检索结果-南通市图书馆

Molecular investigation into the transformation of recalcitrant dissolved organic sulfur in refinery sour water during stripping process

引用

Petroleum Science 2024年第3期21卷 2112-2119页

作者： Yu-Guo Li chen he Chun-Mao chen Fan Liu Quan Shi State Key Laboratory of heavy Oil Processing China University of Petroleum State Key Laboratory of Coal Mining and Clean Utilization PetroChina Ningxia Petrochemical Company

Refinery sour water primarily originates from the tops of towers in various units and coker condensate,and cannot be discharged directly to a wastewater treatment plant due to high levels of chemical oxygen demand(COD) and organic sulfur contents. Even after the recovery of H2S from the sour water by the stripping process, the effluent still contains a high concentration of dissolved organic sulfur(DOS), which can have a huge bad influence. While chemical composition of dissolved organic matter(DOM) in refinery wastewater has been extensively studied, the investigation of recalcitrant DOS from sour waters remains unclear. In the present study, chemical composition of sour water DOMs(especially DOS) was investigated using fluorescence spectroscopy(excitation-emission matrix, EEM) and mass spectrometry,including gas chromatography-mass spectrometry(GC-MS) and high-resolution Orbitrap MS. The GC-MS and EEM results showed that volatile and low-aromaticity compounds were effectively removed during the stripping process, while compounds with high hydrophilicity and humification degree were found to be more recalcitrant. The Orbitrap MS results showed that weak-polar oxygenated sulfur compounds were easier to be removed than oxygenated compounds. However, the effluent still contained significant amounts of sulfur-containing compounds with multiple sulfur atoms, particularly in the form of highly unsaturated and aromatic compounds. The Orbitrap MS/MS results of CHOS-containing compounds from the effluent indicate that the sulfur atoms may exist as sulfonates, disulfide bonds, thioethers. Understanding the composition and structure of sour water DOS is crucial for the development of effective treatment processes that can target polysulfide compounds and minimize their impact on the environment.

关键词： Molecular transformation Dissolved organic sulfur Stripping process Refinery sour water Orbitrap MS

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Potential transformation of organic matter by microbes in cryoconite,Tibetan Plateau

引用

Science China Earth Sciences 2024年第6期67卷 1978-1989页

作者： Bixi GUO Yongqin LIU Kevin Xu ZHONG Quan SHI chen he Qiang ZheNG Ruanhong CAI State Key Laboratory of Tibetan Plateau Earth System Environment and Resources(TPESER)Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101China Center for the Pan-Third Pole Environment Lanzhou UniversityLanzhou 730000China Department of Earth Oceanand Atmospheric SciencesUniversity of British ColumbiaVancouverBC V6T 1Z4Canada State Key Laboratory of heavy Oil Processing Petroleum Molecules Engineering Center(PMEC)China University of PetroleumBeijing 102249China State Key Laboratory for Marine Environmental Science Collage of Ocean and Earth SciencesXiamen UniversityXiamen 361102China Fujian Key Laboratory of Marine Carbon Sequestration Xiamen UniversityXiamen 361005China

Microorganisms play an essential role in the glacier carbon cycle;how they transform organic matter in mountain glacial cryoconite remains to be studied.here,we applied ultra-high resolution Fourier transform ion cyclotron resonance mass spectrometry(FT-ICR MS)and deep sequencing of 16S rRNA gene,to investigate the temporal microbial transformation of dissolved organic matter(DOM)of the Tibetan Plateau cryoconite.During the 60-day incubation,we found that DOM in cryoconite underwent a three-stage transformation,with decreasing bioavailability over time.The microbial community did not change much in the first week while degrading DOM molecules that were associated with higher H/C_(wa)and lower O/C_(wa).During days 15-30,DOM composition remained stable while microbial diversity increased.By day 60,the DOM was microbially converted into a higher state of recalcitrance,with higher values of aromatic index,O/C_(wa),and lower H/C_(wa),which contained molecules containing more heteroatoms.Cooperation among various microbial taxa,like Cyanobacteria,Bacteroidota,Gammaproteobacteria,Firmicutes,and Actinobacteriota,drove the DOM transformation in cryoconite.This study sheds light on the in-situ transformation of DOM composition meditated by microbial populations in cryoconite at a temporal scale,providing new insights into understanding the microbial roles in the glacier organic carbon transformation.

关键词： Cryoconite Dissolved organic matter Biodegradation Microbial community Temporal variation

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

The Role of Adipose Tissue-derived Exosomes in Chronic Metabolic Disorders

引用

Current Medical Science 2024年第3期44卷 463-474页

作者： Rui he Yong chen Division of Endocrinology Department of Internal MedicineTongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan430030China Laboratory of Endocrinology & Metabolism Key Laboratory of Vascular Aging of the Ministry of EducationTongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan430030China Branch of National Clinical Research Center for Metabolic Diseases Wuhan430030China

Excessive fat deposition in obese subjects promotes the occurrence of metabolic diseases,such as type 2 diabetes mellitus(T2DM),cardiovascular diseases,and non-alcoholic fatty liver disease(NAFLD).Adipose tissue is not only the main form of energy storage but also an endocrine organ that not only secretes adipocytokines but also releases many extracellular vesicles(EVs)that play a role in the regulation of whole-body metabolism.Exosomes are a subtype of EVs,and accumulating evidence indicates that adipose tissue exosomes(AT Exos)mediate crosstalk between adipose tissue and multiple organs by being transferred to targeted cells or tissues through paracrine or endocrine mechanisms.However,the roles of AT Exos in crosstalk with metabolic organs remain to be fully elucidated.In this review,we summarize the latest research progress on the role of AT Exos in the regulation of metabolic disorders.Moreover,we discuss the potential role of AT Exos as biomarkers in metabolic diseases and their clinical application.

关键词： exosome adipose tissue obesity diabetes chronic metabolic disorder miRNA

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Molecular evolution of Toll-like receptors in rodents

引用

Integrative Zoology 2024年第3期19卷 371-386页

作者： Qianqian SU Yi chen Hongxuan he College of Forestry Central South University of Forestry and TechnologyChangshaChina National Research Center for Wildlife-Borne Diseases Institute of ZoologyChinese Academy of SciencesBeijingChina

Toll-like receptors(TLRs),the key sensor molecules in vertebrates,trigger the innate immunity and prime the adaptive immune system.The TLR family of rodents,the largest order of mammals,typically contains 13 TLR genes.However,a clear picture of the evolution of the rodent TLR family has not yet emerged and the TLR evolutionary patterns are unclear in rodent clades.here,we analyzed the natural variation and the evolutionary processes acting on the TLR family in rodents at both the interspecific and population levels.Our results showed that rodent TLRs were dominated by purifying selection,but a series of positively selected sites(PSSs)primarily located in the ligand-binding domain was also identified.The numbers of PSSs differed among TLRs,and nonviralsensing TLRs had more PSSs than those in viral-sensing TLRs.Gene-conversion events were found between TLR1 and TLR6 in most rodent species.Population genetic analyses showed that TLR2,TLR8,and TLR12 were under positive selection in Rattus norvegicus and R.tanezumi,whereas positive selection also acted on TLR5 and TLR9 in the former species,as well as TLR1 and TLR7 in the latter species.Moreover,we found that the proportion of polymorphisms with potentially functional change was much lower in viral-sensing TLRs than in nonviral-sensing TLRs in both of these rat species.Our findings revealed the first thorough insight into the evolution of the rodent TLR genetic variability and provided important novel insights into the evolutionary history of TLRs over long and short timescales.

关键词： adaptive evolution gene conversion positive selection rodents Toll-like receptors

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Fully Nonlinear Equations of Krylov Type on Riemannian Manifolds with Totally Geodesic Boundary

引用

Acta Mathematica Sinica,English Series 2024年第5期40卷 1293-1307页

作者： Li chen Yan he Faculty of Mathematics and Statistics Hubei Key Laboratory of Applied MathematicsHubei UniversityWuhan 430000P.R.China

In this paper,we study fully nonlinear equations of Krylov type in conformal geometry on compact smooth Riemannian manifolds with totally geodesic boundary.We prove the a priori estimates for solutions to these equati... 详细信息

关键词： The modified Schouten tensor k-convex hessian type equation

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Characterization of Fe-containing particles in chengdu,southwest China,using single-particle aerosol mass spectrometry

引用

Journal of Environmental Sciences 2024年第2期136卷 110-120页

作者： Renjiang he Junke Zhang Luyao chen Wei Zhang Yingwei Xi School of Public health Southwest Medical UniversityLuzhou 646000China Faculty of Geosciences and Environmental Engineering Southwest Jiaotong UniversityChengdu 611756China Sichuan Environmental Monitoring Center Chengdu 610074China

Single-particle aerosol mass spectrometry was used to study the characteristics of Fecontaining particles during winter in chengdu,southwest China.The mass concentrations of PM_(2.5)and PM_(10)during the study period were 64±38 and 89±49μg/m~3,respectively,and NO_(2)and particulate matter were high compared with most other regions of China.The Fecontaining particles were divided into seven categories with different mass spectra,sources and aging characteristics.The highest contribution was from Fe mixed with carbonaceous components(Fe-C,23.1%)particles.Fe was more mixed with sulfate than nitrate and therefore the contribution of Fe mixed with sulfate(Fe-S,20.7%)particles was higher than that of Fe mixed with nitrate(Fe-N,12.5%)particles.The contributions from Fe-containing particles related to primary combustion were high in the small particle size range,whereas aged Fecontaining particles and dust-related particles were mostly found in the coarse particle size range.The air masses mainly originated from the west and east of chengdu,and the corresponding PM_(2.5)concentrations were 79±36 and 55±36μg/m~3,respectively.The west and east air masses showed stronger contributions of Fe-containing particles related to biomass burning(Fe-B)and fossil fuel combustion(Fe-C and Fe-S)particles,respectively.The southwest area contributed the most Fe-containing particles.Future assessments of the effects of Fe-containing particles during heavy pollution period should pay more attention to Fe-C and Fe-S particles.Emission-reduction of Fe-containing particles should consider both local emissions and short-distance transmission from the surrounding areas.

关键词： Fe-containing particles Particle composition Potential source areas Evolution chengdu

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Toxicity mechanisms of photodegraded polyvinyl chloride nanoplastics on pea seedlings

引用

Frontiers of Environmental Science & Engineering 2024年第4期18卷 111-124页

作者： Hao Wu Beibei he Bocheng chen An Liu College of Chemistry and Environmental Engineering Shenzhen UniversityShenzhen 518060China

Nanoplasctics(NPs),which are very small in particle size,exert toxic effect to organisms.Additionally,compared to original NPs,photodegraded NPs would pose higher toxicity.This is because their relatively higher specific surface areas and the presence of additives which can more easily leach.How original NPs and aged NPs affect plant growth has not been widely investigated.This work chose polyvinyl chloride NPs(PVC-NPs)that were subjected to up to 1000 h UV light radiation to explore the impact of PVC-NPs on the growth of pea seedlings(Pisum Sativum L.).The results indicated the existence of PVC-NPs with longer UV light radiation time and higher concentrations had more negative influences on pea seedlings’growth such as germination rate(decreased by 10.6%–22.5%),stem length(decreased by 2.8%–8.1%),dry weight(decreased by 6.3%–7.1%)and fresh weight(decreased by 6.7%–14.8%).It was also noted that photodegraded PVC-NPs resulted in damage to leaf stomata and roots,hindering photosynthesis and absorption of nutrients and hence the decrease in chlorophyll and soluble sugar contents.According to transcriptomic investigation results,the presence of aged PVC-NPs primarily influenced protein processing in endoplasmic reticulum(upregulated metabolic pathway)and phenylpropanoid biosynthesis(downregulated metabolic pathway)of pea seedlings.These results provide an in-depth understanding of how NPs influence the growth of plants.

关键词： Nanoplasctics Polyvinyl chloride Toxicity mechanisms Plant growth

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Toward Trustworthy Decision-Making for Autonomous Vehicles:A Robust Reinforcement Learning Approach with Safety Guarantees

引用

Engineering 2024年第2期33卷 77-89页

作者： Xiangkun he Wenhui Huang chen Lv School of Mechanical and Aerospace Engineering Nanyang Technological UniversitySingapore 639798Singapore

While autonomous vehicles are vital components of intelligent transportation systems,ensuring the trustworthiness of decision-making remains a substantial challenge in realizing autonomous driving.Therefore,we present a novel robust reinforcement learning approach with safety guarantees to attain trustworthy decision-making for autonomous vehicles.The proposed technique ensures decision trustworthiness in terms of policy robustness and collision safety.Specifically,an adversary model is learned online to simulate the worst-case uncertainty by approximating the optimal adversarial perturbations on the observed states and environmental dynamics.In addition,an adversarial robust actor-critic algorithm is developed to enable the agent to learn robust policies against perturbations in observations and dynamics.Moreover,we devise a safety mask to guarantee the collision safety of the autonomous driving agent during both the training and testing processes using an interpretable knowledge model known as the Responsibility-Sensitive Safety Model.Finally,the proposed approach is evaluated through both simulations and experiments.These results indicate that the autonomous driving agent can make trustworthy decisions and drastically reduce the number of collisions through robust safety policies.

关键词： Autonomous vehicle Decision-making Reinforcement learning Adversarial attack Safety guarantee

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Study on damage mechanism and damage distribution of the rear plate under impact of debris cloud

引用

Defence Technology（防务技术） 2024年第5期35卷 151-167页

作者： chenyang Wu Xiaowei chen Qiguang he State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyHaidian DistrictBeijing 100081China School of Mechatronical Engineering Beijing Institute of TechnologyHaidian DistrictBeijing 100081China Institute of Fluid Physics China Academy of Engineering PhysicsMianyang 621900SichuanChina

The debris cloud generated by the hypervelocity impact(HVI)of orbiting space debris directly threatens the spacecraft.A full understanding of the damage mechanism of rear plate is useful for the optimal design of protective structures.In this study,the hypervelocity yaw impact of a cylindrical aluminum projectile on a double-layer aluminum plate is simulated by the FE-SPH adaptive method,and the damage process of the rear plate under the impact of the debris cloud is analyzed based on the debris cloud structure.The damage process can be divided into the main impact stage of the debris cloud and the structural response of the rear plate.The main impact stage lasts a short time and is the basis of the rear plate damage.In the stage of structure response,the continuous deformation and inertial motion of the rear plate dominate the perforation of the rear plate.We further analyze the damage mechanism and damage distribution characteristics of the rear plate in detail.Moreover,the connection between velocity space and position space of the debris cloud is established,which promotes the general analysis of the damage law of debris cloud.Based on the relationship,the features of typical damage areas are identified by the localized fine analysis.Both the cumulative effect and structural response cause the perforation of rear plate;in the non-perforated area,cratering by the impact of hazardous fragments is the main damage mode of the rear plate.

关键词： Damage of rear plate Debris cloud Secondary impact Hypervelocity yaw impact FE-SPH adaptive method

来源：

维普期刊数据库博看期刊

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Volume of fluid simulation of single argon bubble dynamics in liquid steel under RH vacuum conditions

引用

Journal of Iron and Steel Research(International) 2024年第4期31卷 828-837页

作者： Gu-jun chen Sheng-ping he College of Materials Science and Engineering Yangtze Normal UniversityChongqing 400044China College of Materials Science and Engineering Chongqing UniversityChongqing 400044China

Single argon bubble dynamics in liquid steel under Ruhrstahl-heraeus(RH)vacuum conditions were simulated using the volume of fluid method,and the ideal gas law was used to consider bubble growth due to heat transfer and pressure drop.Additional simulation with a constant bubble density was also performed to validate the numerical method,and the predicted terminal bubble shape and velocity were found to agree with those presented in the Grace diagram and calculated by drag correlation,respectively.The simulation results under RH conditions indicate that the terminal bubble shape and velocity cannot be reached.The primary bubble growth occurs within a rising distance of 0.3 m owing to heating by the high-temperature liquid steel;subsequently,the bubble continues to grow under equilibrium with the hydrostatic pressure.When the initial diameter is 8-32 mm,the bubble diameter and rising velocity near the liquid surface are 80-200 mm and 0.5-0.8 m/s,respectively.The bubble rises rectilinearly with an axisymmetric shape,and the shape evolution history includes an initial sphere,(dimpled)ellipsoid,and spherical cap with satellite bubbles.

关键词： Bubble dynamics Liquid steel Volume of fluid Bubble growth Bubble shape Rising velocity

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：