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Heterointerface Engineering-Induced Oxygen Defects for the Manganese Dissolution Inhibition in Aqueous Zinc Ion Batteries 被引量:2
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作者 Wentao Qu Yong Cai +1 位作者 Baohui Chen Ming Zhang 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2024年第3期112-122,共11页
Manganese-based material is a prospective cathode material for aqueous zinc ion batteries(ZIBs)by virtue of its high theoretical capacity,high operating voltage,and low price.However,the manganese dissolution during t... Manganese-based material is a prospective cathode material for aqueous zinc ion batteries(ZIBs)by virtue of its high theoretical capacity,high operating voltage,and low price.However,the manganese dissolution during the electrochemical reaction causes its electrochemical cycling stability to be undesirable.In this work,heterointerface engineering-induced oxygen defects are introduced into heterostructure MnO_(2)(δa-MnO_(2))by in situ electrochemical activation to inhibit manganese dissolution for aqueous zinc ion batteries.Meanwhile,the heterointerface between the disordered amorphous and the crystalline MnO_(2)ofδa-MnO_(2)is decisive for the formation of oxygen defects.And the experimental results indicate that the manganese dissolution ofδa-MnO_(2)is considerably inhibited during the charge/discharge cycle.Theoretical analysis indicates that the oxygen defect regulates the electronic and band structure and the Mn-O bonding state of the electrode material,thereby promoting electron transport kinetics as well as inhibiting Mn dissolution.Consequently,the capacity ofδa-MnO_(2)does not degrade after 100 cycles at a current density of 0.5 Ag^(-1)and also 91%capacity retention after 500cycles at 1 Ag^(-1).This study provides a promising insight into the development of high-performance manganese-based cathode materials through a facile and low-cost strategy. 展开更多
关键词 electrochemical activation HETEROINTERFACE manganese dissolution inhibition oxygen defects zinc ion batteries
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Progress on Transition Metal Ions Dissolution Suppression Strategies in Prussian Blue Analogs for Aqueous Sodium-/Potassium-Ion Batteries 被引量:2
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作者 Wenli Shu Junxian Li +3 位作者 Guangwan Zhang Jiashen Meng Xuanpeng Wang Liqiang Mai 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第7期142-168,共27页
Aqueous sodium-ion batteries(ASIBs)and aqueous potassium-ion batteries(APIBs)present significant potential for large-scale energy storage due to their cost-effectiveness,safety,and environmental compatibility.Nonethel... Aqueous sodium-ion batteries(ASIBs)and aqueous potassium-ion batteries(APIBs)present significant potential for large-scale energy storage due to their cost-effectiveness,safety,and environmental compatibility.Nonetheless,the intricate energy storage mechanisms in aqueous electrolytes place stringent require-ments on the host materials.Prussian blue analogs(PBAs),with their open three-dimensional framework and facile synthesis,stand out as leading candidates for aqueous energy storage.However,PBAs possess a swift capacity fade and limited cycle longevity,for their structural integrity is compromised by the pronounced dis-solution of transition metal(TM)ions in the aqueous milieu.This manuscript provides an exhaustive review of the recent advancements concerning PBAs in ASIBs and APIBs.The dissolution mechanisms of TM ions in PBAs,informed by their structural attributes and redox processes,are thoroughly examined.Moreover,this study delves into innovative design tactics to alleviate the dissolution issue of TM ions.In conclusion,the paper consolidates various strategies for suppressing the dissolution of TM ions in PBAs and posits avenues for prospective exploration of high-safety aqueous sodium-/potassium-ion batteries. 展开更多
关键词 Prussian blue analogs Transition metal ions dissolution Suppression strategies Aqueous sodium-ion batteries Aqueous potassium-ion batteries
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Dissolution behavior of Al_(2)O_(3)inclusions into CaO-MgO-SiO_(2)-Al_(2)O_(3)-TiO_(2)system ladle slags
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作者 Zhiyin Deng Xiaomeng Zhang +2 位作者 Guangyu Hao Chunxin Wei Miaoyong Zhu 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第5期977-987,共11页
To investigate the dissolution behaviors of Al_(2)O_(3)inclusions in CaO-5wt%MgO-SiO_(2)-30wt%Al_(2)O_(3)-TiO_(2)system ladle slags,confocal scanning laser microscopy was conducted on the slags with different TiO_(2)c... To investigate the dissolution behaviors of Al_(2)O_(3)inclusions in CaO-5wt%MgO-SiO_(2)-30wt%Al_(2)O_(3)-TiO_(2)system ladle slags,confocal scanning laser microscopy was conducted on the slags with different TiO_(2)contents(0-10wt%),and scanning electron microscopy was performed to study the interfacial reaction between Al_(2)O_(3)and this slag system.The results disclose that the dissolution of Al_(2)O_(3)inclusions does not result in the formation of new phases at the boundary between the slag and the inclusions.In TiO_(2)-bearing and TiO_(2)-free ladle slags,there is no difference in the dissolution mechanism of Al_(2)O_(3)inclusions at steelmaking temperatures.Boundary layer diffusion is found as the controlling step of the dissolution of Al_(2)O_(3),and the diffusion coefficient is in the range of 4.18×10^(-10)to 2.18×10^(-9)m^(2)/s at 1450-1500℃.Compared with the solubility of Al_(2)O_(3)in the slags,slag viscosity and temperature play a more profound role in the dissolution of Al_(2)O_(3)inclusions.A lower viscosity and a lower melting point of the slags are beneficial for the dissolution.Suitable addition of TiO_(2)(e.g.,5wt%)in ladle slags can enhance the dissolution of Al_(2)O_(3)inclusions because of the low viscosity and melting point of the slags,while excessive addition of TiO_(2)(e.g.,10wt%)shows the opposite trend. 展开更多
关键词 INCLUSIONS dissolution ladle refining slag titanium dioxide confocal scanning laser microscopy
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Zn Dissolution-Passivation Behavior with ZnO Formation via In Situ Characterizations
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作者 Tanyanyu Wang Masahiro Kunimoto +3 位作者 Masahiro Yanagisawa Masayuki Morita Takeshi Abe Takayuki Homma 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2024年第1期193-200,共8页
In this study,ZnO formation during the dissolution-passivation process of Zn anodes is observed via in situ Raman and optical characterization.The Zn passivation during galvanostatic anodization merely follows the dis... In this study,ZnO formation during the dissolution-passivation process of Zn anodes is observed via in situ Raman and optical characterization.The Zn passivation during galvanostatic anodization merely follows the dissolution-precipitation model,whereas that of potentiodynamic polarization exhibits different behaviors in different potential ranges.Initially,the Zn electrode is gradually covered by a ZnO precipitation film and then undergoes solid-state oxidation at~255 mV.The starting point of solid-state oxidation is well indicated by the abrupt current drop and yellow coloration of the electrode surface.During the pseudo passivation,an intense current oscillation is observed.Further,blink-like color changes between yellow and dark blue are revealed for the first time,implying that the oscillation is caused by the dynamic adsorption and desorption of OH groups.The as-formed ZnOs then experience a dissolution-reformation evolution,during which the crystallinity of the primary ZnO film is improved but the solid-state-formed ZnO layer becomes rich in oxygen vacancies.Eventually,oxide densification is realized,contributing to the Zn passivation.This study provides new insights into the Zn dissolution-passivation behavior,which is critical for the future optimization of Zn batteries. 展开更多
关键词 in situ characterization Zn dissolution and passivation ZnO formation
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Effect of Slag Basicity on Alumina Dissolution and Diffusivity:A High-temperature Confocal Laser Scanning Microscopy Study
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作者 Burhanuddin Harald HARMUTH 《China's Refractories》 CAS 2024年第2期27-34,共8页
Alumina is one of the crucial and extensively utilized refractory components.As the refractory wear due to dissolution at elevated temperatures during operation is a major threat to refractory lifespan,quantifying dis... Alumina is one of the crucial and extensively utilized refractory components.As the refractory wear due to dissolution at elevated temperatures during operation is a major threat to refractory lifespan,quantifying dissolution is important for developing cost-effective and resource-efficient refractories.This study investigated the dissolution of alumina particles in two silicate and one calcium aluminate slags at 1450,1500,and 1550°C using high-temperature confocal laser scanning microscopy(HT-CLSM).Dissolution was quantified in terms of diffusivity,with all influencing factors,including Stefan flow and bath movement,incorporated into the determination process.The trends observed in total dissolution time and diffusivity in three slags at three experimental temperatures could not be explained solely on the basis of slag basicity.Two parameters,considering the influencing factors,were introduced to explain these trends.Furthermore,the linear trend observed in Arrhenius plots of diffusivities supports the diffusivity results.Additionally,good agreement between the diffusivities of alumina in one silicate slag obtained via CLSM and rotating finger test investigations verified the reliability of the results. 展开更多
关键词 ALUMINA dissolution DIFFUSIVITY CORROSION REFRACTORY
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Later-Life Marital Dissolution in Italy:An Emerging Phenomenon?
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作者 Laura Arosio 《Sociology Study》 2024年第2期98-106,共9页
The phenomenon of marital dissolution in later life,also referred to as“gray divorce”,is described on the rise in contemporary Western societies.This article contributes to the study of marriage breakdown in older a... The phenomenon of marital dissolution in later life,also referred to as“gray divorce”,is described on the rise in contemporary Western societies.This article contributes to the study of marriage breakdown in older age,with a specific focus on Italian society.First,the temporal trends of this phenomenon are reconstructed using official statistics.The data reveal that,although still relatively rare,the dissolution of marriage in later life is expanding in Italy.The analysis of the period from 1974 to 2015 indicates a rise in the average age at separation,a higher percentage of spouses over 50 years on the total number of couples obtaining legal separation,and an increase in the proportion of Italian spouses separating after many years of marriage.Furthermore,data from the national survey“Family and Social Subjects”,conducted in 2016 by the Italian National Institute of Statistics,are utilized to explore the relationship between specific traits of those who separated and their tendency to dissolve marriages before or after the age of 50.The data suggest that individuals with characteristics such as lower educational attainment,residence in the South and Islands,and adherence to more traditional family models are more likely to experience separation in later life. 展开更多
关键词 marital dissolution later life gray divorce social inequality ITALY
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应力-渗流-溶蚀耦合作用下三维岩石裂隙渗透特性数值计算研究
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作者 申林方 吕倩文 +3 位作者 刘文连 张家明 杨鸿忠 李泽 《岩土工程学报》 北大核心 2025年第2期428-437,共10页
基于格子Boltzmann方法采用双分布函数分别模拟渗流速度场与溶质浓度场的演化过程,建立了三维岩石裂隙应力-渗流-溶蚀耦合作用机制的数值计算模型,并讨论了渗流流速、法向应力、溶蚀反应速率等因素对裂隙渗透特性演化规律的影响。结果表... 基于格子Boltzmann方法采用双分布函数分别模拟渗流速度场与溶质浓度场的演化过程,建立了三维岩石裂隙应力-渗流-溶蚀耦合作用机制的数值计算模型,并讨论了渗流流速、法向应力、溶蚀反应速率等因素对裂隙渗透特性演化规律的影响。结果表明:在渗流流速较低时,壁面溶蚀出来的离子得不到及时输运,使得出口处浓度较高溶蚀速度慢,裂隙结构呈“喇叭口”状。增大法向应力会减小裂隙开度,减慢溶质的运移速率,使得裂隙出口处的溶蚀速率显著降低,从而限制了其渗透率的发展。当壁面溶蚀反应速率较小时,裂隙渗透率呈持续缓慢增长的状态;随着溶蚀反应速率增加,出口处的溶蚀量会明显小于入口处,导致出口处壁面发生显著溶蚀之前,裂隙渗透率发展缓慢,此后渗透率便呈急速突变增长趋势。研究成果能够为酸蚀作用下岩石裂隙渗透能力的定量评价提供重要理论支撑。 展开更多
关键词 岩石裂隙 应力-渗流-溶蚀耦合 渗透特性 格子BOLTZMANN方法 数值计算
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Anodic dissolution behavior of zirconium in Bu_4~nNBr-containing isopropanol solution
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作者 杨喜云 黄海强 杨声海 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2016年第10期2738-2745,共8页
Anodic dissolutionbehaviorof zirconium inBu^n 4NBr-contaningisopropanol solution was investigated using cyclic voltammetry, linear sweep voltammetry and chronoamperometry, complemented with a scanning electron microsc... Anodic dissolutionbehaviorof zirconium inBu^n 4NBr-contaningisopropanol solution was investigated using cyclic voltammetry, linear sweep voltammetry and chronoamperometry, complemented with a scanning electron microscope (SEM).The voltammograms did not exhibit active dissolutionuntil the breakdown of passive layer induced by aggressive bromide anions.SEM images confirmed the existence of pits on zirconium surface.The depth and breadth of pits were intensified with increasing potential. The pitting potentialshifted negatively as either temperature orBu^n 4NBr concentration was increased, while it increased with increasing scan rate.The corrosion current density increased with increasing temperature. The apparent activation energyof anodic dissolutionofzirconiumwas 21.88kJ/mol. The chronoamperometry revealed that increasingBu^n 4NBrconcentration shortened the incubation time for passivity breakdown and accelerated the pit nucleation and growth. The experimental results were helpfulto obtain the optimum conditions for electrosynthesis of zirconium isopropoxide. 展开更多
关键词 ZIRCONIUM anodic dissolution pitting corrosion ISOPROPANOL tetrabutylammonium bromide
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In vitro Dissolution and Pharmacokinetics in Beagle Dogs of a Self-Emulsifying Formulation of Tretinoin
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作者 全东琴 徐贵霞 《Journal of Chinese Pharmaceutical Sciences》 CAS 2005年第2期105-109,共5页
Aim In vitro dissolution test and pharmacokinetics in beagle dogs wereconducted to assess the formulation of tretinoin in self-emulsifying systems. Methods Theconcentrations of tretinoin were determined by HPLC. A cro... Aim In vitro dissolution test and pharmacokinetics in beagle dogs wereconducted to assess the formulation of tretinoin in self-emulsifying systems. Methods Theconcentrations of tretinoin were determined by HPLC. A crossover study was performed in four fastingbeagle dogs with the formulation of self-emulsifying systems and commercial capsules. Results Theresults showed that the dissolution rate in 15 min of tretinoin in self-emulsifying systems washigher than 80% while that of the commercial capsules was lower than 5% . The area under the plasmaconcentration-time curve (AUC) of the self-emulsifying formulation was significantly higher andC_(max) was approximately two times greater than those of commercial capsule, respectively, Inaddition, the time taken to reach peak was shorter (2 h to 1.25 h) for self-emulsifying formulationof tretinoin. Conclusion The self-emulsifying drug delivery systems.can significantly increasetretinoin in vitro dissolution and in vivo absorption. 展开更多
关键词 self-emulsifying systems TRETINOIN BIOAVAILABILITY dissolution
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基于TGA-IST-GC-MS协同TGA和GC-MS评价香料的热稳定性及香气释放特征
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作者 朱龙杰 王蕙婷 +6 位作者 吴昌健 张华 朱君 叶远青 曹毅 殷志琦 朱怀远 《食品科学》 北大核心 2025年第4期201-208,共8页
为更好地评估香料的热稳定性,提升香料的使用价值,通过热重分析-样品存储接口-气相色谱-质谱(thermogravimetric analysis-sample storage interface-gas chromatography-mass spectrometry,TGA-IST-GC-MS)联用法辅以TGA和GC-MS建立香... 为更好地评估香料的热稳定性,提升香料的使用价值,通过热重分析-样品存储接口-气相色谱-质谱(thermogravimetric analysis-sample storage interface-gas chromatography-mass spectrometry,TGA-IST-GC-MS)联用法辅以TGA和GC-MS建立香料热稳定性的统一评价方法。首先根据香料的挥发特性,利用TGA获得最佳进样温度,然后使用GC-MS和TGA-IST-GC-MS在不同体系下分别获得常规GC-MS图和TGA-GC-MS图,通过2种色谱图对比计算得到香料热稳定性的稳定度、裂解度和碎裂度3个重要指标,最后再依据热稳定性对香料加热前后的香气变化进行考察。结果表明:以香料挥发时的最大质量损失速率峰温度作为TGA-IST-GC-MS的最佳进样温度,方法具有较高的响应强度和较好的重复性;通过2种GC-MS图的对比,有效降低了香料基质背景的影响,提高了方法的准确性,使其对单体香料和多组分天然香料都具有较好的适用性;依据热稳定性的3个指标,可进一步掌握香料受热反应时的裂解强度和新裂解产物的生成量,对香气评价具有较好的实用性和指导性。 展开更多
关键词 热重分析-样品存储接口-气相色谱-质谱 香料 热稳定性 裂解产物 香气评价
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基于顶空-固相微萃取-气相色谱-质谱和顶空-气相色谱-离子迁移谱技术结合化学计量法分析芜菁冻干片挥发性成分
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作者 岳丽 张英仙 +4 位作者 祖力皮牙·买买提 王佳敏 毛红艳 于明 热依拉木·海力力 《食品与发酵工业》 北大核心 2025年第2期300-310,共11页
为探究不同品种芜菁冻干片中挥发性有机物(volatile organic compounds,VOCs)的差异,采用顶空-固相微萃取-气相色谱-质谱(headspace solid phase microextraction gas chromatography-mass spectrometry,HS-SPME-GC-MS)和顶空-气相色谱... 为探究不同品种芜菁冻干片中挥发性有机物(volatile organic compounds,VOCs)的差异,采用顶空-固相微萃取-气相色谱-质谱(headspace solid phase microextraction gas chromatography-mass spectrometry,HS-SPME-GC-MS)和顶空-气相色谱-离子迁移谱(headspace gas chromatography-ion mobility spectrometry,HS-GC-IMS)对紫色、黄色和白色3种芜菁冻干片的VOCs进行分析,并结合主成分分析(principal component analysis,PCA)和偏最小二乘判别法(partial least squares-discriminant analysis,PLS-DA)等化学计量法探究不同品种芜菁冻干片挥发性成分的差异。结果表明,通过HS-SPME-GC-MS共解析出96种VOCs,包括醛类、醇类、酮类、含硫化合物、酯类、酸类等化合物,其中含硫化合物和酯类为芜菁冻干片中相对含量最高的化合物种类;HS-GC-IMS共解析出94种VOCs,包括醛类、酯类、酮类及含硫化合物等挥发性成分。HS-SPME-GC-MS和HS-GC-IMS检出的挥发性物质种类和含量存在差异,共有VOCs有15种,二者结果互为补充,结合使用可以较全面系统地表征芜菁冻干片的挥发性成分。PCA和PLS-DA结果表明,2种方法均能够有效区分3种芜菁冻干片。通过变量投影重要度分别筛选了59种和23种差异VOCs,该结果可为芜菁冻干片VOCs的差异分析提供参考方法。 展开更多
关键词 芜菁冻干片 挥发性有机物 顶空-固相微萃取-气相色谱-质谱 顶空-气相色谱-离子迁移谱 变量投影重要度
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福建省1990-2019年慢性肾脏病疾病负担的时间趋势和归因危险因素分析
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作者 林修全 林晓茹 +7 位作者 杨成琳 王新钰 欧阳江 管晴 黄少芬 尹艳榕 梁栋 钟文玲 《中华流行病学杂志》 北大核心 2025年第1期57-64,共8页
目的掌握1990-2019年福建省慢性肾脏病(CKD)疾病负担及其归因危险因素。方法根据2019年全球疾病负担研究的方法,计算1990-2019年福建省CKD的发病率、死亡率和伤残调整寿命年(DALY)。采用年龄-时期-队列模型估计年龄、时期和队列对年龄... 目的掌握1990-2019年福建省慢性肾脏病(CKD)疾病负担及其归因危险因素。方法根据2019年全球疾病负担研究的方法,计算1990-2019年福建省CKD的发病率、死亡率和伤残调整寿命年(DALY)。采用年龄-时期-队列模型估计年龄、时期和队列对年龄标化发病率(ASIR)、年龄标化死亡率(ASMR)和年龄标化DALY率(ASDR)的影响。通过比较风险评估理论计算潜在危险因素的可归因DALY。结果2019年福建省ASIR高于全国平均水平,1990-2019年呈上升趋势。1990-2019年ASMR和ASDR均呈下降趋势。2019年福建省CKD的ASIR女性高于男性,ASMR和ASDR男性高于女性。年龄-时期-队列分析结果显示,福建省CKD的ASIR、ASMR和ASDR随年龄的增长而增加,ASIR的时期效应随年份的增加呈先下降后上升趋势,而ASMR和ASDR的时期效应呈波动趋势,ASIR的队列效应呈上升趋势,ASMR和ASDR的队列效应均呈先平稳后下降趋势。与1990年相比,2019年福建省CKD除归因于高BMI和高温的ASDR增加外,其余可归因危险因素的ASDR均下降,但归因于高钠饮食的ASDR仍高于全球平均水平。结论福建省CKD疾病负担仍较重,可通过改变高钠饮食、高BMI等归因危险因素来减轻福建省CKD疾病负担。 展开更多
关键词 慢性肾脏病 疾病负担 年龄-时期-队列模型 危险因素
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斜冠状位最大密度投影及容积再现重建CT门静脉血管成像用于诊断脾/胃-左肾分流
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作者 邓琳 梁萍 +2 位作者 黄仲奎 朱定娇 陈更瑞 《中国介入影像与治疗学》 北大核心 2025年第1期32-36,共5页
目的 探讨斜冠状位最大密度投影(OC-MIP)及容积再现(VR)重建CT门静脉血管成像(CTPA)用于诊断脾/胃-左肾分流(S/sLKS)的价值。方法 回顾性收集接受TIPS治疗的62例肝硬化失代偿期患者,基于TIPS前门静脉期增强CT以OC-MIP和VR技术重建获得CT... 目的 探讨斜冠状位最大密度投影(OC-MIP)及容积再现(VR)重建CT门静脉血管成像(CTPA)用于诊断脾/胃-左肾分流(S/sLKS)的价值。方法 回顾性收集接受TIPS治疗的62例肝硬化失代偿期患者,基于TIPS前门静脉期增强CT以OC-MIP和VR技术重建获得CTPA,以之诊断S/sLKS并进行分型。以TIPS中数字减影血管造影(DSA)所见为标准,评估OC-MIP和VR图像诊断S/sLKS的效能及其结果与DSA结果的一致性。结果 DSA显示,62例中,14例(14/62,22.58%)存在S/sLKS、48例(48/62,77.42%)未见S/sLKS。OC-MIP及VR图诊断S/sLKS的敏感度、特异度、准确率均一致,分别为92.86%(13/14)、95.83%(46/48)、95.16%(59/62);其诊断结果与DSA的一致性均较高(Kappa均0.865)。14例S/sLKS中,DSA显示1例(1/14,7.14%)为脾-肾分流(SRS),1例(1/14,7.14%)为胃-肾分流(GRS),7例(7/14,50.00%)为脾-胃-肾分流(SsRS),4例(4/14,28.57%)SRS与GRS并存(SRS&GRS),1例(1/14,7.14%)为SRS&GRS+SRS双分流道。1例GRS OC-MIP及VR图均未显示分流道;4例SRS&GRS中,2例DSA显示各1支脾静脉(SPV)属支较细小,而OC-MIP及VR图均未显示;其余病例OC-MIP及VR图所示来源静脉均与DSA一致。结论 OC-MIP及VR重建CTPA对诊断S/sLKS具有较高临床价值。 展开更多
关键词 门静脉 CT血管成像 -肾分流 -肾分流
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见光诱导催化合成3,4-二氢异喹啉-1(2H)-酮及其衍生物
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作者 康建军 王津 陈艳 《化学研究与应用》 北大核心 2025年第1期230-236,共7页
建立了一种在温和条件下,用可见光催化合成一系列3,4-二氢异喹啉-1(2H)-酮及其衍生物的方法。该方法在室温条件下,以2-烯丙基-N-甲氧基苯甲酰胺为模板底物,以碘化钾作为光催化剂,25 W 460 nm的蓝色LED灯照射下,合成一系列3,4-二氢异喹啉... 建立了一种在温和条件下,用可见光催化合成一系列3,4-二氢异喹啉-1(2H)-酮及其衍生物的方法。该方法在室温条件下,以2-烯丙基-N-甲氧基苯甲酰胺为模板底物,以碘化钾作为光催化剂,25 W 460 nm的蓝色LED灯照射下,合成一系列3,4-二氢异喹啉-1(2H)-酮衍生物,最高产率可达到83%。该合成路径具有底物适用范围广、经济实用等特点,为3,4-二氢异喹啉-1(2H)-酮衍生物合成提供了一种经济简便的方法。 展开更多
关键词 可见光 2-烯丙基-N-甲氧基苯甲酰胺 3 4-二氢异喹啉-1(2H)- 异喹啉酮
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血清sIL-2R联合TNF-α、IgG、IgA对多发性骨髓瘤患者复发的预测价值
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作者 林萍 张雅兰 +1 位作者 谢若腾 张学亚 《中国实验血液学杂志》 北大核心 2025年第1期150-156,共7页
目的:探讨血清可溶性白细胞介素-2受体(soluble interleukin-2 receptor,sIL-2R)、肿瘤坏死因子-α(TNF-α)、IgG、IgA对多发性骨髓瘤(multiple myeloma,MM)复发的预测价值。方法:选取2017年1月-2019年3月在本院初诊且治疗的MM患者108例... 目的:探讨血清可溶性白细胞介素-2受体(soluble interleukin-2 receptor,sIL-2R)、肿瘤坏死因子-α(TNF-α)、IgG、IgA对多发性骨髓瘤(multiple myeloma,MM)复发的预测价值。方法:选取2017年1月-2019年3月在本院初诊且治疗的MM患者108例,最终确定符合诊断标准且有完整随访资料的72例患者作为研究对象,以MM复发为研究终点事件,随访至终点事件的发生或本研究随访截止日期。根据是否复发,将MM分为复发组(RG)和非复发组(NRG)。在初诊时和随访后(终点事件的发生或研究终止时)分别采集患者静脉血,酶联免疫吸附测定法(ELISA)检测患者血清中sIL-2R和TNF-α水平;自动免疫分析仪检测患者血清中IgG、IgA水平;比较两组之间各因子表达水平的差异,并分析初诊时和随访后sIL-2R与TNF-α、IgG、IgA之间的相关性。同时在治疗完全缓解时采集患者静脉血,测定血清中sIL-2R水平,比较初诊时、完全缓解时和复发时sIL-2R表达水平的差异。采用受试者工作特征(ROC)曲线判断血清sIL-2R、TNF-α、IgG、IgA的最佳截断值,并根据曲线下面积(AUC)分析sIL-2R、TNF-α、IgG、IgA在MM复发中的预测价值。结果:MM患者初诊时和复发时血清sIL-2R水平均明显高于完全缓解时(P<0.05)。复发组初诊时的血红蛋白(Hb)含量低于未复发组,β2-微球蛋白(β2-MG)含量高于未复发组(P<0.001),两组间的其他临床参数无显著差异(P>0.05)。复发组初诊时和随访后的sIL-2R、TNF-α、IgG、IgA水平均明显高于未复发组(P<0.05),sIL-2R与TNF-α、IgG和IgA在初诊时和随访后均存在显著正相关(P<0.001)。ROC曲线分析结果显示,初诊时sIL-2R、TNF-α、IgG和IgA预测MM的AUC分别为0.919、0.850、0.766和0.795,随访后预测MM的AUC分别为0.890、0.815、0.760和0.794(P<0.001)。结论:血清sIL-2R对MM复发的预测价值最高,可在特定的时间检测TNF-α、IgG和IgA水平来推断sIL-2R水平的变化,从而评估患者的预后。 展开更多
关键词 可溶性白细胞介素-2受体 肿瘤坏死因子-α IGG IGA 多发性骨髓瘤 复发
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气相色谱-串联质谱同时测定白酒中20种吡嗪类化合物
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作者 王娜 沈毅 +6 位作者 庄园 程伟 罗森 张亚东 刘子轩 刘冰 高红波 《食品科学》 北大核心 2025年第5期30-37,共8页
本研究采用直接进样结合气相色谱-串联质谱技术建立测定白酒中20种吡嗪类化合物的方法,并对10种香型不同品牌白酒中的吡嗪类化合物进行测定。该方法在0.01~10.00 mg/L的质量浓度范围内具有良好的线性关系,决定系数R^(2)在0.998 3~0.999 ... 本研究采用直接进样结合气相色谱-串联质谱技术建立测定白酒中20种吡嗪类化合物的方法,并对10种香型不同品牌白酒中的吡嗪类化合物进行测定。该方法在0.01~10.00 mg/L的质量浓度范围内具有良好的线性关系,决定系数R^(2)在0.998 3~0.999 7的范围内,检出限在0.16×10^(-3)~3.25×10^(-3) mg/L范围内,不同浓度条件下的加标回收率在81.26%~113.13%之间,日内日间相对标准偏差在1.42%~4.98%之间。10种香型白酒中吡嗪类化合物的定量分析结果表明,吡嗪类化合物在酱香型白酒中含量最高,质量浓度范围为2.63~16.88 mg/L,其次是芝麻香型和兼香型。该方法与气相色谱-质谱法相比具有更高的准确度及灵敏度,适用于不同香型白酒中吡嗪类化合物的分析。 展开更多
关键词 气相色谱-串联质谱 白酒 吡嗪类化合物 气相色谱-质谱
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井筒-射孔-裂缝全耦合双暂堵压裂实验装置研发与应用
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作者 郭天魁 郝彤 +6 位作者 张跃龙 陈铭 曲占庆 王文宇 吕明锟 杨仁杰 戴海静 《实验技术与管理》 北大核心 2025年第1期161-168,共8页
为将基于缝间(段内)射孔暂堵球与缝内暂堵剂的“缝间-缝内”暂堵压裂技术转化为实验教学内容,该文设计了井筒-射孔-裂缝全耦合暂堵压裂物理模拟实验装置。装置能够设置泵注压力、排量、射孔参数、裂缝粗糙程度、裂缝宽度等实验条件,开... 为将基于缝间(段内)射孔暂堵球与缝内暂堵剂的“缝间-缝内”暂堵压裂技术转化为实验教学内容,该文设计了井筒-射孔-裂缝全耦合暂堵压裂物理模拟实验装置。装置能够设置泵注压力、排量、射孔参数、裂缝粗糙程度、裂缝宽度等实验条件,开展非常规储层暂堵压裂物理模拟实验,并通过进出口流量监测、多点测压、可视化图像处理等方式对实验结果进行精细化表征,对段内暂堵与缝内暂堵两种压裂辅助工艺进行评价优化。该实验装置占地面积小、操作简便安全、功能丰富,是储层改造技术创新实践平台的重要组成部分。 展开更多
关键词 储层改造 实验装置 井筒-射孔-裂缝全耦合 暂堵压裂 暂堵材料性能评价
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热-力耦合作用下乏燃料剪切机运动副干摩擦行为研究
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作者 杨贺 董建鹏 +2 位作者 高峰 高山 谭傲霜 《原子能科学技术》 北大核心 2025年第2期503-512,共10页
极端工况下乏燃料剪切机不锈钢滚轮运动副会出现卡死现象,滚动摩擦变为滑动摩擦,加之高辐照工况下难以润滑,导致轮轨运动副磨损严重。本文通过对经典Archard模型进行修正,建立了不锈钢干摩擦磨损的热-力耦合模型。对比试验表明,磨损预... 极端工况下乏燃料剪切机不锈钢滚轮运动副会出现卡死现象,滚动摩擦变为滑动摩擦,加之高辐照工况下难以润滑,导致轮轨运动副磨损严重。本文通过对经典Archard模型进行修正,建立了不锈钢干摩擦磨损的热-力耦合模型。对比试验表明,磨损预测的最大相对误差为9.34%,验证了所建立模型的有效性。利用本文所建模型研究了极限滑动工况下剪切滑车滚轮的摩擦行为。结果表明,随着滑动距离的增加,温度和Mises应力都呈先下降后上升的趋势,且对接触区域的影响范围逐渐扩大。本研究得到了滚轮磨损深度与滑动距离之间的定量映射规律,为提高乏燃料剪切机的可靠性提供理论依据。 展开更多
关键词 不锈钢运动副 干摩擦 Archard模型 --磨损完全耦合
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压水堆国产SA-508-Ⅲ-1钢环境影响疲劳试验研究和预测模型开发
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作者 沈睿 刘畅 +1 位作者 唐力晨 王秉熙 《原子能科学技术》 北大核心 2025年第1期151-159,共9页
对压水堆核电厂一回路设备用国产SA-508 Gr.3 Cl.1低合金钢(简称SA-508-Ⅲ-1钢)进行室温和320℃空气环境,以及模拟压水堆一回路水环境下的疲劳性能试验研究,获得国产SA-508-Ⅲ-1钢在空气环境下的疲劳寿命最佳拟合曲线(平均曲线)。在此... 对压水堆核电厂一回路设备用国产SA-508 Gr.3 Cl.1低合金钢(简称SA-508-Ⅲ-1钢)进行室温和320℃空气环境,以及模拟压水堆一回路水环境下的疲劳性能试验研究,获得国产SA-508-Ⅲ-1钢在空气环境下的疲劳寿命最佳拟合曲线(平均曲线)。在此基础上,对影响国产SA-508-Ⅲ-1钢在压水堆核电厂一回路水环境下疲劳性能的应变速率、温度和溶解氧含量等参数的影响规律进行研究,获得各影响参数的影响函数方程。基于获得的各影响参数的函数方程,建立国产SA-508-Ⅲ-1钢的环境影响疲劳修正因子F_(en)预测模型。本文获得的压水堆核电厂一回路水环境下国产SA-508-Ⅲ-1钢的疲劳寿命都位于95%置信度限值(10^(±2σ))范围内,验证了本文预测模型的有效性。同时,本文获得的压水堆核电厂一回路水环境下国产SA-508-Ⅲ-1钢的疲劳寿命与美国阿贡国家实验室(ANL)模型所预测的寿命相比,也都位于95%置信度限值(10^(±2σ))范围内,说明ANL模型可用于国产SA-508-Ⅲ-1钢的疲劳寿命预测。本文获得的国产SA-508-Ⅲ-1钢的环境影响疲劳预测模型与ANL模型相比,更适用于国产SA-508-Ⅲ-1钢的寿命预测,为国内第3代核电厂一回路设备考虑压水堆一回路水环境影响的疲劳设计提供参考。 展开更多
关键词 压水堆核电厂 SA-508--1钢 环境影响疲劳 F_(en) 预测模型
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血清Tim-3、Galectin-9对重度创伤性脑损伤患者并发急性呼吸窘迫综合征的预测价值
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作者 曹建良 吴钊 +2 位作者 张唐娟 兰超 田琦 《中华神经外科疾病研究杂志》 CAS 2025年第1期48-52,共5页
目的探讨血清T细胞免疫球蛋白黏蛋白分子-3(Tim-3)、半乳糖凝集素-9(Galectin-9)对重度创伤性脑损伤(TBI)患者并发急性呼吸窘迫综合征(ARDS)的预测价值。方法选取2020年1月至2023年12月郑州大学第一附属医院收治的180例重度TBI患者作为... 目的探讨血清T细胞免疫球蛋白黏蛋白分子-3(Tim-3)、半乳糖凝集素-9(Galectin-9)对重度创伤性脑损伤(TBI)患者并发急性呼吸窘迫综合征(ARDS)的预测价值。方法选取2020年1月至2023年12月郑州大学第一附属医院收治的180例重度TBI患者作为研究对象,根据受伤后1周内是否发生ARDS分为ARDS组(n=62)和非ARDS组(n=118)。比较两组患者血清Tim-3、Galectin-9水平;采用受试者工作特性(ROC)曲线评估血清Tim-3、Galectin-9对重度TBI患者并发ARDS的预测价值;采用二分类Logistic逐步回归分析探讨重度TBI患者并发ARDS的影响因素。结果ARDS组血清Tim-3、Galectin-9水平高于非ARDS组(P<0.05)。血清Tim-3、Galectin-9及二者联合预测重度TBI患者并发ARDS的曲线下面积(AUC)(95%CI)分别为0.786(0.716-0.855)、0.735(0.652-0.818)、0.835(0.775-0.895),截断值分别为264.24 ng/mL、8.06 ng/mL,特异度分别为0.831、0.788、0.763,灵敏度分别为0.613、0.626、0.742。ARDS组年龄≥60岁、合并休克、机械通气时间≥5d、ICU住院时间≥14d所占的比例均大于非ARDS组,入院时格拉斯哥昏迷量表(GCS)评分、氧合指数(OI)低于非ARDS组,降钙素原(PCT)水平高于非ARDS组(P<0.05)。入院时GCS评分低(OR=0.727,95%CI:0.543-0.973)、OI低(OR=0.957,95%CI:0.932-0.983)、合并休克(OR=9.259,95%CI:3.183-26.937)、Tim-3水平升高(OR=7.110,95%CI:2.738-18.468)、Galectin-9水平升高(OR=7.063,95%CI:2.736-18.230)是重度TBI患者并发ARDS的独立危险因素(P<0.05)。结论血清Tim-3、Galectin-9水平升高与重度TBI患者并发ARDS密切相关,两指标可作为预测重度TBI患者并发ARDS的生物标记物。 展开更多
关键词 T细胞免疫球蛋白黏蛋白分子-3 半乳糖凝集素-9 创伤性脑损伤 急性呼吸窘迫综合征
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