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Chinese Chemical Letters 2014年第5期25卷 815-818页

作者： Yong Zhang Mei-Ying Xu tie-kun jiang Wei-Zhe Huang jiang-Yu Wu School of Material Sciences & Engineering Wuhan Institute of Technology

Low generational（G0–G2,G for generation） polyamidoamine（PAMAM） dendrimers were investigated as enhancers to improve the aqueous solubility of folic acid at pH 11 and pH *** these two cases,the solubility of folic acid increases with both the dendrimer concentration and ***,the solubilization mechanism is *** electrostatic interaction between the primary amines of dendrimers and the ionized carboxylic groups of folic acid dominates the dissolution process at pH 11 while the increase of the solubility of folic acid at pH 5 is attributed to the hydrophobic encapsulation inside the dendrimer *** addition,for comparison ethylenediamine was used as a small molecule control to examine the ‘‘dendritic effect＇＇ in the dendrimer-related solubilization ***,PAMAM dendrimers exhibit,at pH 5,a significant superiority over ethylenediamine in enhancing solubility,whereas this ‘‘dendritic effect＇＇ cannot be observed under the basic condition.

关键词： Polyamidoamine Dendrimer Folic acid Electrostatic interaction Hydrophobic encapsulation

Numerical and experimental investigation into the evolution of the shock wave when a muzzle jet impacts a constrained moving body

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Defence Technology（防务技术） 2024年第3期33卷 317-326页

作者： Zijie Li Hao Wang Changshun Chen kun jiang School of Energy and Power Engineering Nanjing University of Science and TechnologyNanjing 210016China

The gun-track launch system is a new special launch device that connects the track outside the *** it is constrained by the track,the characteristics of development of the muzzle jet differ from those of the traditional muzzle ***,it changes from freely developing to doing so in a constrained manner,where this results in an asymmetric direction of flow as well as spatio-temporal coupling-induced interference between various shock waves and the formation of *** this background,the authors of this article formulate and consider the development and characteristics of evolution of the muzzle jet as it impacts a constrained moving *** designed simulations to test the gun-track launch system,and established a numerical model based on the dynamic grid method to explore the development and characteristics of propagation of disturbances when the muzzle jet impacted a constrained moving *** also considered models without a constrained track for the sake of *** results showed that the muzzle jet assumed a circumferential asymmetric shape,and tended to develop in the area above the *** the test platform was close to the ground,the muzzle jet was subjected to reflections from it that enhanced the development and evolution of various forms of shock waves and vortices in the muzzle jet to exacerbate its rate of distortion and asymmetric *** in turn led to significant differences in the changes in pressure at symmetric points that would otherwise have been *** results of a comparative analysis showed that the constrained track could hinder the influence of reflections from the ground on the muzzle jet to some extent,and could reduce the velocity of the shock waves inducing the motion of the muzzle as well as the Mach number of the moving *** work here provides a theoretical basis and the requisite technical support for applications of the gun-track launch *** also sheds light on the

关键词： Shock wave/vortex interference Muzzle jet Constrained boundary Dynamic grid

Disentangling distinct Cu surface sites for electrocatalytic CO_(2)-to-CO and CO-to-C_(2+)conversion

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Science China Chemistry 2024年第4期67卷 1047-1048页

作者： kun jiang Wen-Bin Cai Interdisciplinary Science Research Centre School of Mechanical EngineeringShanghai Jiao Tong UniversityShanghai 200240China Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials Collaborative Innovation Center of Chemistry for Energy MaterialsDepartment of ChemistryFudan UniversityShanghai 200438China

Electrochemical CO_(2)reduction reaction(CO_(2)RR)is a promising strategy to curb anthropogenic carbon emissions,for which intermittent renewable electricity could be stored as chemical energy within carbon-based fuel... 详细信息

关键词： carbon Electrochemical surface

Characteristics of Particulate Matter Emissions for Low-Sulfur Heavy Oil Used in Low-Speed Two-Stroke Diesel Engines of Ocean-Going Ships

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Journal of Thermal Science 2024年第2期33卷 739-750页

作者： WU Gang MA Qianli WEI Lijiang jiang Guohe WANG Tengfei LI tie Merchant Marine College Shanghai Maritime UniversityShanghai201306China State Key Laboratory of Ocean Engineering Shanghai Jiao Tong UniversityShanghai200240China

In this work,particulate matter(PM) emissions from a large two-stroke,low-speed marine diesel engine were investigated when the engine was operated with low-sulfur heavy fuel oil(HFO) at various *** samples were collected in situ from the engine exhaust to determine the detailed physical and chemical *** nanostructure and morphology of the nanoparticles were analyzed using transmission electron microscopy images(TEM).The results show that volatile organic carbon(OC) accounts for more than 80% in the HFO particles and leads to an increase in particle *** thermodynamic conditions of a low-speed engine favor the behavior of capturing the soluble organic components.A large number of spherical char HFO particles with aerodynamic diameters of 0.2 μm-0.5 μm and a suspected inner metal core were *** two peak aerodynamic diameters of the HFO nanoparticles are 15 nm and 86 *** morphological differences among the HFO nanoparticles in varied engine conditions represent the formation process from primary nascent particles to mature graphitized particles caused by *** above study will be valuable for understanding the characteristics of PM emissions from low-sulfur HFO to achieve the ship PM emissions reduction target.

关键词： low-speed diesel engine maritime regulations heavy fuel oil TEM particles size and distribution

Ca_(2)MnO_(4)-layered perovskite modified by NaNO_(3)for chemical-looping oxidative dehydrogenation of ethane to ethylene

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Chinese Journal of Chemical Engineering 2024年第4期68卷 53-64页

作者： Weixiao Ding kun Zhao Shican jiang Zhen Huang Fang He College of Chemistry and Bioengineering Guilin University of TechnologyGuilin 541006China Guangzhou Institute of Energy Conversion Chinese Academy of SciencesGuangzhou 510640China School of Chemistry and Chemical Engineering Nanjing University of Science and TechnologyNanjing 210094China

Chemical-looping oxidative dehydrogenation(CL-ODH)is a process designed for the conversion of alkanes into olefins through cyclic redox reactions,eliminating the need for gaseous O_(2).In this work,we investigated the use of Ca_(2)MnO_(4)-layered perovskites modified with NaNO_(3) dopants,serving as redox catalysts(also known as oxygen carriers),for the CL-ODH of ethane within a temperature range of 700-780℃.Our findings revealed that the incorporation of NaNO_(3) as a modifier significantly-nhanced the selectivity for-thylene generation from Ca_(2)MnO_(4).At 750℃and a gas hourly space velocity of 1300 h^(-1),we achieved an-thane conversion up to 68.17%,accompanied by a corresponding-thylene yield of 57.39%.X-ray photoelectron spectroscopy analysis unveiled that the doping NaNO_(3) onto Ca_(2)MnO_(4) not only played a role in reducing the oxidation state of Mn ions but also increased the lattice oxygen content of the redox ***,formation of NaNO_(3) shell on the surface of Ca_(2)MnO_(4) led to a reduction in the concentration of manganese sites and modulated the oxygen-releasing behavior in a step-wise *** modulation contributed significantly to the enhanced selectivity for ethylene of the NaNO_(3)-doped Ca_(2)MnO_(4) *** findings provide compelling evidence for the potential of Ca_(2)MnO_(4)-layered perovskites as promising redox catalysts in the context of CL-ODH reactions.

关键词： Chemical-looping oxidative dehydrogenation Ethane Ethylene NaNO_(3)-doped Ca_(2)MnO_(4)redox catalyst Layered perovskites

Discovering Latent Variables for the Tasks With Confounders in Multi-Agent Reinforcement Learning

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IEEE/CAA Journal of Automatica Sinica 2024年第7期11卷 1591-1604页

作者： kun jiang Wenzhang Liu Yuanda Wang Lu Dong Changyin Sun the School of Automation Southeast UniversityNanjing 210096China the School of Artificial Intelligence Anhui UniversityHefei 230601China IEEE the School of Cyber Science and Engineering Southeast UniversityNanjing 211189China the Engineering Research Center of Autonomous Unmanned System Technology Ministry of EducationHefei 230601China

Efficient exploration in complex coordination tasks has been considered a challenging problem in multi-agent reinforcement learning(MARL). It is significantly more difficult for those tasks with latent variables that agents cannot directly observe. However, most of the existing latent variable discovery methods lack a clear representation of latent variables and an effective evaluation of the influence of latent variables on the agent. In this paper, we propose a new MARL algorithm based on the soft actor-critic method for complex continuous control tasks with confounders. It is called the multi-agent soft actor-critic with latent variable(MASAC-LV) algorithm, which uses variational inference theory to infer the compact latent variables representation space from a large amount of offline ***, we derive the counterfactual policy whose input has no latent variables and quantify the difference between the actual policy and the counterfactual policy via a distance function. This quantified difference is considered an intrinsic motivation that gives additional rewards based on how much the latent variable affects each agent. The proposed algorithm is evaluated on two collaboration tasks with confounders, and the experimental results demonstrate the effectiveness of MASAC-LV compared to other baseline algorithms.

关键词： Latent variable model maximum entropy multi-agent reinforcement learning(MARL) multi-agent system

Flux phases in the extended Hubbard model on the triangular lattice

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Science China(Physics,Mechanics & Astronomy) 2024年第9期67卷 148-153页

作者： Yuge Chen kun jiang Yi Zhang jiangping Hu Beijing National Laboratory for Condensed Matter Physics and Institute of Physics Chinese Academy of SciencesBeijing 100190China School of Physical Sciences University of Chinese Academy of SciencesBeijing 100190China Department of Physics and Institute for Quantum Science and Technology Shanghai UniversityShanghai 200444China Shanghai Key Laboratory of High Temperature Superconductors and International Center of Quantum and Molecular Structures Shanghai UniversityShanghai 200444China Kavli Institute of Theoretical Sciences University of Chinese Academy of SciencesBeijing 100190China New Cornerstone Science Laboratory Beijing 100190China

Using the unrestricted Hartree-Fock variational method,we study the extended Hubbard model in the triangular lattice at 3/4 *** to the nesting instability of the Fermi surface,various density wave states compatible with the 2×2 supercell are found as the ground state by tuning the onsite and nearest neighbor repulsions U and ***,the flux phases with complex bond order parameters are realized in a wide range of the U-V phase *** also acquire nontrivial topological properties due to the spontaneous breaking of the time-reversal *** study suggests that the flux phases can be stabilized by the interplay between short-range repulsive interactions in correlated electron systems.

关键词： flux state triangular lattice Hubbard model

Fifty-five cases of hepatic alveolar echinococcosis combined with lymph node metastasis:A retrospective study

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World Journal of Gastroenterology 2024年第23期30卷 2981-2990页

作者： Yilizhati Aimaitijiang tie-Min jiang Ying-Mei Shao Tuerganaili Aji State Key Laboratory on Pathogenesis Prevention and Treatment of High Incidence Diseases in Central AsiaThe First Clinical CollegeXinjiang Medical UniversityUrumqi 830011Xinjiang Uygur Autonomous RegionChina The First Ward of Hepatobiliary and Pancreatic Surgery Tumor Hospital Affiliated to Xinjiang Medical UniversityUrumqi 830011Xinjiang Uygur Autonomous RegionChina Department of Hepatobiliary&Hydatid Diseases Digestive&Vascular Surgery CenterThe First Affiliated Hospital of Xinjiang Medical UniversityUrumqi 830054Xinjiang Uygur Autonomous RegionChina Xinjiang Clinical Research Center for Echinococcosis and Hepatobiliary Diseases The First Affiliated Hospital of Xinjiang Medical UniversityUrumqi 830054Xinjiang Uygur Autonomous RegionChina

BACKGROUND Lymph node metastasis is a specific type of metastasis in hepatic alveolar echinococcosis(AE).Currently,there is a scarcity of describing the clinical characteristics and lymph node metastasis rules of patients with hepatic AE combined with lymph node metastasis and its mechanism and management are still *** hepatectomy combined with regional lymph node dissection is a better *** To analyse the clinical features of hepatic AE combined with lymph node metastasis to explore its treatment and *** A total of 623 patients with hepatic AE admitted to the First Affiliated Hospital of Xinjiang Medical University from 1 January 2012 to 1 January 2022 were retrospectively ***-five patients with combined lymph node metastasis were analysed for their clinical data,diagnosis and treatment methods,follow-up efficacy,and characteristics of lymph node ***,we comparatively analysed the lymph node metastasis rates at different *** variables are expressed as frequencies and percentages,and the analysis of difference was performed using theχ2 *** Bonferroni method was used for pairwise comparisons when statistical differences existed between multiple categorical *** A lymph node metastasis rate of 8.8%(55/623)was reported in patients with hepatic AE,with a female predilection(69.1%)and a statistically significant sex difference(χ2=8.018,P=0.005).Of the 55 patients with lymph node metastasis,72.7%had a parasite lesion,neighbouring organ invasion,and metastasis stage of P3N1M0 and above,of which 67.3%,78.2%,and 34.5%of hepatic AE lesions invaded the bile ducts,blood vessels,and distant metastases,*** rates of lymph node metastasis of 16.4%,21.7%,and 34.2%were reported for a preoperative abdominal ultrasound,magnetic resonance imaging,and computed tomography *** patients were intraoperatively suspected with enlarged lymph nodes and underwent radica

关键词： Echinococcosis Radical hepatectomy Lymph node metastasis Lymph node dissection Alveolar echinococcosis Hepatic

Coupling analysis method of grouting construction with deformation response of adjacent existing tunnel

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Underground Space 2024年第2期15卷 312-330页

作者： Ping-wei jiang Zhi-hong Zhang Hong Zheng Jin-kun Huang Key Laboratory of Urban Security and Disaster Engineering of China Ministry of Education Beijing University of TechnologyBeijing 100124China China MCC17 Group Co.LTD MaanshanAnhui 243000China School of Naval Architecture Ocean and Civil EngineeringShanghai Jiao Tong UniversityShanghai 200240China

In the new tunnel under close distance through the existing tunnel risk source,the grouting scheme developed to compensate for stratum losses is still based on empirical methods,relying on the overburden thickness of existing *** can potentially lead to an excessively high or low probability of uplift of existing *** a coupled deformation analysis method between the grouting construction and adjacent existing tunnels is of great theoretical significance for developing grouting *** order to reasonably limit the design parameters of grouting construction,based on the theory of fluid–solid coupling elastic pore-column expansion and the theory of random media,the calculation method of stratum displacement which simultaneously considers the coexistence of grout compaction expansion and permeability diffusion mode is derived,and the accuracy of the calculation method is verified by engineering *** accuracy of this calculation method was verified through engineering *** with the deformation coordination condition,the existing tunnel is regarded as an elastic Euler-Bernoulli continuous beam,and the finite element coupling balance equation of the interaction between the existing tunnel and the surrounding soil is *** on this,a coupling calculation model of the grouting construction and the deformation response of the adjacent existing tunnel is *** with three times of grouting construction examples in the shield tunneling project of Beijing Metro Line 12 under the existing airport line,the reliability of the coupling calculation model to determine the grouting construction parameters is *** calculation parameters in the coupling calculation model have clear physical meanings,which can provide a theoretical basis for the grouting design of similar risk source projects.

关键词： Grouting Close-range underpass Tunnel Random medium theory Euler-Bernoulli continuous beam

Effect of Al content on modification behavior of non-metallic inclusions in high-strength steel treated with rare earth

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Journal of Iron and Steel Research International 2024年第8期31卷 1886-1899页

作者： Zhan-peng tie Xue-yuan jiang Hai-yan Tang ·Gen Li Yu-hang Wang Jia-quan Zhang School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China Continuous Casting Business Section CISDI Engineering Co.Ltd.Chongqing 401122China Special Steel Institute Central Iron and Steel Research Institute Co.Ltd.Beijing 100081China

The influence of Al content(0.0053,0.0171,and 0.0578 wt.%)on the modification behavior of non-metallic inclusions in 20CrMoVTiB steel treated with rare earth elements was studied through high-temperature experiments and thermodynamic *** results showed that the modification products varied with the Al content in steel under 0.01 wt.%of Ce *** formation sequence of typical rare earth inclusions in steel with the increase in Al content was Ce_(2)O_(3)→CeAlO_(3)→CeAl_(11)O_(18),and the final stable products were highly Al content *** the Al content was 0.0053 wt.%,the stable phase in steel was Ce2O3;while the[Al]reached 0.0171 wt.%,the stable phase became CeA1O_(3).As the A1 content reached 0.0578 wt.%,CeAl_(11)O_(18) became the stable *** a result,increasing the Al content could inhibit the precipitation of Ce_(2)O_(3) inclusions in steel while promote the formation of CeAIO3 and CeAl_(11)O_(18) *** addition,both Ca treatment and Ce treatment could effectively refine the size of inclusions in steel by changing their ***,the feeding amount of Ca wire into molten steel should be appropriately reduced under the condition of adding Ce simultaneously,which is expected to be beneficial for an improved Ce treatment effect.

关键词： Rare earth Al content Steel Inclusion Thermodynamics Ca treatment