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Disparities in precipitation effects on PM_(2.5)mass concentrations and chemical compositions:Insights from online monitoring data in Chengdu 被引量:1
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作者 Yi Li Li Zhou +7 位作者 Hefan Liu Song Liu Miao Feng Danlin Song Qinwen Tan Hongbin Jiang Sophia Zuoqiu Fumo Yang 《Journal of Environmental Sciences》 2025年第10期421-434,共14页
Precipitation plays a pivotal role in wet deposition,significantly affecting aerosol purification.The efficacy of precipitation in removing aerosols depends on its type and the characteristics of the particulates invo... Precipitation plays a pivotal role in wet deposition,significantly affecting aerosol purification.The efficacy of precipitation in removing aerosols depends on its type and the characteristics of the particulates involved.However,further research is necessary to fully understand how precipitation impacts PM_(2.5)components.This study utilized high-temporalresolution data on PM_(2.5),its components and meteorological factors to examine varying responses influenced by precipitation intensity and duration.The findings indicate that increased rainfall intensity and duration enhance PM_(2.5)and its constituents removal efficiency.Specifically,longer precipitation periods significantly improve PM_(2.5)purification,especially with drizzle and light rain.Moreover,there is a direct correlation between preprecipitation PM_(2.5)levels and its scavenging rates,with drizzle potentially exacerbating PM_(2.5)pollution under cleaner conditions(≤35μg/m^(3)).Seasonally,the efficacy of removing PM_(2.5)components varies notably in response to drizzle and light rain.In spring,higher PM_(2.5)levels after drizzlewere primarily due to increased organic carbon concentrations favored by higher relative humidity and lower pH conditions compared to other seasons,conducive to secondary organic aerosol production.Lower wind speeds and higher temperatures further contribute to water-soluble organic carbon accumulation.Daytime and nighttime precipitation exerted differing influences on PM_(2.5)components,particularly in spring where daytime drizzle and light rain significantly increased PM_(2.5)and its constituents,notably NO_(3)-,potentially associated with phase distribution changes between gas and aerosol phases in low-temperature,high-RH conditions compared to nighttime.These results propose a dualimpact mechanism of precipitation on PM_(2.5)and provide scientific basis for designing effective control strategies. 展开更多
关键词 PRECIPITATION PM_(2.5)mass concentrations Scavenging rate Chemical components Chengdu
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Vedolizumab serum trough concentrations with and without thiopurines in ulcerative colitis: The prospective VIEWS pharmacokinetics study
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作者 Thanaboon Chaemsupaphan Aviv Pudipeddi +4 位作者 Hui-Yu Lin Sudarshan Paramsothy Viraj C Kariyawasam Melissa Kermeen Rupert W Leong 《World Journal of Gastroenterology》 SCIE CAS 2025年第2期102-112,共11页
BACKGROUND Ulcerative colitis(UC)is a chronic inflammatory condition requiring continuous treatment and monitoring.There is limited pharmacokinetic data on vedolizumab during maintenance therapy and the effect of thio... BACKGROUND Ulcerative colitis(UC)is a chronic inflammatory condition requiring continuous treatment and monitoring.There is limited pharmacokinetic data on vedolizumab during maintenance therapy and the effect of thiopurines on vedolizumab trough concentrations is unknown.AIM To investigate the exposure-response relationship of vedolizumab and the impact of thiopurine withdrawal in UC patients who have achieved sustained clinical and endoscopic remission during maintenance therapy.METHODS This is a post-hoc analysis of prospective randomized clinical trial(VIEWS)involving UC patients across 8 centers in Australia from 2018 to 2022.Patients in clinical and endoscopic remission were randomized to continue or withdraw thiopurine while receiving vedolizumab.We evaluated vedolizumab serum trough concentrations,presence of anti-vedolizumab antibodies,and clinical outcomes over 48 weeks to assess exposure-response asso-ciation and impact of thiopurine withdrawal.RESULTS There were 62 UC participants with mean age of 43.4 years and 42%were females.All participants received vedolizumab as maintenance therapy with 67.7%withdrew thiopurine.Vedolizumab serum trough concentrations remained stable over 48 weeks regardless of thiopurine use,with no anti-vedolizumab antibodies detected.Pa-tients with clinical remission had higher trough concentrations at week 48.In quartile analysis,a threshold of>11.3μg/mL was associated with sustained clinical remission,showing a sensitivity of 82.4%,specificity of 60.0%,and an area of receiver operating characteristic of 0.71(95%CI:0.49-0.93).Patients discontinuing thiopurine required higher vedolizumab concentrations for achieving remission.CONCLUSION A positive exposure-response relationship between vedolizumab trough concentrations and UC outcomes suggests that monitoring drug levels may be beneficial.While thiopurine did not influence vedolizumab levels,its with-drawal may necessitate higher vedolizumab trough concentrations to maintain remission. 展开更多
关键词 PHARMACOKINETIC Vedolizumab THIOPURINE Ulcerative colitis Trough concentration Antibody Inflammatory bowel diseases
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A high-throughput measurement of critical micelle concentrations based on absolute aggregation-caused quenching probes
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作者 Xin Ji Aun Raza +3 位作者 Jianping Qi Yi Lu Haisheng He Wei Wu 《Journal of Pharmaceutical Analysis》 2025年第3期651-653,共3页
Amphiphiles,including surfactants,have emerged as indispensable elements in materials science and pharmaceutical science,and their functions are highly relying on the critical micelle concentration(CMC)[1,2].Numerous ... Amphiphiles,including surfactants,have emerged as indispensable elements in materials science and pharmaceutical science,and their functions are highly relying on the critical micelle concentration(CMC)[1,2].Numerous fluorimetry-based probes have been developed to measure CMCs[3](Fig.S1).However,CMC measurements using these probes suffer from a time-consuming and laborious procedure and large uncertainties,primarily due to their poor photo-stabilities and highly fluctuating fluorescence backgrounds. 展开更多
关键词 high throughput measurement photo stabilities fluorescence backgrounds critical micelle concentration cmc numerous materials science critical micelle concentration fluorimetry based probes absolute aggregation caused quenching
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Changes in source contribution to particle number concentrations during the 2022 COVID-19Lockdown on southern edge of North China Plain
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作者 Zeyu Gao Nan Zhang +6 位作者 Guotao Zhang Dawei Niu Wen Yang Xinhua Wang Shengli Wang Bin Han Zhipeng Bai 《Journal of Environmental Sciences》 2025年第12期447-460,共14页
The COVID-19 lockdown was a typical example of extreme emission reduction,providing an opportunity to study the impact of lockdown measures on air pollution.Particle number concentrations(PNC)originate from direct emi... The COVID-19 lockdown was a typical example of extreme emission reduction,providing an opportunity to study the impact of lockdown measures on air pollution.Particle number concentrations(PNC)originate from direct emissions or through new particle formation events.However,their variations during the lockdown period are under investigation.This study focuses on Luohe,a city on the southern edge of the North China Plain,analyzing the changes in PNC and its sources before,during,and after the COVID-19 lockdown.From March 25^(th)to May 31^(st),2022,real-time PNC measurements were conducted using a Scanning Mobility Particle Sizer for particle size.Results showed an 11.2%decrease in PNC during the lockdown compared to pre-lockdown and a 3.6%decrease compared to post-lockdown,indicating reduced local emissions and weakened regional transportation during the lockdown.Positive Matrix Factorization analysis identified six sources contributing to the total PNC,including photochemical nucleation,aged photochemical nucleation,gasoline vehicle emissions,diesel vehicle emissions,coal and biomass combustion,and secondary aerosols.The significant changes in source emissions indicate a substantially reduced traffic volume after the implementation of lockdown measures(2644.8#/cm^(3),2202.2#/cm^(3),2792.7#/cm^(3)).Concurrently,photochemical nucleation(310.1#/cm^(3),306.3#/cm^(3),393.1#/cm^(3))and photochemical nucleation aging(592.8#/cm^(3),744.1#/cm^(3),810.7#/cm^(3))exhibited increasing trends,while coal/biomass combustion(1656.6#/cm^(3),1586.2#/cm^(3),980.0#/cm^(3))and secondary sources(999.4#/cm^(3),791.1#/cm^(3),804.1#/cm^(3))showed decreasing trends.In summary,the contributions of traffic emissions to PNC highlight the potential for targeted traffic management strategies to improve urban air quality. 展开更多
关键词 Particle number concentration Particle number size distribution Source apportionment Epidemic lockdown
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An effective approach for correlating Na^(+) concentrations with sweating rates in wearable sweat sensing platform
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作者 Anwei He Xiaohe Wang +6 位作者 Liang Zhang Haolong Zhang Xingli Xu Chenyang Yu Yongquan Ma Wei Wei Pengfei Niu 《Nanotechnology and Precision Engineering》 2025年第1期58-67,共10页
Accurately correlating the sweating rate and the concentration of biomarkers in sweat is essential in many sweat-based diagnostic applications.These two measurements are always done simultaneously in wearable sweat se... Accurately correlating the sweating rate and the concentration of biomarkers in sweat is essential in many sweat-based diagnostic applications.These two measurements are always done simultaneously in wearable sweat sensing platforms.However,concentration measurements of biomarkers are always delayed on the timeline compared with their production,whereas there is no such delay for sweating rate.Thus,a timeline mismatch exists between these two measurements.This means that the concentration vs rate correlation constructed on the basis of such measurements will deviate from the actual correlation.This study demonstrates the existence of this mismatch and explains its cause using sweat Na^(+)measurements.It also proposes an effective approach that applies a point-by-point compensation for the delay between Na+measurements and the real-time sweating rates,such that the data on the repositioned concentration vs time curve correspond to exactly the same point on the timeline as their production.A vison sensor is developed to measure the sweating rate with high accuracy at a frequency of more than 0.1 Hz.Off-body and on-body measurements of sweating rate and Na^(+)concentration are carried out,and concentration–rate correlations are constructed using both measured and repositioned concentration curves.The least squares and random forest methods are employed to fit the constructed correlations and evaluate the reliability of the proposed approach.The use of the repositioned concentration curve gives a constructed correlation that is much closer to the actual one.This study indicates the necessity to rearrange sensor-measured biomarker concentration vs time curves when correlations of concentration with sweating rate need to be constructed and proposes a practical point-by-point data repositioning strategy for doing so.The results presented here will benefit the study of sweat biomarkers with unclear correlations with sweating rate,as well as providing a basis for the development of more reliable sweat-based diagnostic methods. 展开更多
关键词 Wearable sweat monitoring Sweating rate Concentration rate correlation Timeline mismatch Machine learning
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Interpreting hourly mass concentrations of PM_(2.5)chemical components with an optimal deep-learning model
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作者 Hongyi Li Ting Yang +2 位作者 Yiming Du Yining Tan Zifa Wang 《Journal of Environmental Sciences》 2025年第5期125-139,共15页
PM_(2.5)constitutes a complex and diversemixture that significantly impacts the environment,human health,and climate change.However,existing observation and numerical simulation techniques have limitations,such as a l... PM_(2.5)constitutes a complex and diversemixture that significantly impacts the environment,human health,and climate change.However,existing observation and numerical simulation techniques have limitations,such as a lack of data,high acquisition costs,andmultiple uncertainties.These limitations hinder the acquisition of comprehensive information on PM_(2.5)chemical composition and effectively implement refined air pollution protection and control strategies.In this study,we developed an optimal deep learning model to acquire hourly mass concentrations of key PM_(2.5)chemical components without complex chemical analysis.The model was trained using a randomly partitioned multivariate dataset arranged in chronological order,including atmospheric state indicators,which previous studies did not consider.Our results showed that the correlation coefficients of key chemical components were no less than 0.96,and the root mean square errors ranged from 0.20 to 2.11μg/m^(3)for the entire process(training and testing combined).The model accurately captured the temporal characteristics of key chemical components,outperforming typical machine-learning models,previous studies,and global reanalysis datasets(such asModern-Era Retrospective analysis for Research and Applications,Version 2(MERRA-2)and Copernicus Atmosphere Monitoring Service ReAnalysis(CAMSRA)).We also quantified the feature importance using the random forest model,which showed that PM_(2.5),PM_(1),visibility,and temperature were the most influential variables for key chemical components.In conclusion,this study presents a practical approach to accurately obtain chemical composition information that can contribute to filling missing data,improved air pollution monitoring and source identification.This approach has the potential to enhance air pollution control strategies and promote public health and environmental sustainability. 展开更多
关键词 Pm2.5 chemical composition Hourly mass concentration Deep learning Bayesian optimization Feature importance
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A novel method for simultaneous measurement of^(222)Rn and^(220)Rn progeny concentrations measured by an alpha spectrometer
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作者 Zhong-Kai Fan Jia-Le Sun +5 位作者 Hao-Xuan Li Xiang-Ming Cai Hui Yang Shou-Kang Qiu Yan-Liang Tan Jian Shan 《Nuclear Science and Techniques》 2025年第1期127-139,共13页
The accumulation of^(222)Rn and^(220)Rn progeny in poorly ventilated environments poses the risk of natural radiation exposure to the public.A previous study indicated that satisfactory results in determining the^(222... The accumulation of^(222)Rn and^(220)Rn progeny in poorly ventilated environments poses the risk of natural radiation exposure to the public.A previous study indicated that satisfactory results in determining the^(222)Rn and^(220)Rn progeny concentrations by measuring the total alpha counts at five time intervals within 560 min should be expected only in the case of high progeny concentrations in air.To complete the measurement within a relatively short period and adapt it for simultaneous measurements at comparatively lower^(222)Rn and^(220)Rn progeny concentrations,a novel mathematical model was proposed based on the radioactive decay law.This model employs a nonlinear fitting method to distinguish nuclides with overlapping spectra by utilizing the alpha particle counts of non-overlapping spectra within consecutive measurement cycles to obtain the concentrations of^(222)Rn and^(220)Rn progeny in air.Several verification experiments were conducted using an alpha spectrometer.The experimental results demonstrate that the concentrations of^(222)Rn and^(220)Rn progeny calculated by the new method align more closely with the actual circumstances than those calculated by the total count method,and their relative uncertainties are all within±16%.Furthermore,the measurement time was reduced to 90 min,representing an acceleration of 84%.The improved capability of the new method in distinguishing alpha particles with similar energies emitted from ^(218)Po and^(212)Bi,both approximately 6 MeV,contributed to realizing more accurate results.The proposed method has the potential advantage of measuring relatively low concentrations of^(222)Rn and^(220)Rn progeny in air more quickly via air filtration. 展开更多
关键词 ^(222)Rn ^(220)Rn Progeny concentration Nonlinear fitting method Alpha spectrometer
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Simultaneous measurement of outlet temperature and species concentrations in a dual-swirl combustor via multi-diagnostic integration
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作者 Jie LI Wenyan SONG +7 位作者 Chaozong WANG Jing LI Zhibo CAO Jianping LI Shuang CHEN Xinhua QI An HUANG Jingwei ZHANG 《Chinese Journal of Aeronautics》 2025年第10期290-310,共21页
To provide advanced diagnostic techniques for diagnosing the outlet temperature distribution and species concentrations of future advanced combustors,this study focuses on a dual-swirl single-dome rectangular combusto... To provide advanced diagnostic techniques for diagnosing the outlet temperature distribution and species concentrations of future advanced combustors,this study focuses on a dual-swirl single-dome rectangular combustor.Through the integration of multiple diagnostics,simultaneous measurement of outlet temperature distribution and species concentrations was achieved.The study validates the engineering applicability of these simultaneous measurements using tungsten-rhenium(W-Re)thermocouples and Coherent Anti-Stokes Raman Scattering(CARS),CARS and Tunable Diode Laser Absorption Spectroscopy(TDLAS),as well as Gas Analysis(GA)and Mass Spectrometry(MS).The results demonstrate that measurements by thermocouples and CARS exhibit good consistency and repeatability,with a relative deviation of less than 4%,fully meeting the requirements of engineering experiments.The spatial distribution reconstruction results of TDLAS can reflect the temperature distribution characteristics at the combustor outlet.Temperature comparison between TDLAS and CARS at single-point positions shows consistent results,with a relative deviation of less than 11%and 7%under both conditions,respectively.Simultaneous measurements by integrating GA and MS show high engineering applicability for the first time,meeting the requirements for measuring both inorganic species and free radicals at the combustor outlet.Under C_(1)condition,the relative deviations of four key species(Unburned Hydrocarbon(UHC),NO,O_(2),and CO_(2))remain within 2%,while that of NO_(2)is slightly higher at approximately 8%.Under C_(2)condition,the overall deviations increase for most species,with only O_(2)and CO_(2)maintaining relatively low deviations.The primary species of UHCs at the combustor outlet under both conditions are small molecular hydrocarbons(C_(3)-C_(8))and RO_(2)radicals,accounting for over 90%of total UHC.Specifically,RO_(2)species(R is C_(1)-C_(2)alkyl groups)are the predominant species,accounting for 74.3%and 82.1%of total RO_(2)under both conditions,respectively.These integrated diagnostic methods for temperature and species concentrations at the combustor outlet serve as a crucial reference for its engineering applications. 展开更多
关键词 Aero-engine combustor Coherent anti-Stokes Raman scattering Gas analysis Mass spectrometry Outlet temperature Species concentrations Tunable diode laser absorption spectroscopy W-Re thermocouple
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内蒙古寒区水稻灌溉需求与降雨利用分析
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作者 张恒 纪雪晴 +5 位作者 华克骥 徐阳 胡旭铧 赵崇信 崔远来 罗玉峰 《节水灌溉》 北大核心 2026年第3期42-47,54,共7页
掌握内蒙古寒区降雨与水稻灌溉需求的关系是优化灌溉制度与高效利用水资源的重要依据。基于1959-2017年内蒙古寒区4个典型水稻站点的逐日气象数据,构建水量平衡模型,应用Mann-Kendall检验分析水量平衡要素变化趋势,结合Pearson相关系数... 掌握内蒙古寒区降雨与水稻灌溉需求的关系是优化灌溉制度与高效利用水资源的重要依据。基于1959-2017年内蒙古寒区4个典型水稻站点的逐日气象数据,构建水量平衡模型,应用Mann-Kendall检验分析水量平衡要素变化趋势,结合Pearson相关系数与最大互信息系数揭示要素间的相关性,同时采用降雨集中度、集中期揭示降雨时序特征。结果表明,内蒙古寒区水稻生育期降雨量较少(<500 mm),但作物需水量较高(>600 mm),整体表现出较大的灌溉需求:开鲁(921.1 mm)>巴林左旗(799.7 mm)>扎赉特旗(777.6 mm)>扎兰屯(669.5mm)。各站点均表现为高降雨利用率(>80%)但低降雨贡献度(<40%)的特征,有限降雨虽被高效利用,但难以满足灌溉需求。近年来内蒙古寒区降雨呈下降趋势,ETc呈现上升的趋势,灌溉依赖性持续增强。未来在降雨减少与蒸散增强的气候变化下,内蒙古寒区可结合降雨预报优化灌溉模式,以提升降雨贡献度,缓解水资源压力。 展开更多
关键词 寒区水稻 作物需水 灌溉需求 降雨利用 降雨集中度 降雨集中期 稻田水量平衡
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可溶液剂、微乳剂和可分散液剂的区别
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作者 徐勇 吴学民 《农药科学与管理》 2026年第1期45-49,共5页
近年来,可溶液剂、微乳剂和可分散液剂因在分散性、润湿性、渗透性以及生物活性方面表现优异而受到广泛关注。然而,这3种剂型在外观形态和部分性能指标上存在相似性,易导致混淆,企业在登记过程中常因剂型选择不当而导致产品登记申请被... 近年来,可溶液剂、微乳剂和可分散液剂因在分散性、润湿性、渗透性以及生物活性方面表现优异而受到广泛关注。然而,这3种剂型在外观形态和部分性能指标上存在相似性,易导致混淆,企业在登记过程中常因剂型选择不当而导致产品登记申请被驳回。本文从定义、特点、组分构成、理化性质及质量控制等方面对3种剂型进行分析,旨在加深从业人员对3种剂型的理解,提高农药产品登记效率。 展开更多
关键词 可溶液剂 微乳剂 可分散液剂 剂型对比 产品登记
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真空浓缩处理对黑果腺肋花楸花色苷的影响
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作者 陶冬冰 张旋 +3 位作者 张琦 潘松 安悦嘉 马凤鸣 《食品研究与开发》 2026年第5期77-86,共10页
真空浓缩是花色苷制备中的关键工艺,也是制备工艺中易导致花色苷热损伤的主要工艺,不适当的真空浓缩易引起花色苷热损伤,导致花色苷品质下降。因此,该文以黑果腺肋花楸花色苷为处理对象,分析浓缩温度和浓缩真空度关键工艺参数对花色苷... 真空浓缩是花色苷制备中的关键工艺,也是制备工艺中易导致花色苷热损伤的主要工艺,不适当的真空浓缩易引起花色苷热损伤,导致花色苷品质下降。因此,该文以黑果腺肋花楸花色苷为处理对象,分析浓缩温度和浓缩真空度关键工艺参数对花色苷含量、抗氧化活性、色泽和结构表征的影响。结果表明,低浓缩真空度以及浓缩温度虽能更好地保持花色苷含量,但浓缩效率过低;真空条件下花色苷降解反应符合零级和一级降解动力学模型;浓缩温度60℃、浓缩真空度0.075 MPa为黑果腺肋花楸花色苷最适真空浓缩工艺条件。在此条件下,浓缩处理70 min,花色苷含量降低26.21%,DPPH自由基和羟自由基清除率分别降低15.45%和13.81%,且未对花色苷主体结构产生明显影响。 展开更多
关键词 真空浓缩 花色苷 黑果腺肋花楸 抗氧化 结构
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氧空位调控氧化钨薄膜的设计制备及其氢敏变色性能研究
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作者 王宁 田佳蔚 +1 位作者 孙樱溪 谭秋林 《功能材料》 北大核心 2026年第2期174-179,共6页
以WO_(3)为基础的氢敏变色型传感器无需额外供电便可以通过肉眼观察直接判断是否发生氢气泄露,在可穿戴氢安全标识、氢气管道输送等领域具有及时便捷、低成本的独特优势。然而WO_(3)的氢敏变色机理及氧空位的影响作用等还不明晰,这制约... 以WO_(3)为基础的氢敏变色型传感器无需额外供电便可以通过肉眼观察直接判断是否发生氢气泄露,在可穿戴氢安全标识、氢气管道输送等领域具有及时便捷、低成本的独特优势。然而WO_(3)的氢敏变色机理及氧空位的影响作用等还不明晰,这制约了WO_(3)基氢敏变色型传感器的性能提升和推广应用。为此,本项目采用反应磁控溅射技术设计制备了氧空位浓度可调的WO_(3)薄膜,研究了薄膜成分、颜色、元素价态和氧空位浓度等与溅射气氛中氧气浓度的关系。探索了不同Pd/WO_(3)薄膜对氢气的颜色响应,发现增加WO_(3)薄膜中氧空位浓度可以提高薄膜氢敏变色的灵敏度,但WO_(3)薄膜中氧含量过低时,W5+和金属态钨的存在会使薄膜本身具有较深的颜色,氢敏变色特性消失。反应磁控溅射制备的高氧空位非晶态Pd/WO_(3)薄膜最佳工作温度为200℃,15 s左右1%浓度氢气可以引起薄膜102.4的明显色差变化,氢敏变色效果明显。 展开更多
关键词 WO_(3)薄膜 氧空位浓度 气致变色 氢气传感器
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文拉法辛血药浓度超警戒值风险预测模型的临床价值研究
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作者 张彦景 周春华 +3 位作者 李晓东 刘琰 王婧 于静 《中国全科医学》 北大核心 2026年第6期777-782,共6页
背景文拉法辛为5-羟色胺肾上腺素再摄取抑制剂(SNRI)类抗抑郁药,广泛用于治疗重度抑郁、广泛性焦虑障碍和抑郁共病,《中国精神科治疗药物监测临床应用专家共识(2022年版)》提出在治疗过程中,文拉法辛可行血药浓度监测,避免超警戒浓度使... 背景文拉法辛为5-羟色胺肾上腺素再摄取抑制剂(SNRI)类抗抑郁药,广泛用于治疗重度抑郁、广泛性焦虑障碍和抑郁共病,《中国精神科治疗药物监测临床应用专家共识(2022年版)》提出在治疗过程中,文拉法辛可行血药浓度监测,避免超警戒浓度使用而导致不良反应发生或治疗效果不理想。但患者生理、基因多态性等因素对其血药浓度超警戒值的影响存在一定争议。目的探索抑郁患者文拉法辛血药浓度超警戒值的影响因素,并构建文拉法辛血药浓度超警戒值的风险预测模型,为文拉法辛个体化用药提供参考。方法回顾性分析2021年1月—2024年8月于河北医科大学第一医院服用文拉法辛进行治疗并接受血药浓度监测住院患者的临床资料,将所纳入患者按文拉法辛血药浓度监测值分为达标组(血药浓度100~400 ng/mL)和超警戒组(血药浓度>800 ng/mL),收集两组患者的性别、年龄、BMI、日均服药剂量、血浆白蛋白、合并用药、肝肾功能情况,采用多因素Logistic回归分析筛选文拉法辛血药浓度超警戒值的独立影响因素,根据筛选出的独立影响因素构建列线图预测模型,并对该模型进行验证。结果本研究共纳入患者590例,其中男203例(34.4%)、女387例(65.6%),平均年龄(51.9±16.4)岁。590例患者中达标组516例(87.5%)、超警戒组74例(12.5%)。多因素Logistic回归分析结果显示,日均服药剂量≥225 mg(OR=26.628,95%CI=12.912~54.916,P<0.001)、肾损害(OR=2.429,95%CI=1.215~4.854,P=0.012)、合用细胞色素P450(CYP)2D6抑制剂(OR=5.232,95%CI=2.781~9.844,P<0.001)是文拉法辛血药浓度超出警戒值的危险因素。根据所筛选出的独立影响因素,建立了文拉法辛血药浓度超警戒值的列线图预测模型,该模型预测抑郁患者文拉法辛血药浓度超警戒值的ROC曲线下面积(AUC)为0.899(95%CI=0.864~0.935),灵敏度为48.65%,特异度为95.74%,阳性预测值为62.07%,阴性预测值为92.86%;Bootstrap法验证结果显示,校正曲线与实际曲线一致性良好(Brier评分=0.072);Hosmer-Lemeshow检验结果显示,列线图预测模型的校准度良好(χ^(2)=3.160,P=0.531);临床决策曲线分析(DCA)结果显示,当阈值为0.05~0.80时,列线图模型具有较好的临床实用性。结论日均服药剂量≥225 mg、存在肾损害、合并使用CYP2D6抑制剂是抑郁患者血药浓度超警戒值的独立危险因素,据此构建的列线图模型能有效预测抑郁患者文拉法辛血药浓度超警戒风险程度,具有较高的临床应用价值。 展开更多
关键词 文拉法辛 血药浓度 治疗药物监测 影响因素 列线图 预测 超警戒值
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醇胺溶液CO_(2)吸收过程反应机制
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作者 滕卫卫 吴燕 +5 位作者 樊玉新 廖涛 王梓丞 于徽 李梦 许孝玲 《煤田地质与勘探》 北大核心 2026年第1期71-79,共9页
【目的】当前醇胺法CO_(2)捕集存在能耗与成本较高的缺点,解决这一问题的主要方法是协同不同类型醇胺的吸收、解吸优势构建复合胺溶液。羟乙基乙二胺(AEEA)和N-甲基二乙醇胺(MDEA)是2种常用主吸收剂,其调配需要准确掌握CO_(2)吸收规律,... 【目的】当前醇胺法CO_(2)捕集存在能耗与成本较高的缺点,解决这一问题的主要方法是协同不同类型醇胺的吸收、解吸优势构建复合胺溶液。羟乙基乙二胺(AEEA)和N-甲基二乙醇胺(MDEA)是2种常用主吸收剂,其调配需要准确掌握CO_(2)吸收规律,包括CO_(2)负载量、产物离子浓度分布规律、反应级数等。目前对其吸收规律认识尚不足,相关反应参数缺乏,限制了工艺模型预测准确性。【方法】研究AEEA和MDEA溶液CO_(2)吸收过程,厘清其反应机理,并基于pH值法构建产物离子浓度分布模型,回归2种胺液的反应级数,确定反应速率模型。【结果和结论】同一浓度AEEA溶液吸收容量和吸收速率均高于MDEA溶液。AEEA溶液CO_(2)吸收过程呈现出两阶段特征,接近于二级反应。AEEA与CO_(2)反应生成两性中间离子(R1R2NH+COO-)是吸收过程的初始控制步骤,而其吸收后期为传质-反应共同控制阶段。MDEA溶液CO_(2)吸收过程是碱催化水合过程,反应速率与MDEA浓度线性相关,为一级反应。基于所得新认识和模型,为碳捕集工艺中溶剂浓度、溶剂停留时间,溶剂循环量、塔器设计优化等提供理论指导。 展开更多
关键词 CO_(2)捕集 AEEA MDEA 离子浓度 反应级数
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表面处理含盐混凝土的氯离子扩散试验与模拟
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作者 周欣竹 蔡泽甬 +2 位作者 荣华 郑建军 邵海鑫 《浙江工业大学学报》 北大核心 2026年第1期30-36,共7页
表面处理是提高混凝土抗氯离子侵入阻力的重要措施。深入研究表面处理混凝土的传输特性,对于表面处理在实际工程中的应用与推广尤为重要。采用试验与数值模拟相结合的方法,探究了表面处理含盐混凝土的氯离子扩散特性。针对普通混凝土、... 表面处理是提高混凝土抗氯离子侵入阻力的重要措施。深入研究表面处理混凝土的传输特性,对于表面处理在实际工程中的应用与推广尤为重要。采用试验与数值模拟相结合的方法,探究了表面处理含盐混凝土的氯离子扩散特性。针对普通混凝土、表面涂层混凝土和表面复合涂层混凝土,利用NEL法测定了表面处理层和基底混凝土的氯离子扩散系数,并简要分析了表面涂层类型和水胶比对氯离子扩散系数的影响。将3种混凝土试件分别在盐溶液中浸泡45,90,135 d后,测定其氯离子分布,进而分析表面涂层类型、水胶比和初始含盐量对氯离子质量分数的影响。在此基础上,提出了考虑表面处理层性能退化的混凝土氯离子质量分数计算的差分法。与实测数据对比验证结果表明:该有限差分法具有较高的计算精度,可以应用于表面处理混凝土结构的使用寿命估算。 展开更多
关键词 表面处理混凝土 氯离子质量分数 浸泡试验 有限差分法
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CCCS与ECCS树脂对Au(Ⅲ)吸附性能的比较 被引量:7
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作者 党明岩 张廷安 +1 位作者 王娉 蒋孝丽 《东北大学学报(自然科学版)》 EI CAS CSCD 北大核心 2005年第11期1103-1106,共4页
分别以环硫氯丙烷和环氧氯丙烷作为交联剂,合成交联壳聚糖树脂,测定其对Au(Ⅲ)的静态吸附性能.采用正交试验法全面考察了环硫氯丙烷交联壳聚糖(CCCS)树脂和环氧氯丙烷交联壳聚糖(ECCS)树脂吸附Au(Ⅲ)过程中,各主要因素对吸附性能的影响... 分别以环硫氯丙烷和环氧氯丙烷作为交联剂,合成交联壳聚糖树脂,测定其对Au(Ⅲ)的静态吸附性能.采用正交试验法全面考察了环硫氯丙烷交联壳聚糖(CCCS)树脂和环氧氯丙烷交联壳聚糖(ECCS)树脂吸附Au(Ⅲ)过程中,各主要因素对吸附性能的影响.结果表明,环硫氯丙烷交联壳聚糖树脂比环氧氯丙烷交联壳聚糖树脂所能适应的pH值、温度、初始离子浓度等条件范围更广,且在同样吸附条件下,环硫氯丙烷交联壳聚糖树脂比环氧氯丙烷交联壳聚糖树脂有更优良的吸附性能.环硫氯丙烷交联壳聚糖树脂对Au(Ⅲ)的吸附量可达296.67μg/mg,吸附率可达98.1%. 展开更多
关键词 壳聚糖 吸附 cccs(环硫氯丙烷交联壳聚糖) ECCS(环氧氯丙烷交联壳聚糖)
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免疫程序调整前深圳市社区人群百日咳抗体水平横断面调查
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作者 段利娜 袁梦 +2 位作者 赖植发 王颖 许玉成 《热带医学杂志》 2026年第1期126-129,共4页
目的调查深圳市2023年社区人群百日咳抗体水平,评价人群百日咳免疫状况,为持续优化百日咳防控策略提供依据。方法应用多阶段分层抽样法,在深圳市若干社区选择参与者,采集2312份血清样本,使用酶联免疫吸附试验检测百日咳毒素IgG抗体(PT-I... 目的调查深圳市2023年社区人群百日咳抗体水平,评价人群百日咳免疫状况,为持续优化百日咳防控策略提供依据。方法应用多阶段分层抽样法,在深圳市若干社区选择参与者,采集2312份血清样本,使用酶联免疫吸附试验检测百日咳毒素IgG抗体(PT-IgG)。分析不同区域、性别、年龄组之间抗体浓度和阳性率差异。结果采集2312名参与者血清,其中男1080名,女1232名,福田区1368名,南山区944名。人群PT-IgG几何平均浓度(GMC)为9.84 IU/mL,2~<4岁组GMC水平最高为18.74 IU/mL,13~<16岁组最低为5.71 IU/mL。百日咳抗体总阳性率(≥100 IU/mL)为2.20%,浓度低于检出限值(<5 IU/mL)个案占31.49%。福田区和南山区人群抗体GMC水平分别为7.85和13.63 IU/mL,差异有统计学意义(U=476420.500,P<0.001),不同年龄组抗体GMC和阳性率差异均有统计学意义(H=59.907,χ^(2)=82.830,P均<0.001)。结论深圳社区人群的百日咳抗体GMC总体水平较低,儿童青少年感染风险增加,建议加强病例对照研究,以科学评价免疫策略改变的效果,提升百日咳防控水平。 展开更多
关键词 百日咳 百日咳毒素IgG抗体 几何平均浓度
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超浓缩电火花线切割加工液的研制与应用
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作者 潘传艺 谭超武 +6 位作者 谭凯元 李红庆 黎健凤 潘春阳 胡升 罗洪盛 谢珍茗 《模具制造》 2026年第3期31-32,共2页
分析了高速往复走丝电火花线切割工作介质的性能要求,阐述了快走丝电火花线切割加工液的加工性能的影响因素,通过筛选材料进行调配,成功研制出了一种超浓缩电火花线切割加工液,并在两种不同线切割机床上进行实机测试,试验表明其满足电... 分析了高速往复走丝电火花线切割工作介质的性能要求,阐述了快走丝电火花线切割加工液的加工性能的影响因素,通过筛选材料进行调配,成功研制出了一种超浓缩电火花线切割加工液,并在两种不同线切割机床上进行实机测试,试验表明其满足电火花线切割加工要求,兑水比例高达1∶40以上,综合性价比高。 展开更多
关键词 线切割加工液 超浓缩液 防锈
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液相色谱串联质谱法测定人血浆中巴洛沙韦酸浓度
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作者 何文娟 崔文彦 +4 位作者 安雪松 张心慧 李梦豪 李德强 刘秀菊 《中国药业》 2026年第3期76-80,共5页
目的建立测定人血浆中巴洛沙韦酸浓度的液相色谱串联质谱(LC-MS/MS)法。方法血浆样品经甲醇沉淀蛋白后,以度鲁特韦为内标。色谱柱为Phenomenex Luna■-C_(8)柱(50 mm×2.1 mm,3μm),流动相为甲醇-0.1%甲酸水溶液(梯度洗脱),流速为0.... 目的建立测定人血浆中巴洛沙韦酸浓度的液相色谱串联质谱(LC-MS/MS)法。方法血浆样品经甲醇沉淀蛋白后,以度鲁特韦为内标。色谱柱为Phenomenex Luna■-C_(8)柱(50 mm×2.1 mm,3μm),流动相为甲醇-0.1%甲酸水溶液(梯度洗脱),流速为0.35 mL/min,柱温为25℃,进样量为10μL,采用电喷雾电离离子源,正离子模式下进行多反应监测,用于分析的离子对质荷比(m/z)分别为484.20→247.20(巴洛沙韦酸)、420.00→277.10(度鲁特韦)。结果巴洛沙韦酸的质量浓度在0.50~80.00 ng/mL范围内与待测物和内标峰面积比值的线性关系良好(r=0.9993,n=8),定量下限为0.50 ng/mL,日内、日间精密度的RSD分别为3.27%~5.87%(n=3)、0.62%~9.12%(n=3),稳定性试验的RSD均小于5%,提取回收率为89.90%~96.94%,基质效应为100.76%~115.00%。结论该方法操作简便、专属性强、准确度高、稳定性好,可用于测定人血浆中巴洛沙韦酸的浓度。 展开更多
关键词 液相色谱串联质谱法 巴洛沙韦酸 血药浓度
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采动影响下逆断层稳定性及覆岩移动规律研究
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作者 郭文兵 胡超群 +1 位作者 张伊辉 葛志博 《河南理工大学学报(自然科学版)》 北大核心 2026年第2期1-10,共10页
目的为了深入探究采动影响下逆断层稳定性和覆岩移动规律,避免断层受采动影响发生活化失稳,开展采动影响下逆断层稳定性和覆岩移动规律研究。方法系统剖析采动影响下断层活化机制,量化评估逆断层上下盘不同开采条件下断层活化难易程度,... 目的为了深入探究采动影响下逆断层稳定性和覆岩移动规律,避免断层受采动影响发生活化失稳,开展采动影响下逆断层稳定性和覆岩移动规律研究。方法系统剖析采动影响下断层活化机制,量化评估逆断层上下盘不同开采条件下断层活化难易程度,对比分析相应覆岩破坏方式和裂隙发育规律。结果结果表明:(1)在逆断层上盘开采时,覆岩节理法向和剪切位移矢量均趋于0,表明采动对覆岩移动和断层活化未产生显著影响,断层在开采影响下出现应力集中现象,但并未发生滑移;(2)在逆断层下盘开采时,覆岩沉降最大值比上盘覆岩沉降最大值高0.16 m,且裂隙发育高度更高,覆岩节理法向和剪切位移矢量分别为0.4,1.3 m,断层在采动影响下出现应力集中和“活化”滑移失稳现象;(3)利用活化风险指数Q判断断层活化风险大小,对比上下盘开采情况发现,下盘开采后断层更易发生“活化”滑移;(4)上下盘工作面开采时,断层稳定需分别满足T/F>0.087,T/F>11.43,因此下盘开采时断层更易失稳;(5)上下盘工作面开采时,断层稳定性差异显著,在下盘工作面开采时,工作面右侧与断层的水平距离需大于117 m。结论研究结果对回收煤炭资源和保障井上下安全具有重要意义。 展开更多
关键词 逆断层 开采扰动 活化 裂隙发育 应力集中
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