检索结果-南通市图书馆

Particle Distribution Informed by Chain Rigidity in Diblock Copolymer Melts: The Effect of Entropy

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Polymer Science 2024年第3期42卷 388-399,I0009页

作者： Yuguo Chen Shuanhu Qi ying jiang School of Chemistry Beihang UniversityBeijing 100191China

We study the effect of chain rigidity on tailoring the nanoparticle locations for neutral and selective particles embedded in the lamellar morphology formed by semiflexible diblock copolymer chains using self-consistent field calculations. The nanoparticles are modeled through a cavity function, and the semiflexible chains are represented by the continuous Kratsky-Porod chain model. In general situation, the nanoparticles prefer to stay at the interface in order to reduce the interface areas and thus the system free energy. However, the particle distribution at the domain center is subtle, and the underlying physics is intrinsically different depending on the polymer flexibility. In the case of flexible chains, the entropy just contributes a constant shift to the free energy when the nanoparticles move around the domain center indicating that the local metastable state if appears at the domain center is wholly attributed to the local minimum in the enthalpy. If the polymers are rigid, the variation of the particle distribution at the domain center has a close relation with the polymer rigidity and nanoparticle size. In the case of strongly rigid polymers with small nanoparticles, a nearly uniform particle distribution at the domain center is observed, while in other cases, a local enhancement of particle distribution there is found. In contrast to the case of flexible chains, further analysis reveals the crucial role of entropy in controlling the shape of particle distributions at the phase domain. Specifically, the local metastable state appears in the domain center is determined by the large entropy there which arises from the weak coupling of bond orientations that allows the polymer chains to be relatively relaxed. When the particle becomes selective, its distribution in the phase domain exhibits a shift almost uniformly rather than changes its profile, and the underlying physics still holds. In all, our study establishes a strong coupling between the chain rigidity and effect of entropy.

关键词： Semiflexible diblock copolymer Nanoparticle distribution Self-consistent field theory Entropic effect

Ultrafast optical investigation of carrier and spin dynamics in low-dimensional perovskites

在线全文

学校读者我要写书评

暂无评论

Science China(Technological Sciences) 2024年第1期67卷 2-18页

作者： FU JinYue jiang ying FANG HongHua Key Laboratory for Micro-Nano Physics and Technology of Hunan Province School of Physics and ElectronicsHunan UniversityChangsha 410012China State Key Laboratory of Precision Measurement Technology and Instruments Department of Precision InstrumentTsinghua UniversityBeijing 100084China

Low-dimensional perovskite(PVK)materials have attracted significant research interest,because of their quantum-confined effect,tunable band gap structures,and higher stability than that of three-dimensional(3D)PVKs.In semiconductor optoelectronic devices,high speed and small size are closely interlinked.The development of high-speed devices requires researchers to fully understand the properties of materials,especially the dynamic processes such as carrier recombination,separation,and transport,which often play a crucial role in the performance of devices.As an indispensable part of dynamic research,spin relaxation is also of great significance in studying the properties of materials and explore possible applications.Lead halide PVK materials have strong spin-orbit coupling(SOC),which provides a basis for information storage and processing by using spin degrees of freedom.Therefore,studying the carrier and spin dynamics of low-dimensional PVKs is an effective way to understand the internal properties of low-dimensional PVKs clearly.This paper summarizes the latest research progress on the ultrafast carrier and spin dynamics in low-dimensional PVKs,to comprehensively understand their carrier and spin behaviors and present an outlook for relevant studies in this area.

关键词： low-dimensional perovskites carrier dynamics spin dynamics optoelectronic devices

Harnessing innate immune pathways for therapeutic advancement in cancer

在线全文

学校读者我要写书评

暂无评论

Signal Transduction and Targeted Therapy 2024年第4期9卷 1506-1564页

作者： Ankang Hu Li Sun Hao Lin Yuheng liao Hui Yang ying Mao Department of Neurosurgery Huashan HospitalFudan UniversityShanghaiP.R.China Institute for Translational Brain Research Shanghai Medical CollegeFudan University ShanghaiPR.China National Center for Neurological Disorders Huashan HospitalShanghai Medical CollegeFudan UniversityShanghaiP.R.China Shanghai Key Laboratory of Brain Function Restoration and Neural Regeneration Shanghai Clinical Medical Center of NeurosurgeryNeurosurgical Institute of Fudan UniversityHuashan HospitalShanghai Medical CollegeFudan UniversityShanghaiP.R.China State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science and MOE Frontiers Center for Brain Science Institutes of Brain ScienceShanghai Medical CollegeFudan UniversityShanghaiP.R.China Shanghai Key Laboratory of Medical Epigenetics International Co-laboratory of Medical Epigenetics and Metabolism(Ministry of Science and Technology)and Key Laboratory of Metabolism and Molecular Medicine(Ministry of Education)and Molecular and Cell Biology LabInstitutes of Biomedical SciencesShanghai Medical College of Fudan UniversityShanghaiP.R.China

The innate immune pathway is receiving increasing attention in cancer therapy.This pathway is ubiquitous across various cell types,not only in innate immune cells but also in adaptive immune cells,tumor cells,and stromal cells.Agonists targeting the innate immune pathway have shown profound changes in the tumor microenvironment(TME)and improved tumor prognosis in preclinical studies.However,to date,the clinical success of drugs targeting the innate immune pathway remains limited.Interestingly,recent studies have shown that activation of the innate immune pathway can paradoxically promote tumor progression.The uncertainty surrounding the therapeutic effectiveness of targeted drugs for the innate immune pathway is a critical issue that needs immediate investigation.In this review,we observe that the role of the innate immune pathway demonstrates heterogeneity,linked to the tumor development stage,pathway status,and specific cell types.We propose that within the TME,the innate immune pathway exhibits multidimensional diversity.This diversity is fundamentally rooted in cellular heterogeneity and is manifested as a variety of signaling networks.The pro-tumor effect of innate immune pathway activation essentially reflects the suppression of classical pathways and the activation of potential pro-tumor alternative pathways.Refining our understanding of the tumor's innate immune pathway network and employing appropriate targeting strategies can enhance our ability to harness the anti-tumor potential of the innate immune pathway and ultimately bridge the gap from preclinical to clinicalapplication.

关键词： drugs therapeutic innate

Emerging role of regulated cell death in intestinal failure-associated liver disease

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

Hepatobiliary & Pancreatic Diseases International 2024年第3期23卷 228-233页

作者： Si-Yang Cheng Lu jiang ying Wang Wei Cai Department of Pediatric Surgery Xinhua HospitalSchool of MedicineShanghai Jiao Tong UniversityShanghai 200092China Shanghai Key Laboratory of Pediatric Gastroenterology and Nutrition Shanghai 200092China Shanghai Institute for Pediatric Research Shanghai 200092China Division of Pediatric Gastroenterology and Nutrition Xinhua HospitalSchool of MedicineShanghai Jiao Tong UniversityShanghai 200092China

Intestinal failure-associated liver disease(IFALD)is a common complication of long-term parenteral nutrition that is associated with significant morbidity and mortality.It is mainly characterized by cholestasis in children and steatohepatitis in adults.Unfortunately,there is no effective approach to prevent or reverse the disease.Regulated cell death(RCD)represents a fundamental biological paradigm that determines the outcome of a variety of liver diseases.Nowadays cell death is reclassified into several types,based on the mechanisms and morphological phenotypes.Emerging evidence has linked different modes of RCD,such as apoptosis,necroptosis,ferroptosis,and pyroptosis to the pathogenesis of liver diseases.Recent studies have shown that different modes of RCD are present in animal models and patients with IFALD.Understanding the pathogenic roles of cell death may help uncover the underlying mechanisms and develop novel therapeutic strategies in IFALD.In this review,we discuss the current knowledge on how RCD may link to the pathogenesis of IFALD.We highlight examples of cell death-targeted interventions aiming to attenuate the disease,and provide perspectives for future basic and translational research in the field.

关键词： Parenteral nutrition Apoptosis Necroptosis Cholestasis Steatosis

Ferrihydrite transformation impacted by coprecipitation of lignin:Inhibition or facilitation?

在线全文

学校读者我要写书评

暂无评论

Journal of Environmental Sciences 2024年第5期139卷 23-33页

作者： Lin Liu Zhihui Yang Weichun Yang Wen jiang Qi liao Mengying Si Feiping Zhao School of Metallurgy and Environment Central South UniversityChangsha 410083China Chinese National Engineering Research Center for Control&Treatment of Heavy Metal Pollution(CNERC-CTHMP) Changsha 410083China

Lignin is a common soil organic matter that is present in soils,but its effect on the transformation of ferrihydrite(Fh)remains unclear.Organic matter is generally assumed to inhibit Fh transformation.However,lignin can reduce Fh to Fe(Ⅱ),in which Fe(Ⅱ)-catalyzed Fh transformation occurs.Herein,the effects of lignin on Fh transformation were investigated at 75℃ as a function of the lignin/Fh mass ratio(0-0.2),pH(4-8)and aging time(0-96 hr).The results of Fh-lignin samples(mass ratios=0.1)aged at different pH values showed that for Fh-lignin the time of Fh transformation into secondary crystalline minerals was significantly shortened at pH 6 when compared with pure Fh,and the Fe(Ⅱ)-accelerated transformation of Fh was strongly dependent on pH.Under pH 6,at low lignin/Fh mass ratios(0.05-0.1),the time of secondary mineral formation decreased with increasing lignin content.For high lignosulfonate-content material(lignin:Fh=0.2),Fh did not transform into secondary minerals,indicating that lignin content plays a major role in Fh transformation.In addition,lignin affected the pathway of Fh transformation by inhibiting goethite formation and facilitating hematite formation.The effect of coprecipitation of lignin on Fh transformation should be useful in understanding the complex iron and carbon cycles in a soil environment.

关键词： Ferrihydrite transformation Lignin Hematite Goethite Fe(Ⅱ)-catalyzed Reactive Fe(Ⅲ)species

Regulation of rhizosphere microenvironment by rice husk ash for reducing the accumulation of cadmium and arsenic in rice

在线全文

学校读者我要写书评

暂无评论

Journal of Environmental Sciences 2024年第2期136卷 1-10页

作者： Yi jiang Ya Liu Xuantao Yi Peng Zeng Bohan liao Hang Zhou Jiaofeng Gu College of Environmental Science and Engineering Central South University of Forestry and TechnologyChangsha 410004China Hunan Engineering Laboratory for Control of Rice Quality and Safety Changsha 410004China

It is important to reduce Cd and As content in brown rice in contaminated paddy soils.We conducted research on the effects of rice husk ash (RHA) on the Cd and As in the rhizosphere microenvironment (soil,porewater,and iron plaque) and measured the Cd,As,and Si content in rice plants.The main elements in RHA were Si (29.64%) and O (69.17%),which had the maximum adsorption capacity for Cd was 42.49 mg/kg and for As was 18.62 mg/kg.Soil pH and available Si content increased,while soil available Cd and As decreased following application of 0.5%–2%RHA.RHA promote the transformation of Cd to insoluble fraction,while As was transformed from a poorly soluble form to a more active one.RHA reduced Cd content and increased Si content in porewater,and reduced As only at the later rice growth stages.RHA increased the amount of iron plaque,thereby decreasing the Cd content in iron plaque,while increased the As content in it.Cd and inorganic As content in brown rice were decreased,to 0.31 mg/kg and 0.18 mg/kg,respectively.The decrease of Cd in brown rice was due to the decrease of Cd mobility in soil,thereby reducing root accumulation,while the decrease of As in brown rice was affected by the transport from roots to stems.Therefore,RHA can be considered as a safe and efficient in-situ remediation amendment for Cd and As co-contaminated paddy soil.

关键词： Rice husk ash(rha) Cadmium Arsenic Silicon Rice Soil

HTDcr:a job execution framework for high-throughput computing on supercomputers

在线全文

学校读者我要写书评

暂无评论

Science China(Information Sciences) 2024年第1期67卷 69-85页

作者： Jiazhi jiang Dan HUANG Hu CHEN Yutong LU Xiangke liao School of Computer Science and Engineering Sun Yat-sen University School of Software Engineering South China University of Technology

High-throughput computing(HTC) is a computing paradigm that aims to accomplish jobs by easily breaking them into smaller,independent components.However,it requires a large amount of computing power for a long time.Most existing HTC frameworks are job-oriented without support for coscheduling with hardware architecture and task-level execution.Also,most of the frameworks reach a limited scale,and their usability needs further improvement.Herein,we present HTDcr,a job execution framework for the HTC on supercomputers.This study aims to improve the throughput,task dispatching,and usability of the framework.In detail,the throughput optimizations include a sophisticated designed task management system,a hierarchical scheduler,and the co-optimization of the task-scheduling strategy with the application and hardware characteristics.The optimizations for usability include a programable execution workflow,mechanisms for more robust and reliable service qualities,and a fine-grained resource allocation system for the colocation of multiple jobs.According to our evaluations,HTDcr can achieve outstanding scalability and high throughput on large-scale clusters for the HTC workload.We evaluate HTDcr with several microbenchmarks and real-world applications on Tianhe-2 and Sunway TaihuLight to demonstrate its effects on existing design mechanisms.For instance,the task scheduling for two real-world applications integrated with the application and hardware characteristics achieves 1.7× and 1.9× speedups over the basic task-scheduling strategy.

关键词： high-throughput computing supercomputer task scheduling middleware password guessing

Experimental Study on the Molten Salt at Micron Scale during the Melting Process

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Journal of Thermal Science 2024年第1期33卷 70-85页

作者： TIAN Ziqian liao Zhirong XU Chao FANG Yongzhe jiang Kaijun YUAN Mengdi Key Laboratory of Power Station Energy Transfer Conversion and System Ministry of Education of ChinaSchool of Energy Power and Mechanical EngineeringNorth China Electric Power UniversityBeijing 102206China

The investigation of the melting behaviors of the molten salt at micron scale during the melting process is critical for explaining the solid-liquid phase transition mechanism.In this paper,a novel experimental system and analysis method were proposed to study the melting process with three heating rates in the range of1-10℃/min of the solar salt at micron scale.The solid-liquid boundary morphology and phase transition kinetics of molten salt particles were focused on.Meanwhile,the correlations between liquid fraction,temperature and time under different heating rates were studied.The solid-liquid boundary morphology was depicted by the visualized experimental set-up,and the instantaneous liquid volume fraction during the non-isothermal phase transition was obtained.Then,the correlation between temperature and liquid volume fraction was proposed to reveal the evolution of the solid-liquid boundary with temperature at different heating rates.Furthermore,the non-isothermal phase transition kinetic equation was established by introducing a constant parameter(V_(a,b)),and more kinetic parameters such as 1g V_(a,b) and-lg V_(a,b)/b were studied.The results showed that the exponent b is not sensitive to the heating rate with a range of 3-5 for solar salt particles.However,the heating rate influences the value of V_(a,b) and presents a positive relationship.Besides,the non-isothermal phase transition kinetic equations at different heating rates in the range of 1-10℃/min can be quickly predicted by the proposed improved experimental test method.This study could fill the research insufficiency and provide significant guidance for future research on the solid-liquid transition mechanism of molten salts at micron scale.

关键词： molten salt non-isothermal phase transition solid-liquid boundary morphology liquid volume fraction micron scale melting process

Highly Aligned Graphene Aerogels for Multifunctional Composites

在线全文

学校读者我要写书评

暂无评论

Nano-Micro Letters 2024年第6期16卷 276-342页

作者： ying Wu Chao An Yaru Guo Yangyang Zong Naisheng jiang Qingbin Zheng Zhong‑Zhen Yu Beijing Advanced Innovation Center for Materials Genome Engineering School of Materials Science and EngineeringUniversity of Science and Technology BeijingBeijing 100083People’s Republic of China Institute of Materials Intelligent Technology Liaoning Academy of MaterialsShenyang 110004People’s Republic of China School of Science and Engineering The Chinese University of Hong KongShenzhenShenzhenGuangdong 518172People’s Republic of China State Key Laboratory of Organic‑Inorganic Composites College of Materials Science and EngineeringBeijing University of Chemical TechnologyBeijing 100029People’s Republic of China

Stemming from the unique in-plane honeycomb lattice structure and the sp^(2)hybridized carbon atoms bonded by exceptionally strong carbon–carbon bonds,graphene exhibits remarkable anisotropic electrical,mechanical,and thermal properties.To maximize the utilization of graphene’s in-plane properties,pre-constructed and aligned structures,such as oriented aerogels,films,and fibers,have been designed.The unique combination of aligned structure,high surface area,excellent electrical conductivity,mechanical stability,thermal conductivity,and porous nature of highly aligned graphene aerogels allows for tailored and enhanced performance in specific directions,enabling advancements in diverse fields.This review provides a comprehensive overview of recent advances in highly aligned graphene aerogels and their composites.It highlights the fabrication methods of aligned graphene aerogels and the optimization of alignment which can be estimated both qualitatively and quantitatively.The oriented scaffolds endow graphene aerogels and their composites with anisotropic properties,showing enhanced electrical,mechanical,and thermal properties along the alignment at the sacrifice of the perpendicular direction.This review showcases remarkable properties and applications of aligned graphene aerogels and their composites,such as their suitability for electronics,environmental applications,thermal management,and energy storage.Challenges and potential opportunities are proposed to offer new insights into prospects of this material.

关键词： Highly aligned graphene aerogels Quantitative characterization of alignment Multifunctional composites Anisotropic properties Multifunctional applications