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Comparative study on the hydrogen storage performance of as-milled MgRENi rapid quenched alloy catalyzed by metal sulfides

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Journal of Magnesium and Alloys 2024年第5期12卷 2010-2023页

作者： Xiaoping Dong Zhaoqing zhang liying Yang Shenghai xin Dandan Su Zhiyuan li Department of Mechanical Design and Manufacture and Automation Hebei UniversityBaoding 071000PR China Baoding New Energy Vehicle Power Engineering Technology Research Center Hebei UniversityBaoding 071002PR China Hebei Technology Innovation Center for lightweight of New Energy Vehicle Power System(Preparation) Hebei UniversityBaoding 071002PR China

The composites of Mg_(20)Pr_(1)Sm_(3)Y_(1)Ni_(10)as-quenched alloy and 3 wt.%M(M=CoS,CoS_(2),MoS_(2))catalyst were prepared by high-speed vibration ball *** effects of metal sulfides on the hydrogenation and dehydrogenation dynamics of alloys were *** results show that the as-milled composites contain a large number of amorphous embedded by a small amount of nanocrystals,and there are many point *** ball milling,the crystal grain size in the composites containing CoS is relatively larger,followed by CoS_(2)and MoS_(2)*** hydrogenation,the amorphous phase is crystallized to form Mg_(2)NiH_(4),YH_(3),Pr_(8)H_(18.96),Sm_(3)H_7,Mg,Co or Mo phases,however,Mg_(2)Ni,YH_(2),PrH_(2)and Ni_(3)Y phases appeared after *** maximum hydrogenation capacity of the composites containing CoS,CoS_(2)and MoS_(2)are 3.939,4.265 and 4.507 wt.%,*** hydrogenation saturation ratio of composite containing MoS_(2)is higher than that of the composites containing CoS and CoS_(2).The dehydrogenation activation energy of the composites containing CoS,CoS_(2)and MoS_(2)is 107.76,68.43 and 63.28 ***^(-1).H_(2).On the improvement of hydrogen storage performance of Mg_(20)Pr_(1)Sm_(3)Y_(1)Ni_(10)alloy,the catalytic effect of MoS_(2)sulfide is better than that of CoS_(2)sulfide,and which is better than CoS sulfide.

关键词： Mg_(20)Pr_(1)Sm_(3)Y_(1)Ni_(10)as-quenched alloy CoS CoS_(2)and MoS_(2)sulfide Milling Activation energy Hydrogen storage dynamics

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Geomorphology-oriented theoretical framework and construction method for value-added DEM

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Journal of Geographical Sciences 2024年第1期34卷 165-184页

作者： zhang Haiping TANG Guoan XIONG liyang YANG xin li Fayuan Key Laboratory of Virtual Geographic Environment Ministry of EducationNanjing Normal UniversityNanjing 210023China School of Geography Nanjing Normal UniversityNanjing 210023China Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application Nanjing 210023China

Digital elevation model(DEM)plays a fundamental role in the study of the earth system by expressing surface configuration,understanding surface process,and revealing surface *** is widely used in analysis and modeling in the field of ***,traditional DEM has the defect of single attribute,which is difficult to support the research in earth system science oriented to geoscience process and mechanism ***,realizing the value-added data model on the basis of traditional DEM is necessary to serve digital elevation modeling and terrain analysis under the background of a new geomorphology research paradigm and earth observation technology.A theoretical framework for value-added DEM that mainly includes concept,connotation,content,and categories,is constructed in this *** relationship between different types of value-added DEMs as well as the research significance and application category of this theoretical framework are also *** following are different methods of value-added DEMs:(1)value-added methods of DEM space and time dimensions that emphasize the integration of the ground and underground as well as coupling of time and space,(2)attribute-based value-added methods composed of material(including underground,surface,and ground)and morphological properties,and(3)value-added methods of features and physical elements that consider geographical objects and landform features formed by natural processes and artificial *** digital terrace,slope,and watershed models are used as examples to illustrate application scenarios of the three kinds of value-added *** study aims to improve expression methods of DEMs under the background of new surveying and mapping technologies by adding value to the DEM at three levels of dimensions,attributes,and elements as well as support knowledge-driven digital geomorphological analysis in the era of big data.

关键词： spatial data model value-added DEM digital terrain analysis geomorphological ontology geomorphology

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Surgical techniques to prevent delayed gastric emptying after pancreaticoduodenectomy

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Hepatobiliary & Pancreatic Diseases International 2024年第5期23卷 449-457页

作者： Peng Duan Lu Sun Kai Kou xin-Rui li Ping zhang Department of Hepatobiliary and Pancreatic Surgery General Surgery Centerthe First Hospital of Jilin UniversityChangchun 130021China Department of Dental Implantology Hospital of StomatologyJilin UniversityChangchun 130021China

Background: Delayed gastric emptying(DGE) is one of the most common complications after pancreaticoduodenectomy(PD). DGE represents impaired gastric motility without significant mechanical obstruction and is associated with an increased length of hospital stay, increased healthcare costs, and a high readmission rate. We reviewed published studies on various technical modifications to reduce the incidence of DGE. Data sources: Studies were identified by searching Pub Med for relevant articles published up to December 2022. The following search terms were used: “pancreaticoduodenectomy”, “pancreaticojejunostomy”, “pancreaticogastrostomy”, “gastric emptying”, “gastroparesis” and “postoperative complications”. The search was limited to English publications. Additional articles were identified by a manual search of references from key articles. Results: In recent years, various surgical procedures and techniques have been explored to reduce the incidence of DGE. Pyloric resection, Billroth II reconstruction, Braun's enteroenterostomy, and antecolic reconstruction may be associated with a decreased incidence of DGE, but more high-powered studies are needed in the future. Neither laparoscopic nor robotic surgery has demonstrated superiority in preventing DGE, and the use of staplers is controversial regarding whether they can reduce the incidence of DGE. Conclusions: Despite many innovations in surgical techniques, there is no surgical procedure that is superior to others to reduce DGE. Further larger prospective randomized studies are needed.

关键词： Pancreaticoduodenectomy Delayed gastric emptying Postoperative complications Surgical techniques

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不确定条件下固定上网电价政策的优化和评估

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北京邮电大学学报 2017年第4期40卷 41-47页

作者：李力张昕天津师范大学管理学院天津300387

为准确评价固定上网电价(FIT)政策效果和优化FIT水平,提出了优化投资者决策行为的量化模型,研究了可再生能源产出的不确定性对投资者最优投资时间和装机容量的影响,同时以政策成本最小化的方式,优化政府完成预期装机部署目标时所需的FI... 详细信息

为准确评价固定上网电价(FIT)政策效果和优化FIT水平,提出了优化投资者决策行为的量化模型,研究了可再生能源产出的不确定性对投资者最优投资时间和装机容量的影响,同时以政策成本最小化的方式,优化政府完成预期装机部署目标时所需的FIT水平.实证方面,使用实物期权方法和最小二乘蒙特卡洛模拟,以中国近海离岸风电投资成本等参数,评价和优化了当前的FIT水平.结果表明,目前中国近海离岸风电的补贴水平0.137 USD/k Wh不足以覆盖投资者产量波动带来的风险溢价,政府应将补贴水平提高至0.146 USD/k Wh才可有效刺激投资.

关键词：固定上网电价近海离岸风电投资实物期权不确定性

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On the Performances of Estimating Stellar Atmospheric Parameters from CSST Broad-band Photometry

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Research in Astronomy and Astrophysics 2024年第4期24卷 161-173页

作者： Rui-Feng Shi Yang Huang xin-Yi li Hua-Wei zhang School of Astronomy and Space Science University of Chinese Academy of SciencesBeijing 100049China South-Western Institute for Astronomy Research Yunnan UniversityKunming 650500China CAS Key Lab of Optical Astronomy Key Laboratory of Space Astronomy and TechnologyNational Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China College of Physics and Electronic Engineering Qilu Normal UniversityJinan 250200China Department of Astronomy School of PhysicsPeking UniversityBeijing 100871China Kavli Institute for Astronomy and Astrophysics Peking UniversityBeijing 100871China

Deriving atmospheric parameters of a large sample of stars is of vital importance to understand the formation and evolution of the Milky *** surveys,especially those with near-ultraviolet filters,can offer accurate measurements of stellar parameters,with the precision comparable to that from low/medium resolution *** this study,we explore the capability of measuring stellar atmospheric parameters from Chinese Space Station Telescope(CSST)broad-band photometry(particularly in the near-ultraviolet bands),based on synthetic colors derived from model *** find that colors from the optical and near-ultraviolet filter systems adopted by CSST show significant sensitivities to the stellar atmospheric parameters,especially the *** to our mock data tests,the precision of the photometric metallicity is quite high,with typical values of0.17 and 0.20 dex for dwarf and giant stars,*** precision of the effective temperature estimated from broad-band colors are within 50 K.

关键词： methods:data analysis stars:abundances surveys

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Construction of multifunctional lanthanum manganese mixed nanoparticles mediated by ionic liquids for selective aerobic oxidation of cyclohexane

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Rare Metals 2024年第5期43卷 2205-2221页

作者： Hao li Rui-Rui zhang Ke-xin li Shuang Wei Yu-Mei liu Rui-Xia liu Beijing Key Laboratory of Ionic liquids Clean Process CAS Key Laboratory of Green Process and EngineeringState Key Laboratory of Multiphase Complex SystemsInstitute of Process EngineeringChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China

Selective oxidation of alkanes to produce highvalue chemicals is an essential strategy and means to realize efficient utilization of *** this work,a strategy of lanthanum manganese mixed metal oxides(LMMO)regulated via a facile ionic liquid(IL)-assisted hydrothermal method was proposed to construct the multifunctional catalysts,which exhibited excellent catalytic performance in the selective aerobic oxidation of *** 8.9%cyclohexane conversion with 90%KA oi(cyclohexanol and cyclohexanone)selectivity was achieved over the optimal LMMO catalyst under mild *** effects of anion type,carbon chain length and concentration of ILs on the structure and properties of catalysts were investigated through various characterizations,indicating the structure-directing and template effect of ILs on the multifunctional *** formation of self-assembled spherical nanoparticles followed the"dissolution-nucleation-proliferation"mechanism with the introduction of 1-butyl-3-methylimidazolium hydrogen sulfate,ascribing the synergistic effect between the microenvironment of ILs and the hydrothermal ***,the high reactive oxygen concentration redox capacity,and suitable basic sites of LMMO catalysts mediated by ILs enhance the activation of C-H bonds and molecular oxygen,simultaneously influencing the adsorption and desorption of the substrate.A comprehensive understanding of the high KA oil selectivity and radical reaction mechanism was elucidated based on in situ diffuse reflectance infrared Fourier transform spectroscopy(DRIFTS)and radical trapping *** recycling and regeneration experiments further illuminated that the removal of adsorbed cyclohexanone acting on the LMMO catalyst was the key to achieve high KA oil selectivity.

关键词： Ionic liquids Nanoparticle Multifunctional catalyst Cyclohexane oxidation

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Influence of friction-lubrication characteristics varying with rolling speed on instability of chatter and slip in cold tandem rolling process

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Journal of Iron and Steel Research International 2024年第4期31卷 894-908页

作者： Yan-li xin Zhi-ying Gao Bo Tian Qing-dong zhang School of Mechanical Engineering University of Science and Technology BeijingBeijing 100083China

In the high-speed cold tandem rolling process of thin plate,chatter or slip instability gives rise to the deterioration of equipment and product *** instability behavior is closely related to interfacial friction-lubrication con-dition which is generally characterized by the friction ***,with higher and higher speed requirements,the commonly used model of friction coefficient is no longer applicable and accurate.A novel approach is suggested to calculate the speed-dependent friction coefficient,in which the viscosity-pressure-temperature effects of the lubricant,surface roughness states of work rolls and rolled piece are comprehensively involved and the mixed flm lubrication theory is ***,the influences of friction coefficient on the instability of slip and chatter are investigated for a five-stand cold tandem rolling *** one side,the critical friction coefficient for each stand is determined by calculating the corresponding slip factor;on the other hand,the friction coefficient varying with rolling speed is combined with the model of theoretical critical rolling speed presented under constant friction coefficient,so that the speed threshold is ***,the stable and unstable regions corresponding to the rear three stands are individually discussed,and the technical strategies are proposed to suppress both slip and chatter frequently occurring in the actual rolling process.

关键词： Cold tandem rolling:Oil film thickness Speed-dependent friction coefficient-Slip:Chatter

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Research on ozone formation sensitivity based on observational methods:Development history,methodology,and application and prospects in China

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Journal of Environmental Sciences 2024年第4期138卷 543-560页

作者： Wanghui Chu Hong li Yuanyuan Ji xin zhang likun Xue Jian Gao Cong An State Key Laboratory of Environmental Criteria and Risk Assessment Chinese Research Academy of Environmental SciencesBeijing 100012China Environment Research Institute Shandong UniversityQingdao 266237China

Observation-based method for O_(3)formation sensitivity research is an important tool to analyze the causes of ground-level O_(3)pollution,which has broad application potentials in determining the O_(3)pollution formation mechanism and developing prevention and control *** paper outlined the development history of research on O_(3)formation sensitivity based on observational methods,described the principle and applicability of the methodology,summarized the relative application results in China and provided recommendations on the prevention and control of O_(3)pollution in China based on relevant study results,and finally pointed out the shortcomings and future development prospects in this field in *** overview study showed that the O_(3)formation sensitivity in some urban areas in China in recent years presented a gradual shifting tendency from the VOC-limited regime to the transition regime or the NO_(x)-limited regime due to the implementation of the O_(3)precursors emission reduction policies;O_(3)pollution control strategies and precursor control countermeasures should be formulated based on local conditions and the dynamic control capability of O_(3)pollution control measures should be *** are still some current deficiencies in the study field in ***,it is recommended that a stereoscopic monitoring network for atmospheric photochemical components should be further constructed and improved;the atmospheric chemical mechanisms should be vigorously developed,and standardized methods for determining the O_(3)formation sensitivity should be established in China in the near future.

关键词： Observation-based method Ozone formation sensitivity Ozone pollution prevention and control VOCs NO_(x) OBM

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Pulmonary alveolar proteinosis induced by X-linked agammaglobulinemia:A case report

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World Journal of Clinical Cases 2024年第9期12卷 1644-1648页

作者： Ting zhang Ming li li Tan xin li Department of Respiratory Medicine Kunming Children´s HospitalKunming 650228Yunnan ProvinceChina Department of Emergency Kunming Children's HospitalKunming 650228Yunnan ProvinceChina

BACKGROUND Pulmonary alveolar proteinosis(PAP)and X-linked agammaglobulinemia(XLA)are rare diseases in *** theories infer that immunodeficiency can induce PAP,but these reports are almost all review articles,and there is little clinical *** report the case of a child with both PAP and *** SUMMARY A 4-month-old boy sought medical treatment due to coughing and difficulty in breathing for>2 *** had been hospitalized multiple times due to respiratory infections and *** computed tomography and alveolar lavage fluid showed typical PAP-related *** testing confirmed that the boy also had *** total lung alveolar lavage and intravenous immunoglobulin replacement therapy,the boy recovered and was *** the follow-up period,the number of respiratory infections was significantly reduced,and PAP did not *** XLA can induce PAP and improving immune function contributes to the prognosis of children with this type of PAP.

关键词： Pulmonary alveolar proteinosis X-linked agammaglobulinemia Children Immunodeficiency Alveolar lavage Case report

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Effects of serum proteins on corrosion rates and product bioabsorbability of biodegradable metals

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Regenerative Biomaterials 2024年第1期3卷 132-148页

作者： Hongjie zhang xin li Zehua Qu Wanqian zhang Qunsong Wang Dinglingge Cao Yaoben Wang xin Wang Yang Wang lin Yu Jiandong Ding State Key Laboratory of Molecular Engineering of Polymers Department of Macromolecular ScienceFudan UniversityShanghai 200438China

Corrodible metals are the newest kind of biodegradable materials and raise a new problem of the corrosion ***,the removal of the precipitated products has been unclear and even largely ignored in ***,we find that albumin,an abundant macromolecule in serum,enhances the solubility of corrosion products of iron in blood mimetic Hank’s solution *** is universal for other main biodegradable metals such as magnesium,zinc and polyester-coated *** also influences corrosion rates in diverse trends in Hank’s solution and normal *** on quantitative study theoretically and experimentally,both the effects on corrosion rates and soluble fractions are interpreted by a unified mechanism,and the key factor leading to different corrosion behaviors in corrosion media is the interference of albumin to the Ca/P passivation layer on the metal *** work has illustrated that the interactions between metals and media macromolecules should be taken into consideration in the design of the next-generation metal-based biodegradable medical devices in the formulism of precision *** improved Hank’s solution in the presence of albumin and with a higher content of initial calcium salt is suggested to access biodegradable metals potentially for cardiovascular medical devices,where the content of calcium salt is calculated after consideration of chelating of calcium ions by albumin,resulting in the physiological concentration of free calcium ions.

关键词： biodegradable metal macromolecule albumin corrosion bioabsorbability iron polylactide magnesium zinc

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