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An observed nocturnal ozone transport event in the Sichuan Basin,Southwestern China

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Journal of Environmental Sciences 2024年第4期138卷 10-18页

作者： Ruyue guo Guangming Shi dan Zhang Yang Chen Chao Peng Chongzhi Zhai Fumo Yang Department of Environmental Science and Engineering Sichuan UniversityChengdu 610065China College of Carbon Neutrality Future Technology Sichuan UniversityChengdu 610065China National Engineering Research Center on Flue Gas Desulfurization Chengdu 610065China Chongqing Academy of Eco-Environmental Science Chongqing 401147China Research Center for Atmospheric Environment Chongqing Institute of Green and Intelligent TechnologyChinese Academy of SciencesChongqing 400714China Key Laboratory for Urban Atmospheric Environment Integrated Observation&Pollution Prevention and Control of Chongqing Chongqing 401147China

The ozone(O_(3))pollution in China drew lots of attention in recent years,and the Sichuan Basin(SCB)was one of the regions confronting worsening O_(3)pollution *** previous studies have shown that regional transport is an important contributor to O_(3)***,very few features of the O_(3)profile during transport have been reported,especially in the border regions between different administrative *** this study,we conducted tethered balloon soundings in SCB during the summer of 2020 and captured a nocturnal O_(3)transport event during the ***,the O_(3)transport occurred in the bottom of the residual layer,between 200 and 500 m above ground ***,the transport pathway was directed from southeast to northwest based on the analysis of the wind field and air mass *** effect of transport in the residual layer on the surface O_(3)concentration was related to the spatial distribution of O_(3).For cities with high O_(3)concentrations in the upwind region,the transport process would bring clean air masses and abate *** downwind lightly polluted cities,the transport process would slow down the decreasing or even increase the surface O_(3)concentration during the *** provided observational facts on the profile features of a transboundary O_(3)transport event between two provincial administrative divisions,which implicated the importance of joint prevention and control ***,the sounding parameters were limited and the quantitative analysis was preliminary,more integrated,and thorough studies of this topic were called for in the future.

关键词： Ozone Sichuan basin Transport event Vertical profile

改良成人经口气管插管机械通气患者口腔护理方法及应用

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实用医院临床杂志 2024年第1期21卷 145-148页

作者：王丽贾平张勤郭丹阳蒲在春涂姣四川省医学科学院·四川省人民医院四川成都610072 电子科技大学医学院四川成都611731

目的探讨改良成人经口气管插管机械通气患者口腔护理方法的应用效果。方法便利抽样选取2021年1月1日至2021年12月30日四川省人民医院神外监护室经口气管插管机械通气患者220例为对照组,口腔护理方法为冲洗+擦拭+吸痰管连接负压吸引;2022... 详细信息

目的探讨改良成人经口气管插管机械通气患者口腔护理方法的应用效果。方法便利抽样选取2021年1月1日至2021年12月30日四川省人民医院神外监护室经口气管插管机械通气患者220例为对照组,口腔护理方法为冲洗+擦拭+吸痰管连接负压吸引;2022年1月1日至2022年12月30日经口气管插管机械通气患者163例为观察组,口腔护理方法为擦拭+冲洗+吸唾管连接负压吸引。比较两组患者口腔异味发生率、口腔污垢残留、操作时口腔内污液溢出及吸唾管/吸痰管滑出情况、呼吸机相关性肺炎发生率。结果两组患者呼吸机相关性肺炎发生率比较差异无统计学意义(P>0.05);两组口腔异味发生率、口腔污垢残留、操作时口腔内污液溢出及吸唾管/吸痰管滑出、操作耗时等比较,差异有统计学意义(P<0.05);100%操作人员愿意选择观察组的吸唾管连接负压吸引口腔护理废液(P<0.05)。结论改良成人经口气管插管机械通气患者口腔护理方法,能提高口腔护理质量、提高患者舒适度,节约成本、提高工作效率,有一定的推广应用价值。

关键词：经口气管插管机械通气口腔护理吸唾管呼吸机相关性肺炎

Strengthening and control of second-phase particle precipitation in ferritic/austenitic/martensitic heat-resistant alloys:a review

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Journal of Iron and Steel Research International 2024年第1期31卷 3-23页

作者： Xue-cheng Peng Han-jie guo Xin-fang Zhang Yi-wa Luo Ye Sun Jing guo Rong-guang Yang Xiao-dan Zheng School of Metallurgical and Ecological Engineering University of Science and Technology Beijing(USTB)Beijing100083China Beijing Key Laboratory of Special Melting and Preparation of High-End Metal Materials University of Science and Technology Beijing(USTB)Beijing100083China Beijing Shougang Gitane New MATERIALS Co. Ltd.Beijing102206China

Heat-resistant alloys with excellent mechanical properties are widely used in various fields,and further improvement in their properties is essential to meet the requirements in new-generation advanced supercritical boilers,nuclear reactors,superheaters,and other new materials *** effectively enhance the comprehensive performance of heat-resistant alloys,second-phase particle strengthening has been widely studied,and in the face of different service envi-ronments of advanced heat-resistant steels,the selection of suitable second-phase particles is essential to maximize the performance of these *** this end,three major types of reinforcing phases in heat-resistant alloys such as carbides,rare earth oxides,and intermetallic compounds are summarized.A comparative analysis of the precipitation behavior of the reinforcing phases with different types as well as the risks and means of controlling their use in service,is *** parameters for the application of various types of second-phase particles in heat-resistant alloys are provided to support the design and preparation of new ultrahigh-performance heat-resistant alloys.

关键词： Heat-resistant alloy Second-phase particle Carbide Rare earth oxide Intermetallic compound Strengthening

LINC00475在多发性骨髓瘤中的表达与临床意义

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中国实验血液学杂志 2024年第3期32卷 789-793页

作者：卢玲郭丹洪乐旻蒋钰雯范洪明黄春群卢金凤陈洁徐宏慧黄红铭南通大学附属医院血液内科江苏南通226001

目的:探讨LINC00475在多发性骨髓瘤(MM)患者血清中的相对表达水平及临床意义。方法:用实时荧光定量PCR技术检测108例MM患者血清及RPMI 8226、NCI-H929、U266、OPM2、CAG这5个MM细胞系中LINC00475的表达情况,受试者工作特征曲线评估其对M... 详细信息

目的:探讨LINC00475在多发性骨髓瘤(MM)患者血清中的相对表达水平及临床意义。方法:用实时荧光定量PCR技术检测108例MM患者血清及RPMI 8226、NCI-H929、U266、OPM2、CAG这5个MM细胞系中LINC00475的表达情况,受试者工作特征曲线评估其对MM的诊断价值,并结合患者的临床资料分析LINC00475与患者临床特征的关系。结果:与健康对照组相比,MM患者血清及MM细胞系中LINC00475的表达明显上调(均P<0.05)。受试者工作特征曲线分析显示,LINC00475的最佳截断值为262.4,曲线下面积为0.924(95%CI:0.884-0.964),灵敏度83.3%,特异度91.7%,表明LINC00475在MM患者中具有良好的评估价值。与LINC00475低表达组的MM患者相比,高表达组的患者具有较高水平的β2-微球蛋白和胱抑素C(均P<0.05),但白蛋白水平较低(P<0.05)。与ISS分期Ⅰ期的MM患者相比,Ⅱ期和Ⅲ期患者LINC00475的表达水平均明显增高(均P<0.05)。结论:检测LINC00475的相对表达水平有助于区分MM患者和正常人群,其相对表达水平与MM患者的β2-微球蛋白、白蛋白、ISS分期等预后指标相关。

关键词：多发性骨髓瘤 LINC00475 长链非编码RNA

In situ modification of heavy oil catalyzed by nanosized metal-organic framework at mild temperature and its mechanism

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Chinese Journal of Chemical Engineering 2024年第3期67卷 166-173页

作者： Li Wang Ji-Xiang guo Rui-Ying Xiong Chen-Hao Gao Xiao-Jun Zhang dan Luo The Unconventional Oil and Gas Institute China University of Petroleum-BeijingBeijing 102200China Beijing Institute of Nanoenergy and Nanosystems Chinese Academy of SciencesBeijing 101400China

Two catalysts, nano-sized cobalt-metal-organic framework(Co-MOF) and nickel(Ni)-MOF, were successfully prepared by the modification method. Tetralin(C10H12) was used as the hydrogen donor for the catalytic cracking and hydrogenation modification study of the dehydrated crude oil from the Shengli Oilfield. The optimal reaction conditions were determined through orthogonal experiments, and the components of the crude oil and modified oil samples were analyzed. The results revealed that the nanoMOF catalysts were successfully prepared and exhibited high catalytic activity. They could catalyze the cracking of large molecules in heavy oil at mild temperatures(<300°C), leading to the decomposition of the hydrogen donor. When the mass fraction of the catalyst was 0.2%, the mass fraction of the hydrogen donor was 1%, and the reaction temperature was 280°C, the Ni-MOF showed the best catalytic viscosity reduction effect. It could reduce the viscosity of heavy oil at 50°C from 15761.9 m Pa.s to 1266.2 m Pa.s,with a viscosity reduction rate of 91.97%. The modification effect of Co-MOF was the next best, which could reduce the viscosity of heavy oil to 2500.1 m Pa.s with a viscosity reduction rate of 84.14%. Molecular dynamics simulations revealed a strong interaction force between the MOF surface and asphaltene molecules. In the process of heavy-oil catalytic hydrogenation, the nano-MOF catalyst exhibited high catalytic activity. On the one hand, the empty d orbitals outside the metal atoms in the catalyst could polarize the carbon atoms in the organic matter, accelerating the breaking of long chains. On the other hand, the metal atoms in the catalyst could bond with the carbon σ bonds, breaking the carbon-carbon bonds. This disrupted the structure of the recombined components in the crude oil, irreversibly reducing the viscosity of the heavy oil and improving its fluidity.

关键词： Nano-sized MOF Petroleum Viscosity reduction Catalyst Nanomaterials

Film forming behavior in thin film lubrication at high speeds

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Friction 2018年第2期6卷 156-163页

作者： He LIANG dan guo Jianbin LUO State Key Laboratory of Tribology Tsinghua University

The film forming condition may transit into thin film lubrication(TFL) at high speeds when it is under severe starvation. Central film thicknesses and film thickness profiles are obtained via a technique of relative optical interference intensity. These profiles show a critical film thickness lower than which the absolute values of the film thickness gradient against speed or time decrease. It is possible to be in the thin film lubrication mode under such conditions. The high speed flow drives the lubricant molecules to rearrange in TFL and critical film thickness higher than 100 nm is achieved. The viscosity is one of the main factors controlling the decreasing rate and the critical film thickness. This paper is designed to investigate the thin film lubrication behavior at high speeds.

关键词： thin film lubrication thin EHL film high speeds starvation

Bounding the sum of powers of the Laplacian eigenvaluesof graphs

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Applied Mathematics(A Journal of Chinese Universities) 2011年第2期26卷 142-150页

作者： CHEN Xiao-dan QIAN Jian-guo School of Mathematical Sciences Xiamen University Xiamen 361005 Fujian P.R. China

For a non-zero real number α, let sα（G） denote the sum of the αth power of thenon-zero Laplacian eigenvalues of a graph G. In this paper, we establish a connection betweensα（G） and the first Zagreb index in which the H¨older’s inequality plays a key role. By usingthis result, we present a lot of bounds of sα（G） for a connected （molecular） graph G in terms ofits number of vertices （atoms） and edges （bonds）. We also present other two bounds for sα（G）in terms of connectivity and chromatic number respectively, which generalize those results ofZhou and Trinajsti′c for the Kirchho？ index [B Zhou, N Trinajsti′c. A note on Kirchho？ index,Chem. Phys. Lett., 2008, 455： 120-123].

关键词： Laplacian eigenvalues the first Zagreb index Kirchhoff index connectivity chromatic number.

Double-confined nanoheterostructure Sb/Sb_(2)S_(3)@Ti_(3)C_(2)T_(x)@C toward ultra-stable Li-/Na-ion batteries

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Rare Metals 2024年第5期43卷 2067-2079页

作者： dan Wang Qun Ma Huan He Zhi-Yuan Wang Run-guo Zheng Hong-Yu Sun Yan-guo Liu Chun-Li Liu School of Materials Science and Engineering Northeastern UniversityShenyang110819China School of Resources and Materials Northeastern University at QinhuangdaoQinhuangdao 066004China Key Laboratory of Dielectric and Electrolyte Functional Material Hebei Province Qinhuangdao 066004China Department of Physics and Oxide Research Center Hankuk University of Foreign StudiesYongin 17035Korea

Antimony-based materials with high capacities and moderate potentials are promising anodes for lithium-/-sodium-ion ***,their tremendous volume expansion and inferior conductivity lead to poor structural stability and sluggish reaction ***,a doubleconfined nanoheterostructure Sb/Sb_(2)S_(3)@Ti_(3)C_(2)T_(x)@C has been fabricated through a solvothermal method followed by low-temperature heat *** dual protection of“MXene”and“carbon”can better accommodate the volume expansion of Sb/Sb_(2)S_(3).The strong covalent bond(Ti-S,Ti-O-Sb,C-O-Sb)can firmly integrate Sb-based material with Ti_(3)C_(2)T_(x)and carbon,which significantly improves the structure *** addition,the carbon layer can restrain the oxidation of MXenes,and the nano-Sb/Sb_(2)S_(3)can facilitate electron/ion transport and suppress the restacking of *** heterogeneous interface between Sb and Sb_(2)S_(3)can further promote interfacial charge *** MXene-Sb/Sb_(2)S_(3)@C-1 with the optimal Sb content shows high specific capacities,comparable rate properties and ultra-stable cycling performances(250 m Ah·g^(-1)after 2500 cycles at 1 A·g^(-1)for sodium-ion batteries).Ex situ X-ray diffractometer(XRD)test reveals the storage mechanism including the conversion and alloying process of MXene-Sb/Sb_(2)S_(3)@*** voltammetry(CV)test results demonstrate that the pseudocapacitance behavior is dominant in MXene-Sb/Sb_(2)S_(3)@C-1,especially at large *** design paves the way for exploring high-performance alloy-based/conversion-type anode for energy storage devices.

关键词： Sb/Sb_(2)S_(3) MXene Carbon Anode Lithium-ion batteries Sodium-ion batteries

Boosting high-rate Li-ion storage properties by La(Ⅲ)ion doping in spinel(Co_(0.2)Cr_(0.2)Fe_(0.2)Mn_(0.2)Ni_(0.2))_(3)O_(4)high-entropy oxide anode

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Journal of Advanced Ceramics 2024年第6期13卷 769-779页

作者： Shijie Chen Mengfan Bao Yanggang Jia Pengpeng Wang dan Wei Yuhuan guo Jie Tan Aiqin Mao Advanced Ceramics Research Center School of Materials Science and EngineeringAnhui University of TechnologyMa’anshan 243032China Key Laboratory of Green Fabrication and Surface Technology of Advanced Metal Materials(Anhui University of Technology) Ministry of EducationMa’anshan 243032China

The present work aims to create lattice distortion and optimize the surface oxygen vacancy(OV)concentration in a model spinel(Co_(0.2)Cr_(0.2)Fe_(0.2)Mn_(0.2)Ni_(0.2))_(3)O_(4)high-entropy oxide(HEO)through a heteroatom La^(3+)doping *** demonstrated,La^(3+)with a large radius can be doped successfully into the spinel lattice of(Co_(0.2)Cr_(0.2)Fe_(0.2)Mn_(0.2)Ni_(0.2))_(3)O_(4),thereby not only causing lattice distortion to increase oxygen vacancies but also refining crystalline grains and improving the specific *** with the(Co_(0.2)Cr_(0.2)Fe_(0.2)Mn_(0.2)Ni_(0.2))_(3)O_(4)anode,the(La_(0.01)CoCrFeMnNi)_(3/5.01)O_(4) anode with moderate doping exhibits excellent cycling performance(1228 mAh·g^(−1)after 400 cycles at 0.2 A·g^(−1))and yields an increase of 75%rate capability at 3 A·g^(−1)(420 mAh·g^(−1)at 3 A·g^(−1)).The desirable kinetic transport of electrons and diffusion of Li+within the moderately La^(3+)-doped anode and the synergistic interfacial pseudocapacitive behavior satisfy the redox reaction at a high rate,thus increasing rate capability.

关键词： lithium-ion battery(LIB) anode lattice distortion high-entropy oxide(HEO) high-rate performance La^(3+)doping oxygen vacancy(OV)