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Exploring catalyst developments in heterogeneous CO_(2) hydrogenation to methanol and ethanol:A journey through reaction pathways 被引量:1
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作者 Rasoul Salami Yimin Zeng +2 位作者 xue han Sohrab Rohani Ying Zheng 《Journal of Energy Chemistry》 2025年第2期345-384,I0008,共41页
The pursuit of alternative fuel generation technologies has gained momentum due to the diminishing reserves of fossil fuels and global warming from increased CO_(2)emission.Among the proposed methods,the hydrogenation... The pursuit of alternative fuel generation technologies has gained momentum due to the diminishing reserves of fossil fuels and global warming from increased CO_(2)emission.Among the proposed methods,the hydrogenation of CO_(2)to produce marketable carbon-based products like methanol and ethanol is a practical approach that offers great potential to reduce CO_(2)emissions.Although significant volumes of methanol are currently produced from CO_(2),developing highly efficient and stable catalysts is crucial for further enhancing conversion and selectivity,thereby reducing process costs.An in-depth examination of the differences and similarities in the reaction pathways for methanol and ethanol production highlights the key factors that drive C-C coupling.Identifying these factors guides us toward developing more effective catalysts for ethanol synthesis.In this paper,we explore how different catalysts,through the production of various intermediates,can initiate the synthesis of methanol or ethanol.The catalytic mechanisms proposed by spectroscopic techniques and theoretical calculations,including operando X-ray methods,FTIR analysis,and DFT calculations,are summarized and presented.The following discussion explores the structural properties and composition of catalysts that influence C-C coupling and optimize the conversion rate of CO_(2)into ethanol.Lastly,the review examines recent catalysts employed for selective methanol and ethanol production,focusing on single-atom catalysts. 展开更多
关键词 CO_(2)hydrogenation METHANOL ETHANOL Catalytic mechanism Operando techniques Single atom catalyst Tandem catalyst
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Interdecadal change in the relationship between El Nino-Southern Oscillation and Pacific interior subtropical tropical cells
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作者 xue han Junqiao FENG +2 位作者 Fujun WANG Qingye WANG Dunxin HU 《Journal of Oceanology and Limnology》 2025年第5期1389-1404,共16页
We used the ocean reanalysis dataset SODA 2.2.4 to investigate the relationship between the interior branch of subtropical-tropical cells(STCs)in the Pacific Ocean and El Nino-Southern Oscillation(ENSO)over interdecad... We used the ocean reanalysis dataset SODA 2.2.4 to investigate the relationship between the interior branch of subtropical-tropical cells(STCs)in the Pacific Ocean and El Nino-Southern Oscillation(ENSO)over interdecadal timescales between 1930 and 2010,as well as the possible mechanisms involved.Interior transport within the upper pycnocline layers of STCs(InSTC)along 9°S(InSTC9s)shows a significant correlation of 0.54 with ENSO over the study period.However,there is an interdecadal shift in the relationship between InSTC along 9°N(InSTC9n)and ENSO.The correlation coefficient between InSTC9n and ENSO is not statistically significant between 1930 and 1965(PD1),but is as high as 0.68(significant at the 95% confidence level)between 1965 and 2010(PD2).Composite and regression analysis suggests that this shift may be caused by the relationship between InSTC 9 n and the tropical wind field.During PD1,InSTC9n was driven primarily by the local wind field outside equatorial region,with a relatively weak response to the equatorial wind related to ENSO.In contrast,during PD2,the wind field associated with InSTC 9 n showed a similar spatial distribution to that of ENSO within the equatorial region,indicating a close relationship between InSTC9n and ENSO.The wind stress curl associated with ENSO drives the anomalous InSTC9n in off-equatorial regions,whose signal can propagate westward in the form of Rossby wave and modulate the thermal structure of the tropical Pacific,favoring the development of ENSO.The possible connection between the Atlantic Multidecadal Oscillation(AMO)and interdecadal changes in the ENSO-InSTC9n relationship was also examined.There is a significant connection between the AMO and the interdecadal change in the relationship between ENSO and InSTC9n;however,the associated mechanism remains to be explored in future studies. 展开更多
关键词 interior subtropical-tropical cells(STCs) interdecadal change El Nino-Southern Oscillation(ENSO) Atlantic Multidecadal Oscillation(AMO)
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Low CO content hydrogen production from oxidative steam reforming of ethanol over CuO-CeO_2 catalysts at low-temperature 被引量:1
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作者 xue han Yunbo Yu +1 位作者 Hong He Jiaojiao Zhao 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2013年第6期861-868,共8页
CuO-CeO2 catalysts were prepared by a urea precipitation method for the oxidative steam reforming of ethanol at low-temperature.The catalytic performance was evaluated and the catalysts were characterized by inductive... CuO-CeO2 catalysts were prepared by a urea precipitation method for the oxidative steam reforming of ethanol at low-temperature.The catalytic performance was evaluated and the catalysts were characterized by inductively coupled plasma atomic emission spectroscopy,X-ray diffraction,temperature-programmed reduction,field emission scanning electron microscopy and thermo-gravimetric analysis.Over CuOCeO2 catalysts,H2 with low CO content was produced in the whole tested temperature range of 250–450 C.The non-noble metal catalyst 20CuCe showed higher H2production rate than 1%Rh/CeO2 catalyst at 300–400 C and the advantage was more obvious after 20 h testing at400 C.These results further confirmed that CuO-CeO2 catalysts may be suitable candidates for low temperature hydrogen production from ethanol. 展开更多
关键词 CuO-CeO2 catalyst hydrogen production oxidative steam reforming LOW-TEMPERATURE
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Ⅴ型先天性食管闭锁诊治分析
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作者 黄华 马绍斌 +7 位作者 陈玄玄 薛寒 袁洋 马帅军 马晓宇 黄泓玮 陈琦 冯杰雄 《临床小儿外科杂志》 北大核心 2025年第6期577-581,共5页
目的总结Ⅴ型先天性食管闭锁(congenital esophageal atresia type V, V-CEA)的临床诊治经验。方法回顾性分析郑州大学第三附属医院于2020年9月至2024年6月收治的8例Ⅴ-CEA患儿临床资料。收集患儿一般资料(性别、年龄、体重、临床表现... 目的总结Ⅴ型先天性食管闭锁(congenital esophageal atresia type V, V-CEA)的临床诊治经验。方法回顾性分析郑州大学第三附属医院于2020年9月至2024年6月收治的8例Ⅴ-CEA患儿临床资料。收集患儿一般资料(性别、年龄、体重、临床表现、辅助检查)、手术情况(手术年龄、手术方式、瘘管位置、并发症、再次手术)及预后等。结果 8例患儿中, 男3例、女5例。日龄≤28天4例, 29天至1岁3例, ≥1岁1例。体重1.9~11 kg。均因生后出现呛咳、呼吸困难、呕吐入院。术前食管造影、胸部CT三维重建、纤维支气管镜检查诊断Ⅴ-CEA例数分别为4例、2例、8例。瘘管位于第2胸椎5例, 第7颈椎至第1胸椎2例, 第2胸椎至第3胸椎1例。入院后4~24 d内行经胸腔入路(6例)或左侧颈部入路(2例)手术, 其中胸腔镜联合纤维支气管镜手术(双镜联合)4例, 双镜联合中转开胸手术1例, 开胸联合纤维支气管镜手术1例, 颈部入路联合纤维支气管镜手术2例。术后2例出现声嘶伴吞咽障碍, 无一例吻合口瘘或瘘管复发。随访1~18个月, 1例于术后4个月复发并于本院再次手术;1例于术后3个月复发并于外院再次手术;2例出现轻微呛咳, 于18个月后症状逐渐消失;其余4例无明显并发症。结论胸腔镜手术或开放手术中, 联合纤维支气管镜进行Ⅴ-CEA瘘管定位及修补术安全可行, 具有快速精准定位瘘管、降低手术操作难度、节省手术时间等优点, 术中缝扎离断瘘管并修补气管侧及食管侧瘘口, 可以有效减少术后复发。 展开更多
关键词 食管闭锁 先天性 外科手术 胸外科手术 电视辅助 胸腔镜 纤维支气管镜 治疗结果 手术后并发症
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多电飞机高功率密度高效电机系统热管理技术
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作者 张卓然 张健 +3 位作者 胡光源 薛涵 李涵琪 于立 《航空学报》 北大核心 2025年第6期59-79,共21页
电机是多电飞机供电与电驱动系统的核心单元,在提升飞机综合性能方面发挥关键作用。高效热管理是保障电机系统可靠安全运行以及支撑多电飞机能量优化的重要方向。首先总结了多电飞机上电机系统的作用及其高功率密度高效、高可靠应用特点... 电机是多电飞机供电与电驱动系统的核心单元,在提升飞机综合性能方面发挥关键作用。高效热管理是保障电机系统可靠安全运行以及支撑多电飞机能量优化的重要方向。首先总结了多电飞机上电机系统的作用及其高功率密度高效、高可靠应用特点,从热源、散热条件与应用环境3个层面分析了电机系统面临的热问题和挑战,进一步指出多电飞机电机系统高效冷却和热管理的必要性,论述了电机系统中损耗抑制、热隔离/热传导与热排散等关键技术。在此基础上提出了多电飞机电机系统主动温控和综合热管理概念,从飞机总体及机载系统层面对电机系统的冷却和热管理进行考量,为电机系统核心部件的优化设计提供新思路和要求。 展开更多
关键词 多电飞机 电机系统 冷却 主动温控 综合热管理 能量优化
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Kareem手术矫治小儿肠旋转不良
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作者 黄华 马帅军 +7 位作者 马晓宇 马绍斌 薛寒 陈玄玄 黄泓玮 袁洋 陈琦 冯杰雄 《临床小儿外科杂志》 北大核心 2025年第8期771-775,共5页
目的初步探讨Kareem手术矫治小儿肠旋转不良的可行性及安全性。方法回顾性分析郑州大学第三附属医院新生儿外科2024年1月至2024年11月收治的13例肠旋转不良患儿临床资料。患儿均行Kareem手术治疗。收集患儿一般资料、手术时间、术后疗... 目的初步探讨Kareem手术矫治小儿肠旋转不良的可行性及安全性。方法回顾性分析郑州大学第三附属医院新生儿外科2024年1月至2024年11月收治的13例肠旋转不良患儿临床资料。患儿均行Kareem手术治疗。收集患儿一般资料、手术时间、术后疗效及随访情况。结果13例患儿中,11例因呕吐入院,2例因血便入院;年龄1日龄至10岁;男10例,女3例;5例经术前胃肠超声检查提示肠扭转确诊,8例经术中探查诊断为肠旋转不良。术中5例合并肠扭转,2例合并绞窄性肠梗阻,1例合并先天性小肠闭锁,1例合并先天性膈疝。手术时间(119.46±24.93)min,术后开奶时间6.00(4.50,6.50)d,住院时间(23.00±8.81)d。术后10例喂养顺利,均无呕吐、无再发肠扭转;2例发生粘连性肠梗阻(1例接受保守治疗,1例接受手术治疗),均治愈出院;1例逐渐增加喂养量后出现间断呕吐,经保守治疗未见好转,术中病理检查提示肠神经节细胞发育不良,转外院手术行回肠造口后呕吐好转。结论Kareem手术矫治小儿肠旋转不良,通过使肠-肠系膜结构和血管解剖恢复到正常生理位置,从而避免或减少再发肠扭转,术后短期疗效满意,具有一定的可行性和安全性,可作为矫治小儿肠旋转不良的一种新的术式选择,但远期疗效仍需进一步扩增样本量、开展多中心研究进行随访。 展开更多
关键词 胃肠道 消化系统畸形 肠扭转 外科手术 儿童
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An investigation of changes in water quality throughout the drinking water production/distribution chain using toxicological and fluorescence analyses
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作者 xue han Xin Ji +5 位作者 Xuan Ma Jun-Ling Liu Zhen-Yu He Wei Chang Fei Tang Ai-Lin Liu 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2020年第1期310-318,共9页
Changes in water quality from source water to finished water and tap water at two conventional drinking water treatment plants(DWTPs)were monitored.Beside the routine water quality testing,Caenorhabditis elegans-based... Changes in water quality from source water to finished water and tap water at two conventional drinking water treatment plants(DWTPs)were monitored.Beside the routine water quality testing,Caenorhabditis elegans-based toxicity assays and the fluorescence excitation–emission matrices technique were also applied.Both DWTPs supplied drinking water that met government standards.Under current test conditions,both the investigated finished water and tap water samples exhibited stronger lethal,genotoxic and reprotoxic potential than the relative source water sample,and the tap water sample was more lethal but tended to be less genotoxic than the corresponding finished water sample.Meanwhile,the nearly complete removal of tryptophan-like substances and newly generated tyrosine-like substances were observed after the treatment of drinking water,and humic-like substances were identified in the tap water.Based on these findings,toxic pollutants,including genotoxic/reproductive toxicants,are produced in the drinking water treatment and/or distribution processes.Moreover,further studies are needed to clarify the potentially important roles of tyrosine-like and humic-like substances in mediating drinking water toxicity and to identify the potential sources of these contaminants.Additionally,tryptophan-like fluorescence may be adopted as a useful parameter to monitor the treatment performance of DWTPs.Our observations provided insights into the importance of utilizing biotoxicity assays and fluorescence spectroscopy as tools to complement the routine evaluation of drinking water. 展开更多
关键词 BIOASSAY C.elegans EEM Water treatment Distribution system
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Responses of food production systems to climate change:sensitivity and vulnerability
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作者 Liyong Xie Yue Li +3 位作者 Fengkui Qian Hongliang Zhao xue han Erda Lin 《Chinese Journal of Population,Resources and Environment》 2014年第3期227-232,共6页
Climate warming has prolonged the optimization of crop-growing seasons,shortened actual growth periods,and changed crop-planting boundaries.It also has boosted crop yields in certain regions while compromising crop qu... Climate warming has prolonged the optimization of crop-growing seasons,shortened actual growth periods,and changed crop-planting boundaries.It also has boosted crop yields in certain regions while compromising crop quality and affected the occurrence of meteorological disasters and pest diseases damage,which has resulted in reduction in grain yield.Crop production systems will evidence more sensitivity to climate change in future;for example,with an increase of 1°C in temperature,the average growth period will be shortened by 17 days for winter wheat and 7-8 days for maize and rice.Of course regional differences will exist.Climate change will threaten crop yield stability and affect crop quality.Vulnerability will be addressed in regard to extreme climatic events,which include reducing exposure and improving adaptive capacity,because the exposure of rain-fed agriculture is greater than that of irrigated agriculture.Therefore,we propose three suggestions to reduce the vulnerability of crop production systems to climate change.First,strengthen the evaluation capacity construction of sensitivity,which includes(1)refining and improving all types of evaluation indicator systems and models;(2)innovating and developing evaluation methods and tools;and(3)combining field observation and case studies,so that(1)the impact of climate change and sensitivity can be assessed scientifically;(2)uncertainty in the study can be identified and reduced;and(3)improved understanding of climate systems and their changes,climate change impact,and sensitivity will be achieved.Second,strengthen adaptive capacity construction for crop production systems,which includes(1)rebuilding existing farmland infrastructure to improve meteorological disaster defences;(2)adjusting agriculture structure and adopting new crop varieties with enhanced resistance;(3)popularizing water-saving technology and dry farming technology;and(4)further researching interdisciplinary theories and methods.Third,strengthen function construction for natural and social systems,which includes(1)popularizing innovative technology;(2)progressing agricultural insurance;and(3)improving energy efficiency and increasing carbon sequestration and emission reduction ability to maintain a favorable ecological environment. 展开更多
关键词 CLIMATE change FOOD production impact and adaptation sensitivity VULNERABILITY EXPOSURE RESILIENCE
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The Flipping-Free Full-Parallax Tabletop Integral Imaging with Enhanced Viewing Angle Based on Space-Multiplexed Voxel Screen and Compound Lens Array
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作者 Peiren Wang Jinqiang Bi +3 位作者 Zilong Li xue han Zhengyang Li Xiaozheng Wang 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第9期3197-3211,共15页
Tabletop integral imaging display with a more realistic and immersive experience has always been a hot spot in three-dimensional imaging technology,widely used in biomedical imaging and visualization to enhance medica... Tabletop integral imaging display with a more realistic and immersive experience has always been a hot spot in three-dimensional imaging technology,widely used in biomedical imaging and visualization to enhance medical diagnosis.However,the traditional structural characteristics of integral imaging display inevitably introduce the flipping effect outside the effective viewing angle.Here,a full-parallax tabletop integral imaging display without the flipping effect based on space-multiplexed voxel screen and compound lens array is demonstrated,and two holographic functional screens with different parameters are optically designed and fabricated.To eliminate the flipping effect in the reconstruction process,the space-multiplexed voxel screen consisting of a projector array and the holographic functional screen is presented to constrain light beams passing through the corresponding lens.To greatly promote imaging quality within the viewing area,the aspherical structure of the compound lens is optimized to balance the aberrations.It cooperates with the holographic functional screen to modulate the light field spatial distribution.Compared with the simulation results,the distortion rate of the imaging display is reduced to less than 9%from more than 30%.In the experiment,the floating high-quality reconstructed three-dimensional image without the flipping effect can be observed with the correct 3D perception at 96°×96°viewing angle,where 44,100 viewpoints are employed. 展开更多
关键词 Integral imaging display flipping effect large viewing angle optimized compound lens imaging distortion
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More than a Few LAB Alleviate Common Allergies: Impact of Paraprobiotics in Comparison to Probiotical Live Cells
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作者 Nditange Shigwedha Lanwei Zhang +7 位作者 Liubov Sichel Li Jia Pimin Gong Wenli Liu Shumei Wang Shuang Zhang xue han Wei Gao 《Journal of Biosciences and Medicines》 2014年第3期56-64,共9页
The evidence in this paper indicates that the alarming increase of common allergies can be reduced by the intake of particular “probiotics” or “paraprobiotics” along with food. This appears to build a consensus in... The evidence in this paper indicates that the alarming increase of common allergies can be reduced by the intake of particular “probiotics” or “paraprobiotics” along with food. This appears to build a consensus in the pharmaceutical and food communities about the role of probiotics in the prevention and treatments of common allergies. Food allergy is one of the common allergies, defined as an adverse health effect arising from a specific immune response that occurs reproducibly on exposure to a given food. Improving the digestion of foods and maintaining a healthy gastrointestinal (GI) tract is certainly critical to controlling food allergens. Therefore, the association between a leaky gut or an impaired intestinal permeability and food-allergenic reactions is explained. Gluten has been found to be somehow a justification for protein allergy, and should, therefore, be avoided by people with celiac disease. In several, in vitro models, surface layer (S- layer) proteins of selective paraprobiotics have shown potential in alleviating food allergies and intestinal disorders. Notably, lactobacilli paraprobiotics have proven to be the immediate immunomodulators against common allergies and other diseases, including viral (flu, hepatitis C), bacterial (bronchitis), asthma, chronic fatigue, fibromyalgia, gastrointestinal distress, and autism disorders in humans. 展开更多
关键词 Paraprobiotics Food ALLERGY S-LAYER Proteins IMMUNOGLOBULIN E (IgE) Probiotical Cell Lysates LACTIC Acid Bacteria (LAB)
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The potential mechanism of prevention and treatment of COVID-19 by shufeng jiedu capsule was studied based on network pharmacology
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作者 Jing-Wen Huang Li-Feng An +4 位作者 xue han Qing-Wei Li Hui xue Liu Yang Jian-Fei Duan 《Journal of Hainan Medical University》 2020年第11期13-17,共5页
Objective: To investigate the mechanism of Shufeng Jiedu Capsule(SJC) for treatment of COVID-19 based on network pharmacology. Methods: Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform ... Objective: To investigate the mechanism of Shufeng Jiedu Capsule(SJC) for treatment of COVID-19 based on network pharmacology. Methods: Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform (TCMSP) was used to obtain the active components and targets information of Polygoni Cuspidati Rhizoma Et Radix, Forsythiae Fructus, Istidis Radix, Radix Bupleuri, Herba Patriniae, Verbenae Herb, Phragmitis Rhizoma and licorice in SJC. The Genecards databases were used to obtain COVID-19 targets. The meridian tropisms of each herb in SJC were collected from ETCM Database.the proteins interations network were build by STRING database. The GO and KEGG pathways were analyzed by the computer R language. Results: SFC contains 8herbs, 176 compounds and the corresponding targets 237. 48 COVID-19 targets are treated by SJC. Such as IL-10, IL-6, PTGS1, PTGS2, GSK3B, STAT-1, IL-17 signaling pathway, HIF-1 signaling pathway, Toll-like receptor signaling pathway, T cell receptor signaling pathway and VEGF signaling pathway may be potential targets and signaling pathways for the prevention and treatment of COVID-19. Conclusion: The COVID-19 cantreatmented the potential targets and signaling pathways by the SJC, and play the role of antipyretic, anti-inflammatory, balance immunity, antiviral and so on. It will provide strong support for the later stage experiment and clinical application of SJC. 展开更多
关键词 Shufeng Jiedu Capsule Corona Virus Disease 2019(COVID-19) Network pharmacology TARGET Signaling pathway
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2022—2024年北京市大兴区肺结核合并糖尿病及高血压患者的流行特征及治疗转归情况
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作者 侯文俊 田飞飞 +4 位作者 张时雨 张耀文 豆亚美 薛涵 崔虹艳 《结核与肺部疾病杂志》 2025年第5期579-586,共8页
目的:描述大兴区2022—2024年登记肺结核患者合并糖尿病及高血压的流行病学特征,分析治疗转归的影响因素,为肺结核与慢性病共病防治提供依据。方法:通过“中国疾病预防控制信息系统”子系统“结核病管理信息系统”收集大兴区2022—2024... 目的:描述大兴区2022—2024年登记肺结核患者合并糖尿病及高血压的流行病学特征,分析治疗转归的影响因素,为肺结核与慢性病共病防治提供依据。方法:通过“中国疾病预防控制信息系统”子系统“结核病管理信息系统”收集大兴区2022—2024年登记的肺结核患者信息,结合基本公共卫生服务信息系统、医院信息系统、居民电子健康档案、问卷,调查合并糖尿病及高血压情况,对其流行特征与治疗转归情况进行分析。结果:共992例肺结核患者纳入分析,12.10%(120/992)合并糖尿病,17.14%(170/992)合并高血压,16.73%(166/992)合并糖尿病和高血压。男性[14.63%(90/615)、19.03%(117/615)、18.37%(113/615)]、农民[15.26%(18/118)、32.20%(38/118)、25.42%(30/118)]、本地[12.36%(91/736)、20.25%(149/736)、19.97%(147/736)]、病原学阳性[14.87%(88/592)、18.24%(108/592)、20.27%(120/592)]的肺结核患者合并糖尿病、高血压、糖尿病和高血压比例均较高,45~64岁年龄组肺结核合并糖尿病[15.50%(42/271)],≥65岁年龄组肺结核合并高血压[36.30%(102/281)]、合并糖尿病和高血压[30.25%(85/281)]比例较高。复治患者合并糖尿病[27.59%(16/58)],初治患者合并高血压[17.67%(165/934)]、合并糖尿病和高血压[17.24%(161/934)]比例较高。肺结核合并糖尿病患者治疗疗程最长[371.00(274.25,398.00)d],肺结核合并高血压患者治疗疗程最短[234.00(192.00,321.75)d](Z=48.189,P<0.001)。多因素logistic回归分析结果显示,≥65岁年龄组(OR=3.105,95%CI:1.378~7.113)、复治(OR=6.372,95%CI:2.074~19.663)、合并糖尿病(OR=4.717,95%CI:1.529~14.078)的患者发生不良结局的风险较高,疗程长(OR=0.980,95%CI:0.976~0.984)发生不良结局的风险较低。结论:大兴区合并糖尿病和高血压的肺结核患者集中在男性、年龄较大、农民、本地、病原学阳性,合并糖尿病患者有复治、治疗疗程长的特点,肺结核合并高血压患者有初治、治疗疗程短的特点。年龄大、复治、合并糖尿病、治疗疗程短的肺结核患者发生不良结局的风险较高。 展开更多
关键词 结核 糖尿病 高血压 共病现象 治疗结果
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新型关节韧带数字体查仪量化评估前交叉韧带部分损伤后的膝关节松弛度 被引量:2
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作者 朱哲越 张晨 +4 位作者 葛莹 薛晗 李若尘 吴光伟 马瑞 《中国组织工程研究》 CAS 北大核心 2025年第27期5795-5801,共7页
背景:前交叉韧带部分损伤后膝关节松弛程度的量化测量对于及时诊断、后期治疗和康复非常重要。现缺乏应用关节韧带测量仪进行前交叉韧带部分损伤诊断的相关研究。目的:探讨新型关节韧带数字体查仪在前交叉韧带部分损伤中的诊断价值。方... 背景:前交叉韧带部分损伤后膝关节松弛程度的量化测量对于及时诊断、后期治疗和康复非常重要。现缺乏应用关节韧带测量仪进行前交叉韧带部分损伤诊断的相关研究。目的:探讨新型关节韧带数字体查仪在前交叉韧带部分损伤中的诊断价值。方法:纳入30名单侧前交叉韧带部分损伤患者及20名健康志愿者作为研究对象,应用国产新型关节韧带数字体查仪测量80,120,150 N三种负荷下每侧膝关节的胫骨向前位移值,比较前交叉韧带部分损伤组和对照组的胫骨向前位移值和双侧差异值,分析受试者工作特征曲线,计算曲线下面积,并确定新型关节韧带数字体查仪的诊断灵敏度及特异度。结果与结论:①前交叉韧带部分损伤组和对照组在年龄、性别、体质量指数和病程方面差异均无显著性意义(P>0.05);②前交叉韧带部分损伤组胫骨向前位移值的双侧差异值明显高于对照组(P<0.05),且前交叉韧带部分损伤组患侧的胫骨向前位移值明显高于健侧(P<0.05);③施加负荷在80 N时的诊断准确性最高(cutoff值=10.45 mm),曲线下面积为0.813(95%CI:0.708-0.919),敏感性和特异性分别为76.7%和70.0%;④提示新型关节韧带数字体查仪可以客观量化评估前交叉韧带部分损伤后的膝关节松弛度,可为怀疑前交叉韧带部分损伤的患者提供客观的诊断依据。 展开更多
关键词 前交叉韧带 前交叉韧带损伤 膝关节松弛 胫骨前移 数字化关节测量
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电能航空动力技术发展研究 被引量:2
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作者 邵凌云 张卓然 +3 位作者 高华敏 黄维康 薛涵 徐岳 《中国工程科学》 北大核心 2025年第2期25-38,共14页
电能航空动力技术开启了航空领域新一轮创新与变革热潮,是推进航空业绿色发展、应对全球环境挑战的重要举措。本文系统论述了国内外电动航空器的研究进展,分析了我国电能航空动力技术与国外的差距,明晰了我国电动航空器研制所面临的技... 电能航空动力技术开启了航空领域新一轮创新与变革热潮,是推进航空业绿色发展、应对全球环境挑战的重要举措。本文系统论述了国内外电动航空器的研究进展,分析了我国电能航空动力技术与国外的差距,明晰了我国电动航空器研制所面临的技术挑战;进一步梳理了电能航空动力四大关键技术:长寿命高能量密度电池技术、高效高功重比电机推进技术、能量综合管理技术和高升阻比气动布局设计技术,分析了各关键技术的产业特征和研究现状,阐明了各关键技术的发展方向和亟待解决的基础技术问题;构建了电能航空动力飞机性能评估模型,分析了电池能量密度、电机功率密度、电机效率和飞机升阻比等关键技术参数对电动航空器性能的影响,评估了电能航空动力技术在轻小型城市空运飞机、区域通勤飞机和小型支线飞机上的工程实用性。研究建议,电能航空动力技术发展应充分利用我国拥有的新能源产业的技术积累和先进工业基础,考虑高能量密度储能电池、高效能推进系统等关键部件的现有性能与未来提升需求,以城市空运、区域通勤、支线飞机为路径制定发展战略规划,逐步拓展电能航空动力技术在民航运输中的应用,助力我国实现碳达峰、碳中和目标。 展开更多
关键词 电能航空动力 电动航空器 电推进 绿色航空 储能电池
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高效抑制松材线虫的复合木腐菌筛选
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作者 原燕枝 余璐 +7 位作者 胡坚 顾蝶 薛寒 李永 汪来发 程相称 韩珊 王曦茁 《林业科学》 北大核心 2025年第11期116-124,共9页
【目的】筛选一组能够高效抑制松材线虫的复合木腐菌,为研发松材线虫病伐桩的环保除治新方式提供理论依据。【方法】以17组复合木腐菌为对象,分别测定白腐菌(W)与褐腐菌(B)共培养过程中的抑制率,以此作为初步筛选标准获得15组复合木腐菌... 【目的】筛选一组能够高效抑制松材线虫的复合木腐菌,为研发松材线虫病伐桩的环保除治新方式提供理论依据。【方法】以17组复合木腐菌为对象,分别测定白腐菌(W)与褐腐菌(B)共培养过程中的抑制率,以此作为初步筛选标准获得15组复合木腐菌;观察计算松材线虫在复合培养木腐菌平板上的死亡率,获得对松材线虫具有抑制作用的复合木腐菌;将红松和马尾松接种至含有复合木腐菌的培养瓶中,分别培养一定时间后获得降解率高的复合木腐菌。将筛选得到的复合木腐菌W5473:B80995(桦褶孔菌与红缘拟层孔菌)进行傅里叶红外光谱分析,明确红松和马尾松的降解情况;将复合木腐菌制成微生物菌剂应用于林间,统计分析伐桩内松材线虫数量的变化和伐桩的降解率,获得菌剂的林间应用效果。【结果】1)17组复合木腐菌中,2组复合木腐菌在培养过程中始终存在抑制作用,选择其余15组相互间没有持续性抑制作用的复合木腐菌作为下一步筛选试验的材料。2)初步筛选试验获得的15组复合木腐菌中,9组复合木腐菌对松材线虫的抑制作用达到100%,14组复合木腐菌中的松材线虫死亡率大于88%;在复合木腐菌降解红松和马尾松的第30、60、90天,W5473:B80995的降解率显著高于其他复合木腐菌,综合松材线虫死亡率与木块降解率的试验结果,选择W5473:B80995作为下一步试验的材料。3)W5473:B80995对马尾松的降解率高于红松,木质素降解缓慢,降解速率低于纤维素和半纤维素。降解至第90天时,半纤维素降解基本完成,马尾松纤维素的降解速率显著减缓并趋于稳定,而红松纤维素仍保持较高的降解速率。【结论】通过对17组复合木腐菌进行筛选,获得复合木腐菌W5473:B80995。该复合木腐菌对松材线虫的抑制率达96.7%;在第90天时对红松的降解率达37.58%,对马尾松的降解率达49.88%,具有良好的应用前景。相较于红松,该复合木腐菌对马尾松的降解效率更高。降解过程中,纤维素和半纤维素的分解主要集中在前中期,木质素则较难分解;降解后期,马尾松的物质降解基本趋于稳定。经复合木腐菌处理后,伐桩内松材线虫数量减少,伐桩质量显著降低,伐桩内松材线虫数量减少率与伐桩降解率具有正相关关系。 展开更多
关键词 复合木腐菌 松材线虫 伐桩除治 降解率
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基于流固耦合的管式离心机流场特性与转子动力学仿真研究 被引量:1
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作者 薛翰 王野平 周育岭 《机电工程技术》 2025年第3期14-20,共7页
以管式离心机为研究对象,基于流固耦合的数值仿真方法,主要针对管式离心机两个方面的问题进行仿真研究,一方面是流场特性研究;另一方面是转子动力学问题研究。在这两个方面的研究中,依次选取5种工作转速开展分析(12000、13000、14000、1... 以管式离心机为研究对象,基于流固耦合的数值仿真方法,主要针对管式离心机两个方面的问题进行仿真研究,一方面是流场特性研究;另一方面是转子动力学问题研究。在这两个方面的研究中,依次选取5种工作转速开展分析(12000、13000、14000、15000和16000 r/min)。首先研究流场的压力分布和相分布,采用Mixture多相流模型和RNG k-ε湍流模型进行稳态分析,最终得到流场的最大压力值,其值与工作转速正相关,依次为1.85、2.14、2.44、2.76及3.10 MPa,并进一步通过二次多项式拟合出转速-最大压力间的函数关系式。其次,研究转子结构的强度和临界转速,在强度分析中,校核了当使用316不锈钢为主体材料时的结构强度,结果表明其满足强度要求;在临界转速分析中,使用预应力模态分析的方法,计算出了转子结构在不同工作转速下的前6阶固有频率值,通过绘制坎贝尔图发现临界转速为13172.175 r/min,并且临界转速接近第3阶固有频率:219.104、219.471、219.850、220.245和220.658 Hz。所建立的数值仿真模型和研究结果,对管式离心机的设计和实际应用具有一定参考价值和指导意义。 展开更多
关键词 离心分离 流固耦合 Mixture多相流模型 强度分析 临界转速
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黄芩汤自组装纳米粒凝胶的制备及其抗皮肤癣菌作用评价
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作者 闵红燕 薛涵 +3 位作者 高聪颖 邓冯沂 章佩 沈成英 《中国医院药学杂志》 北大核心 2025年第19期2208-2217,共10页
目的:研制一种治疗皮肤浅部真菌病的黄芩汤自组装纳米粒凝胶(HQD-N-gel),并评价其抗皮肤癣菌作用。方法:采用高速离心结合透析法制备黄芩汤自组装纳米粒(HQD-N),进一步将其制成凝胶剂(gel)。以丙二醇浓度、HQD-N加入量和卡波姆940浓度... 目的:研制一种治疗皮肤浅部真菌病的黄芩汤自组装纳米粒凝胶(HQD-N-gel),并评价其抗皮肤癣菌作用。方法:采用高速离心结合透析法制备黄芩汤自组装纳米粒(HQD-N),进一步将其制成凝胶剂(gel)。以丙二醇浓度、HQD-N加入量和卡波姆940浓度为考察因素,以粒径、多分散系数(PDI)、Zeta电位、黄芩苷12 h体外释放量、黄芩苷12 h皮肤透过量及皮肤滞留量为考察指标,采用Box-Behnken效应面法优化处方。对最优处方制备的HQD-N-gel进行表征和抗菌效果评价。结果:以最优处方(12.0 mg·g^(-1)卡波姆940、86.0 mg·g^(-1) HQD-N、60.0 mg·g^(-1)丙二醇)制得的HQD-N-gel粒径为(355.67±19.04)nm,PDI为0.31±0.01,Zeta电位为–(34.73±1.32) mV,黄芩苷12 h体外释放量为(41.09±2.42)%,黄芩苷12 h皮肤透过量为(74.25±12.94)μg·cm^(-2)以及皮肤滞留量为(4.54±1.78) mg·g^(-1),实际测得值与模型预测值接近,模型具有良好的预测性。HQD-N-gel外观性质良好,pH适中,形态大小均匀,能有效抑制皮肤癣菌的生长。结论:HQD-N-gel具有良好的抗皮肤癣菌作用。 展开更多
关键词 黄芩汤 自组装纳米粒 凝胶 处方优化 抗皮肤癣菌
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毛樱桃果实炭疽病的病原形态与分子鉴定
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作者 姜宁 薛寒 李永 《植物病理学报》 北大核心 2025年第2期348-351,共4页
毛樱桃(Prunus tomentosa)是蔷薇科(Rosaceae)落叶灌木,是我国西部和北部常见的绿化和药食用树种。该树种的病害较少,但在2021一2023年的病害调查中,发现北京和山东的毛樱桃果实上出现明显的炭疽病症状。经调查统计,毛樱桃果炭疽病的发... 毛樱桃(Prunus tomentosa)是蔷薇科(Rosaceae)落叶灌木,是我国西部和北部常见的绿化和药食用树种。该树种的病害较少,但在2021一2023年的病害调查中,发现北京和山东的毛樱桃果实上出现明显的炭疽病症状。经调查统计,毛樱桃果炭疽病的发病率在0.3%~2.7%,对其食药用价值造成一定的影响。发病初期,病果上出现黄色的椭圆形病斑,随后病斑扩展变大,病处凹陷,果实变得腐烂皱缩,病斑处能形成橘黄色的分生孢子团(图1-A)。 展开更多
关键词 病原形态 炭疽病 分子鉴定 发病率 毛樱桃
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腔镜矫治新生儿隔膜型高位空肠闭锁疗效分析
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作者 薛寒 黄华 +7 位作者 马绍斌 马帅军 马晓宇 袁洋 陈玄玄 黄泓玮 陈琦 冯杰雄 《腹部外科》 2025年第3期185-189,共5页
目的探讨完全腹腔镜技术矫治Ⅰ型(隔膜型)新生儿高位空肠闭锁的临床疗效。方法回顾性分析2017年1月至2024年9月郑州大学第三附属医院收治的46例隔膜型高位空肠闭锁(距Treitz韧带10 cm以内)新生儿的临床资料,根据手术方式的不同分为完全... 目的探讨完全腹腔镜技术矫治Ⅰ型(隔膜型)新生儿高位空肠闭锁的临床疗效。方法回顾性分析2017年1月至2024年9月郑州大学第三附属医院收治的46例隔膜型高位空肠闭锁(距Treitz韧带10 cm以内)新生儿的临床资料,根据手术方式的不同分为完全腹腔镜(laparoscopic procedure,LP)组(16例)和开腹(open procedure,OP)组(30例)。LP组均采用完全腹腔镜技术行隔膜切除肠闭锁矫治术;OP组均采用传统开腹手术。比较两组患儿的一般资料、围手术期炎症指标、手术持续时间、术中出血量、术后首次排便时间、术后喂养情况、术后腹腔引流管拔除时间、术后并发症、非计划二次手术、住院时间以及死亡人数的差异。对于服从或近似正态分布的计量资料采用t检验,采用x±s进行描述;对于不符合正态性的连续变量,运用M(Q_(1),Q_(3))的形式来进行描述,计数资料的组间比较选取χ^(2)检验。结果两组患儿均顺利完成手术。两组在性别、胎龄、体重、早产率、产前诊断异常等一般临床资料间进行比较,差异均无统计学意义(均P>0.05)。LP组相比于OP组,术中出血量减少[2.00(1.00,2.38)mL比2.00(2.00,5.25)mL],差异有统计学意义(P<0.05)。LP组相比于OP组,术后首次排便时间缩短[(2.25±1.24)d比(3.20±1.37)d]、术后首次开奶时间缩短[(7.19±2.07)d比(9.00±3.18)d]、完全肠内喂养时间缩短[(15.56±6.77)d比(23.43±14.94)d]、腹腔引流管拔除时间缩短[(10.43±3.67)d比(13.47±4.98)d]、住院时间缩短[(21.50±7.30)d比(29.50±14.21)d],差异均有统计学意义(均P<0.05)。两组在手术前后C反应蛋白、手术持续时间、术后并发症、非计划二次手术、死亡人数方面比较,差异均无统计学意义(均P>0.05)。结论完全腹腔镜技术治疗新生儿隔膜型高位空肠闭锁安全可行,具有出血少、胃肠功能恢复早、住院时间缩短等优点。 展开更多
关键词 完全腹腔镜 开腹 高位空肠闭锁 新生儿 治疗
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基于多模态残差网络融合波形与天气信息的输电线路故障原因辨识方法
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作者 林丰恺 王建 +3 位作者 赵启 薛汉 彭寅章 南东亮 《电力系统保护与控制》 北大核心 2025年第20期23-33,共11页
针对现有基于暂态波形图像识别的输电线路故障原因辨识,因使用的输入特征相对单一而无法进一步细分故障原因的问题,基于多模态残差网络,提出了一种融合暂态波形与天气特征的输电线路故障原因辨识方法。首先,统计分析了不同原因的输电线... 针对现有基于暂态波形图像识别的输电线路故障原因辨识,因使用的输入特征相对单一而无法进一步细分故障原因的问题,基于多模态残差网络,提出了一种融合暂态波形与天气特征的输电线路故障原因辨识方法。首先,统计分析了不同原因的输电线路故障在暂态波形和天气条件方面的特征差异。其次,以暂态波形图像和故障发生时天气情况的独热编码作为改进多模态残差网络分类器的输入。然后,利用通道注意力机制对网络提取得到的故障暂态波形图像特征和天气特征进行特征融合,实现多模态输电线路故障辨识模型的训练与测试。最后,完全采用真实故障录波数据开展了算例验证。结果表明:所提方法对故障原因的辨识准确率达到了94.87%。相比于传统的故障辨识方法,网络所需的故障特征量更少、对易混淆故障的辨识效果更好、辨识准确度更高。 展开更多
关键词 输电线路 故障辨识 多模态 残差网络 天气特征
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