脉络膜厚度的短期变化。方法:取出生2wk的豚鼠60只,右眼戴头套诱导形觉剥夺性近视(FDM)动物模型。2wk后随机分为雷珠单抗组、驻景方组和生理... 目的:观察形觉剥夺性豚鼠近视模型中给予中药驻景方或雷珠单抗注射液干预后屈光度、眼轴长度和脉络膜厚度的短期变化。方法:取出生2wk的豚鼠60只,右眼戴头套诱导形觉剥夺性近视(FDM)动物模型。2wk后随机分为雷珠单抗组、驻景方组和生理盐水组(各组n=20)。雷珠单抗组第1d玻璃体腔注射雷珠单抗注射液0.02mg 1次,驻景方组给予加减驻景方灌胃3.285g/(kg·d)(1.5mL/d)共7d,生理盐水组给予等量生理盐水灌胃。分别测量记录三组豚鼠给药前和给药后1、3d,1wk的屈光度、眼轴长度和脉络膜厚度。结果:雷珠单抗组给药前后的各值均无差异(P>0.05)。驻景方组和生理盐水组给药后1、3d的屈光度明显降低、眼轴长度缩短、脉络膜厚度增厚(P<0.05),且3d时两组的各值变化最明显,但均在1wk时恢复到给药前的水平。三组间给药1、3d时生理盐水组和驻景方组的屈光度均低于雷珠单抗组,且眼轴长度较短,脉络膜厚度较厚(P<0.05),给药3d时生理盐水组的各值变化最明显(P<0.05)。给药1wk时三组间各指标均无差异(P>0.05)。结论:形觉剥夺性近视恢复期有一个短暂的脉络膜增厚时期,雷珠单抗注射液全程明显抑制了形觉剥夺性近视恢复期脉络膜的增厚,驻景方在3d时开始出现轻微的增厚抑制,均只持续了短暂的1wk时间。 展开更多
关键词 近视 驻景方 雷珠单抗 屈光度 眼轴长度 脉络膜厚度 豚鼠 血管内皮生长因子
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屈光参差儿童单眼配戴角膜塑形镜后调节功能的变化 被引量:12
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作者 刘俐娜 钟兴武 +2 位作者 胡施思 罗静红 陈永青 《国际眼科杂志》 CAS 北大核心 2020年第6期1040-1043,共4页
目的:观察屈光参差儿童单眼配戴角膜塑形镜后双眼调节功能的变化,探讨调节在角膜塑形镜控制近视进展中的机制。方法:前瞻性自身对照研究,对2016-09/2018-09在我院门诊就诊的屈光参差儿童单眼配戴角膜塑形镜的青少年22例44眼,将配戴角膜... 目的:观察屈光参差儿童单眼配戴角膜塑形镜后双眼调节功能的变化,探讨调节在角膜塑形镜控制近视进展中的机制。方法:前瞻性自身对照研究,对2016-09/2018-09在我院门诊就诊的屈光参差儿童单眼配戴角膜塑形镜的青少年22例44眼,将配戴角膜塑形镜的眼作为戴镜组,未作处理的另一眼作为未戴镜组。戴镜眼组22眼,等效球镜度-2.75±1.16D;未戴镜眼组22眼,等效球镜度-0.10±0.32D。观察戴镜前和戴镜12mo后双眼屈光度差值、单眼调节幅度、调节灵敏度和调节反应的变化情况。结果:戴镜组戴镜前的调节幅度和调节灵敏度低于未戴镜组(P<0.01),调节滞后高于未戴镜组(P<0.05)。戴镜组配戴12mo后的单眼调节幅度15.63±1.66D高于戴镜前11.25±3.15D(t=3.63,P<0.01),与未戴镜组无差异(t=0.75,P=0.46)。戴镜组配戴12mo后的单眼调节灵敏度14.63±1.58cyc/min高于戴镜前9.25±3.38cyc/min(t=2.83,P=0.01),与未戴镜组无差异(t=0.38,P=0.71)。戴镜组配戴12mo后的调节滞后0.62±0.29D较戴镜前1.35±0.26D减少(t=2.57,P=0.02),与未戴镜组无差异(t=0.61,P=0.55)。戴镜12mo后,未戴镜组的平均屈光度为-0.75±0.35D,戴镜组屈光度增长了-0.15±0.22D(t=2.90,P<0.01),未戴镜组屈光度增长了-0.65±0.39D(t=4.24,P<0.01),两组间屈光度的变化差值有差异(t=5.30,P<0.01)。未戴镜组12mo前后调节功能的变化无差异(P>0.05)。结论:屈光参差儿童单眼配戴角膜塑形镜后戴镜眼的调节功能较戴镜前明显改善,且与对侧眼一致,戴镜眼的屈光状态更稳定,未戴镜眼逐渐呈现轻度近视屈光状态,但调节功能未出现明显变化。 展开更多
关键词 屈光参差 角膜塑形镜 调节 单眼 近视控制
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Multicenter case-control study of the risk factors for ulcerative colitis in China 被引量:25
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作者 Yu-Fang Wang Qin Ou-yang +16 位作者 Bing Xia li-na liu Fang Gu Kai-Fang Zhou Qiao Mei Rui-Hua Shi Zhi-Hua Ran Xiao-Di Wang Pin-Jin Hu Kai-Chun Wu Xin-Guang liu Ying-Lei Miao Ying Han Xiao-Ping Wu Guo-Bing He Jie Zhong Guan-Jian liu 《World Journal of Gastroenterology》 SCIE CAS 2013年第11期1827-1833,共7页
AIM:To evaluate potential risk factors in the development of ulcerative colitis(UC) in China.METHODS:A total of 1308 patients with UC and 1308 age-matched and sex-matched controls were prospectively studied in China.T... AIM:To evaluate potential risk factors in the development of ulcerative colitis(UC) in China.METHODS:A total of 1308 patients with UC and 1308 age-matched and sex-matched controls were prospectively studied in China.The UC cases were collected from 17 hospitals in China from April 2007 to April 2010.Uniform questionnaires were designed to investigate risk factors including smoking,appendectomy,stress,socio-economic conditions,nonsteroidal antiinflammatory drugs(NSAIDs),oral contraceptives,diet,breastfeeding,infections and family sanitary conditions.Group comparisons by each factor were done using simple logistic regression analysis.Conditional logistic regression was used for multivariate analysis.RESULTS:By univariate analysis,the variables predictive of UC included feeling stress,light and heavy alcoholic drinking,spicy food,sugar consumption and infectious diarrhea,while heavy tea intake and tap water consumption were protective against UC.On multivariate analysis,the protective factor for UC was tap water consumption [odds ratios(OR) = 0.424,95%CI:0.302-0.594,P < 0.001];while the potential risk factors for UC were heavy sugar consumption(OR = 1.632,95%CI:1.156-2.305,P < 0.001),spicy food(light intake:OR = 3.329,95%CI:2.282-4.857,P < 0.001;heavy intake:OR = 3.979,95%CI:2.700-5.863,P < 0.001),and often feeling stress(OR = 1.981,95%CI:1.447-2.711,P < 0.001).Other factors,such as smoking habit,appendectomy,breastfeeding,a history of measles,rural or urban residence,education,oral contraceptives,and NSAID use have not been found to have a significant association with the development of UC in the present study.CONCLUSION:Our study showed tap water consumption was a protective factor for UC,while spicy food,heavy sugar consumption and often feeling stress were risk factors for UC in this Chinese population. 展开更多
关键词 ULCERATIVE COLITIS Risk factors CASE-CONTROL study
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Complete mitochondrial genome of yellow meal worm (Tenebrio molitor) 被引量:4
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作者 li-na liu Cheng-Ye WANG 《Zoological Research》 CAS CSCD 北大核心 2014年第6期537-545,共9页
The yellow meal worm (Tenebrio molitor L.) is an important resource insect typically used as animal feed additive. It is also widely used for biological research. The first complete mitochondrial genome of T. rnolit... The yellow meal worm (Tenebrio molitor L.) is an important resource insect typically used as animal feed additive. It is also widely used for biological research. The first complete mitochondrial genome of T. rnolitor was determined for the first time by long PCR and conserved primer walking approaches. The results showed that the entire mitogenome of T. molitor was 15 785 bp long, with 72.35% A+T content [deposited in GenBank with accession number KF418153]. The gene order and orientation were the same as the most common type suggested as ancestral for insects. Two protein-coding genes used atypical start codons (CTA in ND2 and AAT in COX1), and the remaining 11 protein-coding genes started with a typical insect initiation codon ATN. All tRNAs showed standard clover-leaf structure, except for tRNASer (AGN), which lacked a dihydrouridine (DHU) arm. The newly added T. molitor mitogenome could provide information for future studies on yellow meal worm. 展开更多
关键词 TENEBRIONIDAE MITOGENOME EVOLUTION Resource insect Yellow meal worm
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CHARACTERIZING FLUORESCENCE LIFETIME OF NAD(P)H IN HUMAN LEUKEMIC MYELOID CELLS AND MONONUCLEAR CELLS
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作者 LI-SHENG LIN li-na liu +3 位作者 HUI-FANG HUANG YUAN-ZHONG CHEN BU-HONG LI ZHENG HUANG 《Journal of Innovative Optical Health Sciences》 SCIE EI CAS 2013年第4期56-62,共7页
The aim of this er vito study was to explore the potential of using the fluorescence lifetime of intraellular reduced nicotinamide adenine dinucleotide(phosphate)(NAD(P)H)as a label-free indicator to characterize the ... The aim of this er vito study was to explore the potential of using the fluorescence lifetime of intraellular reduced nicotinamide adenine dinucleotide(phosphate)(NAD(P)H)as a label-free indicator to characterize the di ferencs between human leukemic myeloid cells and normal mononuclear cells(MNC).The steady-state and time-resolved autofuorescence of two human leukemic myeloid cell lines(K562,HL60)and MNC were measured by a spectrofuorimeter.According to excitation-enmission matrix(EEM)analysis,the optimal emission of NAD(P)H in these cells suspensions occurred at 445 nm.Furthermore,the fuorescence lifetimes of NAD(P)H in leukemic myeloid cells and MNC were determined by fitting the time-resolved autofuorescence data.The mean fuorescence lifetimes of NAD(P)H in K562,HL60,and MNC cells were 557±1.19,4.45±0.71,and 7.31±0.60 ns,respectively.There was a significant diference in the mean lifetime of NAD(P)H between leukemic myeloid cells and MNC(p<0.05).The difference was essentally caused by the change in relative concentration of free and protein-bound NAD(P)H.This study suggests that the mean fuorescence lifetime of NAD(P)H might be a potential label-free indicator for differentiating leukemic myeloid cells from MNC. 展开更多
关键词 Leukemic myeloid cells normal mononucear cells AUTOFLUORESCENCE nicotinarmide adenine dimucleotide lifet ime DIFFERENTIATION
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Evaluation of hepatic fibrosis parameter model and elastic modulus of liver and spleen for the diagnosis of hepatic fibrosis in chronic hepatitis b
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作者 Wei-Ting Lu Yi-Yun Wu +2 位作者 Hai-Yan Guo li-na liu Jian-Xue Zhao 《Journal of Hainan Medical University》 2020年第9期24-27,共4页
Objective Toinvestigate the diagnostic value of hepatic fibrosis parameter model and elastic modulus of liver and spleen in hepatic fibrosis of chronic hepatitis b.Methods 77 patients with hepatic fibrosis of chronic ... Objective Toinvestigate the diagnostic value of hepatic fibrosis parameter model and elastic modulus of liver and spleen in hepatic fibrosis of chronic hepatitis b.Methods 77 patients with hepatic fibrosis of chronic hepatitis in the infection clinic were recruited from July 2016 to December 2018.According to the classification of hepatic fibrosis,23 patients were classified as S1,20 as S2,18 as S3 and 16 as S4.The serum indexes of liver function in all patients were tested,FIB-4,APRI and GPR model indexes were calculated.SWE values of liver and spleen were evaluated,and the correlation between FIB-4,APRI,GPR and SWE was analyzed.Results The SWE values of liver and spleen in the study group were significantly higher than those in the normal group(P<0.01),and the differences in serum GGT,PLT,AST and portal vein velocity between the two groups were statistically significant(P<0.01).GGT and PLT were correlated with SWE values of liver and spleen,which were statistically significant(P<0.01).The model indexes of fib-4,APRI and GPR in the study group were all higher than those in the normal group,with statistically significant differences(P<0.01).Pearson correlation analysis showed that liver SWE value and spleen SWE value were positively correlated with fib-4,APRI and GPR,and the differences were significant(P<0.01),with a higher correlation with GPR.Conclusion GGT,PLT and GPR are positively correlated with SWE of liver and spleen,and combined detection can improve the early diagnosis accuracy of liver fibrosis. 展开更多
关键词 Liver fibrosis parameter model ELASTOGRAPHY Chronic hepatitis b Hepatic fibrosis The diagnosis
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Effect of pelvic floor rehabilitation technique in preventing the postpartum pelvic floor dysfunction
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作者 Shi-Qiong Li li-na liu +1 位作者 Qing Gou Xiao-Zhi Zhang 《Journal of Hainan Medical University》 2017年第4期129-132,共4页
Objective:To explore the effect of pelvic floor rehabilitation technique in preventing the postpartum pelvic floor dysfunction and on the sexual life quality.Methods:A total of 286 puerpera with pelvic floor dysfuncti... Objective:To explore the effect of pelvic floor rehabilitation technique in preventing the postpartum pelvic floor dysfunction and on the sexual life quality.Methods:A total of 286 puerpera with pelvic floor dysfunction who were admitted in our hospital from May, 2014 to May, 201542 d after delivery were included in the study, and randomized into the treatment group and the control group with 143 cases in each group. After guidance, the puerpera in the control group were given pelvic floor muscle training by themselves at home. On this basis, the puerpera in the treatment group were treated by the pelvic floor rehabilitation apparatus. The puerpera in the two groups were treated for 4 weeks. The pelvic floor function before treatment, 6 months and 1 year after delivery was detected. The color Doppler ultrasound apparatus was used to detect BSD, PUVA, UVJ-M, and BND 3 months after delivery.Results:BND, PUVA-R, PUVA-S, and UVJ-M 3 months after delivery in the treatment groups were significantly lower than those in the control group, while BSD-S was significantly higher than that in the control group. The improvement of type I and Ⅱ muscle fiber fatigue (%), POP-Q degree, AP indication point (cm), and vaginal dynamic pressure (cmH2O) was significantly superior to that in the control group. The comparison of pelvic floor muscle strength classification before treatment between the two groups was not statistically significant. After treatment, the pelvic floor muscle in the two groups was significantly strengthened, and the proportion of V grade patients was significantly increased when compared with before treatment.Conclusions: The postpartum early pelvic floor rehabilitation technique can effectively enhance the pelvic floor function, and prevent the postpartum pelvic floor dysfunction, with an accurate efficacy;therefore, it deserves to be widely recommended in the clinic. 展开更多
关键词 PELVIC FLOOR REHABILITATION TECHNIQUE PELVIC FLOOR DYSFUNCTION PELVIC FLOOR function
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Microstructure and Properties of 7075Al Alloy Fabricated by Directly Combined of Spray Forming and Continuous Extrusion Forming under Different Atomization Gas Pressures 被引量:3
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作者 Ye-Gao Chen Yi Zhong +4 位作者 Jiang-Cheng Yin Li-Qiang Wang li-na liu Huan Yang Ying-Li liu 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2016年第9期804-812,共9页
A new process consisting of the spray forming and the continuous extrusion forming for manufacturing 7075A1 alloy was proposed. The microstructure evolution, mechanical properties and the resistance to stress corrosio... A new process consisting of the spray forming and the continuous extrusion forming for manufacturing 7075A1 alloy was proposed. The microstructure evolution, mechanical properties and the resistance to stress corrosion cracking of the alloy were studied. The results indicate that the spray forming process induces obviously grain refinement and greatly lower segregation microstructure. Besides, the Conform process produces finer grains and conduces to more uniform distribution of the precipitates of A1Cu and MgZn2 phases. The fabricated alloy shows good comprehensive mechanical properties and superb performance of stress corrosion resistance. Moreover, a better combination of the mechanical properties and the resistance to stress corrosion cracking could then be obtained under a certain condition of atomization gas pressure of 0.19 MPa. The enhanced properties are attributed to the following factors, which include the grain refinement, the fine and homogeneous distribution of A1Cu and MgZn2 phases, the high density of the extruded products, as well as the discontinuous distribution of the grain boundaries after retrogression and reaging (RRA) heat treatment. 展开更多
关键词 7075A1 alloy Spray forming Continuous extrusion forming MICROSTRUCTURE PROPERTY
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Epidemiologically characteristics of human brucellosis and antimicrobial susceptibility pattern of Brucella melitensis in Hinggan League of the Inner Mongolia Autonomous Region,China 被引量:3
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作者 Hai-Tao Yuan Cheng-Ling Wang +4 位作者 li-na liu Dan Wang Dan Li Zhen-Jun Li Zhi-Guo liu 《Infectious Diseases of Poverty》 SCIE 2020年第3期146-147,共2页
Background:Hinggan League is located in the Northeast of the Inner Mongolia Autonomous Region,the historically endemic area of animal and human brucellosis.In this study,the epidemiological characteristics of human br... Background:Hinggan League is located in the Northeast of the Inner Mongolia Autonomous Region,the historically endemic area of animal and human brucellosis.In this study,the epidemiological characteristics of human brucellosis were analyzed,and the genotypic profile and antimicrobial susceptibilities of Brucella melitensis strains isolated from humans in Hinggan League were investigated.Methods:The epidemic characteristics were described using case number,constituent ratio,and rate.The 418 human blood samples were collected and tested by bacteriology,and suspect colonies were isolated and identified by conventional biotyping assays,the VITEK 2.0 microbial identification system,and AMOS(Brucella abortus,B.melitensis,B.ovis,and B.suis)-PCR.Subsequently,all strains were genotyped using multiple-locus variable-number tandem repeat analysis(MLVA)assays,and the antimicrobial susceptibility pattern of Brucella strains against the 10 most commonly used antibiotics was determined by microdilution method.Results:A total of 22848 cases of human brucellosis were reported from 2004 to 2019,with an annual average incidence of 87.2/100000.The incidence rates in developed areas of animal husbandry(Horqin Youyi Qianqi[161.2/100000]and Horqin Youyi Zhongqi[112.1/100000])were significantly higher than those in forest areas(Arxan[19.2/100000])(χ2=32.561,P<0.001).In addition,peak morbidity occurred during May–August,accounting for 72.6%(16582/22848)of cases.The highest number of cases occurred in the 40+age group,accounting for 44.4%(10137/22484)of cases,and morbidity in males was significantly higher than that in females in all age groups(χ2=299.97,P<0.001),the most common occupation was farmers.A total of 54 B.melitensis strains were divided into 37 genotypes(GT1–37)with 80–100%genetic similarity.All 25 strains were sensitive to seven tested antibiotics,phenotypic resistance to cotrimoxazole and azithromycin was observed in 5(20%)and 25(100%)of the isolates,respectively.Conclusions:Human brucellosis exhibited a significant increasing trend and B.melitensis is the main pathogen responsible for human brucellosis in this region.Improved surveillance of infected animals(sheep)and limiting their transfer and trade are optional strategies for decreasing the incidence of this disease. 展开更多
关键词 BRUCELLOSIS Epidemiology characteristic Brucella melitensis GENOTYPING Antimicrobial susceptibility Hinggan league Inner Mongolia Autonomous Region
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Tuning Acceptor Length in Photocatalytic Donor-Acceptor Conjugated Polymers for Efficient Solar-to-Hydrogen Energy Conversion 被引量:2
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作者 Qian Li Jia Li +6 位作者 Wen-Rui Wang li-na liu Zi-Wen Xu Guanghui Xie Jingjing Li Jianhua Yao Wei-Shi Li 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2022年第20期2457-2467,共11页
The development of conjugated polymer photocatalysts for efficient solar-to-hydrogen energy conversion is highly desirable for the sustainability of our society.Although the construction of donor-acceptor(D-A)structur... The development of conjugated polymer photocatalysts for efficient solar-to-hydrogen energy conversion is highly desirable for the sustainability of our society.Although the construction of donor-acceptor(D-A)structure in conjugated polymer photocatalysts for solar-to-hydrogen energy conversion has been well documented,less attention has been paid on how large D and how large A units combined together could achieve the best performance.Herein,a series of D-A copolymers P(BDT-DBTSOx)(x=7,19,39,and 79)composed of a benzodithiophene(BDT)donor unit and an oligomeric dibenzo[b,d]thiophene sulfone(DBTSO)acceptor segment were synthesized and studied.It was found that the polymer photocatalytic stabilities under full-arc irradiation improved upon shortening the length of the acceptor segment.Under visible light irradiation and in the presence of 3 wt%Pt cocatalyst,P(BDT-DBTSO79)displayed the best performance with an optimal hydrogen evolution rate of 119.3±5.8 mmol·g^(-1)·h^(-1).This is 1.4-fold as that of DBTSO homopolymer and 22.5-fold as that of BDT/DBTSO alternative copolymer,highlighting the importance of acceptor length in D-A structure for achieving high photocatalytic performance. 展开更多
关键词 Photocatalysis Water splitting Solar-to-hydrogen energy conversion Conjugated polymers Donor-acceptor systems
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Achieving excellent temperature-stable dielectric properties of Bi_(0.5)Na_(0.5)TiO_(3)-based lead-free ceramics via doping AgNbO_(3) 被引量:1
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作者 li-na liu Xiao-ming Chen +1 位作者 Xing-xing Wang Han-li Lian 《Journal of Advanced Dielectrics》 2023年第5期34-41,共8页
The lead-free ceramics(1−x)(0.94Bi0.47Na0.47Ba0.06TiO3-0.06BiAlO3)-xAgNbO3(denoted as BNBTA-xAN)were synthesized via a solid-state sintering method.The effect of AgNbO3 doping amount on dielectric properties of the ce... The lead-free ceramics(1−x)(0.94Bi0.47Na0.47Ba0.06TiO3-0.06BiAlO3)-xAgNbO3(denoted as BNBTA-xAN)were synthesized via a solid-state sintering method.The effect of AgNbO3 doping amount on dielectric properties of the ceramics was studied systematically.X-ray diffraction(XRD),scanning electron microscope(SEM)and Raman spectroscope were used to detect the structure of the ceramics.Temperature-dependent dielectric spectra,frequency-dependent dielectric constant and alternating current(ac)electric conductance at various temperatures were measured.The doping of AgNbO3 greatly reduces dielectric constant around Curie temperature and thus enhances the temperature stability of the dielectric constant.The ceramic BNBTA-0.03AN exhibits excellent temperature-stable dielectric properties with temperature coefficient of capacitance(TCC)≤±15%between 55°C and 418°C with temperature window 363°C and small changes of dielectric constant and dielectric loss from 100 Hz to 1 MHz at different temperatures.The obtained ceramics are expected to be used in high-temperature capacitors due to its excellent temperature stability. 展开更多
关键词 Microstructure dielectric properties lead-free ceramics BNT
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Improving Both Electron and Hole Mobilities of an Ambipolar Polymer by Integrating Sodium Sulfonate-Tethered Alkyl Side Chains 被引量:1
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作者 li-na liu Yun-Peng Li +5 位作者 Maria Khalil Zi-Wen Xu Guanghui Xie Xingmin Zhang Jingjing Li Wei-Shi Li 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2020年第12期1663-1670,共8页
of main observation and conclusion High performance ambipolar organic semiconductors are highly desirable for organic logic circuits.Herein,we demonstrate the integration of sodium sulfonate(SS)-tethered sidechains in... of main observation and conclusion High performance ambipolar organic semiconductors are highly desirable for organic logic circuits.Herein,we demonstrate the integration of sodium sulfonate(SS)-tethered sidechains into a diketopyrrolopyrrole-based ambipolar polymer(PDPP3T)can simultaneously improve its hole and electron transport performances either parallel or perpendicular to polymer film.Three SS-functionalized polymers(PDPP3T-XSS,x=0.025,0.05 and 0.10)were synthesized and studied.It was found that SS functionalization can reinforce interchain n-Ti interactions,slightly lower frontier orbital energy levels,produce more rod-like structures in film,and change chain-packing from edge-on to face-on fashion,but has little influence on thermal properties.More interestingly,organic field-effect transistors reported hole mobility of 0.27±0.066 cm^2.V^-1·s^-1 and electron mobility of 0.038±0.016 cm^2.V^-1·s^-1 for PDPP3T,while increased 2.4 and 5 folds to 0.64±0.087 and 0.19±0.051 cm^2.V^-1·s^-1 for PDPP3T-0.025SS,respectively.Moreover,PDPP3T-xSS devices displayed reduced threshold voltages for both hole and electron transports.Meanwhile,space charge-limited current method found SS functionalization achieved an order of magnitude increase in electron mobility and slight enhancement in hole mobility transporting perpendicular to polymer film.In-depth investigations suggest such enhancements may originate from the joint actions of chain-stacking modulation and ionic doping effect. 展开更多
关键词 properties. effect. film.
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Effect of Soda Ash on Properties of Mold Flux and Mineralogical Structures of Flux Film
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作者 Xiu-li HAN Yi-fei ZHANG +2 位作者 Lei liu li-na liu Han ZHANG 《Journal of Iron and Steel Research International》 SCIE EI CAS CSCD 2016年第3期197-202,共6页
During continuous casting,properties of mold flux and mineralogical structures of flux film play important roles in controlling steel quality.The effect of soda ash on the physical properties and crystallization chara... During continuous casting,properties of mold flux and mineralogical structures of flux film play important roles in controlling steel quality.The effect of soda ash on the physical properties and crystallization characteristics of mold flux was investigated using process mineralogy,including polarizing microscopy,X-ray diffraction,and electron microprobe,etc.Mold flux was mainly prepared using cement clinker and industrial mineral materials under laboratory conditions,and the mineralogical structures of the flux film were systematically identified and quantitatively analyzed.The results showed that,by increasing the soda ash content from 10mass% to 18mass%,the crystallization temperature,critical cooling rate and crystallization ratio of the flux film decreased,but the crystallization ratio still reached 75% after adding soda ash,and the mineral compositions and microstructures of the flux film changed slightly.When the soda ash content exceeded 14mass%,the critical cooling rate and the crystallization ratio decreased slightly,whereas the mineral content of the flux film changed evidently,with a large amount of cuspidine precipitation and a significant decrease in the wollastonite content until it reached zero,which resulted in deterioration of the lubrication of the flux film. 展开更多
关键词 soda ash mold flux flux film crystallization property mineralogical structure
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