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International Journal of Minerals,Metallurgy and Materials 2013年第7期20卷 684-692页

作者： ya-jun su Xin-hua Liu Yong-fu Wu Hai-you Huang Jian-xin Xie Key Laboratory for Advanced Materials Processing (Ministry of Education) Institute of Advanced Materials and Technology Uni- versity of Science and Technology Beijing

The steady-state temperature field of horizontal core-filling continuous casting （HCFC） for producing copper cladding aluminum rods was simulated by finite element method to investigate the effects of key processing parameters on the positions of solid-liquid interfaces （SLIs） of copper and aluminum. It is found that mandrel tube length and mean withdrawing speed have significant effects on the SLI positions of both copper and aluminum. Aluminum casting temperature （TAI）（1003-1123 K） and secondary cooling water flux （600-900 L.h-1） have little effect on the SLI of copper but cause the SLI of aluminum to move 2-4 mm. When TA1 is in a range of 1043-1123 K, the liquid aluminum can fill continuously into the pre-solidified copper tube. Based on the numerical simulation, reasonable processing parameters were determined.

关键词： metal cladding copper aluminum continuous casting interfaces computer simulation

Liquid crystal character controlled by complementary discotic molecules mixtures： Columnar stacking type and mesophase temperature range

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Chinese Chemical Letters 2016年第3期27卷 475-480页

作者： yan Li Ming-Guang Li ya-jun su Jian-Gang Liu yan-Chun Han Shi-jun Zheng Li-Xiang Wang State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun 130022 China University of the Chinese Academy of Sciences Beijing 100049 China School of Materials Science and Engineering Zhengzhou University Zhengzhou 450052 China

In this work, the mesophase properties were tuned via mixing two discotic molecules with structural complementarity. Compared with the liquid crystalline hexakis（n-hexyloxy）triphenylene（H6TP）materials（columnar hexagonal phase from 53 ℃ to 91 ℃）, mesophase types as well as phase transition temperatures varied with the introduction of crystalline hexaazatriphenylene derivative（PBH）molecules. The introduction of less than 33% amount of PBH disrupted the columnar hexagonal phase formed by H6 TP remarkably, followed by the decreased clearing temperatures of liquid crystals. As the PBH amount was further increased, the destroyed columnar hexagonal phase was turned into the columnar rectangular phase, in which H6 TP and PBH molecules together formed the columnar mesophase. The formation of new mesophase contributed to the enlarged mesophase temperature（from44 ℃ to 144 ℃）. We speculated that the alkyl chains interaction induced by the PBH component competed with the strong p–p stacking between H6 TP molecules, thus altering the liquid crystalline properties including mesophase types and phase transition temperatures.

关键词： Alkyl chains packing Mesophase type Liquid crystals Phase transitions Mixture

Synthesis dibromo substituted BOPHY dye for the singlet oxygen generation

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Chinese Chemical Letters 2016年第2期27卷 190-194页

作者： Tian-Fang Cui Jing Zhang Xin-Dong Jiang ya-jun su Chang-Liang sun Jiu-Li Zhao College of Applied Chemistry Key Laboratory of Rare-earth Chemistry and Applying Liaoning Province Shenyang University of Chemical Technology Center of Physical and Chemistry Test Shenyang University of Chemical Technology

A dibromo substituted BOPHY derivative（2） was prepared and found to exhibit photo-sensitization capability. Rapid oxidation of 80% DPBF at the first 6 min was observed suggesting that 2 is a superior photo-sensitizer than methylene blue. The HOMO-LUMO band gap for the lowest energy absorption bands of the BOPHY 1 is smaller than that of PS 2, which is in good agreement with the red shift in the absorption observed between 1 and 2.

关键词： BOPHY Singlet oxygen Photosensitizer Photophysical property DFT

Fabricating functionally graded Fe-Cr-Co permanent magnetic alloys via laser powder bed fusion

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Journal of Iron and Steel Research(International) 2024年第3期31卷 729-737页

作者： ya-zhou He ya-qing Hou Peng Shen Hao Zhang Dong Zhou Hang su Central Iron and Steel Research Institute Co. Ltd.Beijing 100081China Material Digital R&D Center China Iron and Steel Research Institute Group Co.Ltd.Beijing 100081China

Laser powder bed fusion(LPBF)in-situ alloying technology offers the possibility to construct gradient materials with varied structures and properties.Functionally graded Fe-Cr-Co permanent magnetic alloys were fabricated by LPBF and in-situ alloying mixed powders of Fe,Cr,and Co elements.The effects of different Fe,Cr and Co contents on the microstructure,magnetic properties and hardness of Fe-Cr-Co alloys prepared by LPBF were studied.The as-built Fe-Cr-Co alloys present a single body-centered-cubic phase and have a homogeneous distribution of elements.The mechanical properties and magnetic properties of the compositionally graded sample show a gradient variation.With the increase in Cr content,the Vickers hardness of the sample increases,and the saturation magnetization of the sample decreases.The optimal magnetic properties in an isotropic state are given as coercivity HcB=21.65 kA/m,remanence Br=0.70 T and energy product(BH)_(max)=5.35 kJ/m^(3),which are comparable to or higher than the reported magnetic properties in an isotropic state prepared by traditional powder metallurgy.LPBF in-situ alloying technology has the potential to further explore Fe-Cr-Co magnetic materials,such as those consisting of multiple or more constituent elements,and to maximize the compositional flexibility of magnetic materials.

关键词： Fe-Cr-Co alloy Laser powder bed fusion In-situ alloying Functional material Magnetic property

Erythrodermic mycosis fungoides: A case report

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World Journal of Clinical Cases 2024年第1期12卷 130-135页

作者： Wu-Bing Xu ya-Ping Zhang su-Ping Zhou Hao-yang Bai Department of Radiology Shaoxing People’s HospitalKey Laboratory of Functional Molecular Imaging of Tumor and Interventional Diagnosis and Treatment of Shaoxing CityShaoxing 312000Zhejiang ProvinceChina

BACKGROUND Mycosis fungoides is the most common primary cutaneous T-cell lymphoma,whereas generalized erythroderma is rare.In this report,we describe a case of mycosis fungoides with generalized erythroderma using complete clinical data and[18F]fluoroDglucose positron emission tomography/computed tomography(18F-FDG PET/CT)images.CASE suMMARY Systemic skin redness with desquamation for three years confirmed mycosis fungoides within one month.The patient underwent left axillary lymphadenectomy biopsy;pathological biopsy suggested abnormal T-cell lesions consistent with mycosis fungoides involving lymph nodes.The patient received methotrexate,5 mg twice weekly,as part of their chemotherapy regimen.Patients January half after discharge,no obvious cause of high fever,left axillary lymph nodes with red heat pain,and rupture entered our hospital for treatment.CONCLUSION The 18F-FDG PET/CT is essential for early diagnosis and timely treatment.

关键词： Mycosis fungoides Positron emission tomography/computed tomography Imaging Diagnosis Differential diagnosis Treatment Case report

Iterative physical optics method based on efficient occlusion judgment with bounding volume hierarchy technology

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Journal of Electronic Science and Technology 2024年第1期22卷 1-12页

作者： yang su Yu-Mao Wu jun Hu Key Laboratory for Information Science of Electromagnetic Waves(MoE) School of Information Science and TechnologyFudan UniversityShanghai200433China School of Electronic Science and Engineering University of Electronic Science and Technology of ChinaChengdu611731China

This paper builds a binary tree for the target based on the bounding volume hierarchy technology,thereby achieving strict acceleration of the shadow judgment process and reducing the computational complexity from the original O(N^(3))to O(N^(2)logN).Numerical results show that the proposed method is more efficient than the traditional method.It is verified in multiple examples that the proposed method can complete the convergence of the current.Moreover,the proposed method avoids the error of judging the lit-shadow relationship based on the normal vector,which is beneficial to current iteration and convergence.Compared with the brute force method,the current method can improve the simulation efficiency by 2 orders of magnitude.The proposed method is more suitable for scattering problems in electrically large cavities and complex scenarios.

关键词： Bounding volume hierarchy Cavity scattering Iterative physical optics(IPO)

Understanding adversarial attacks on observations in deep reinforcement learning

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Science China(Information Sciences) 2024年第5期67卷 69-83页

作者： You QIAOBEN Chengyang YING Xinning ZHOU Hang su jun ZHU Bo ZHANG Department of Computer Science and Technology Beijing National Research Center for Information Science and Technology Tsinghua-Bosch Joint Center for Machine Learning Institute for Artificial Intelligence Tsinghua University Peng Cheng Laboratory

Deep reinforcement learning models are vulnerable to adversarial attacks that can decrease the cumulative expected reward of a victim by manipulating its observations. Despite the efficiency of previous optimization-based methods for generating adversarial noise in supervised learning, such methods might not achieve the lowest cumulative reward since they do not generally explore the environmental dynamics.Herein, a framework is provided to better understand the existing methods by reformulating the problem of adversarial attacks on reinforcement learning in the function space. The reformulation approach adopted herein generates an optimal adversary in the function space of targeted attacks, repelling them via a generic two-stage framework. In the first stage, a deceptive policy is trained by hacking the environment and discovering a set of trajectories routing to the lowest reward or the worst-case performance. Next, the adversary misleads the victim to imitate the deceptive policy by perturbing the observations. Compared to existing approaches, it is theoretically shown that our adversary is strong under an appropriate noise level. Extensive experiments demonstrate the superiority of the proposed method in terms of efficiency and effectiveness, achieving state-of-the-art performance in both Atari and MuJoCo environments.

关键词： deep learning reinforcement learning adversarial robustness adversarial attack

Transient receptor potential vanilloid 1 involved in the analgesic effects of total flavonoids extracted from Longxuejie(Resina Dracaenae Cochinchinensis)

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Journal of Traditional Chinese Medicine 2024年第3期44卷 437-447页

作者： MO Xiaoqiang CHEN yating YIN Qian CHEN Haibo BAN Qiang LI jun CHEN su yaO Jinguang Department of Stomatology Affiliated Hospital of Youjiang Medical University for Nationalities College of General Practitioners Youjiang Medical University for Nationalities College of Biomedical Engineering South-Central Minzu UniversityKey Laboratory of Cognitive Science of State Ethnic Affairs CommissionHubei Key Laboratory of Medical Information Analysis and Tumor Diagnosis and Treatment College of Pharmacy South-Central Minzu University

OBJECTIVE: To evaluate the analgesic effects of total flavonoids of Longxuejie(Resina Dracaenae Cochinchinensis)(TFDB) and explore the possible analgesic mechanism associated with transient receptor potential vanilloid 1(TRPV1).METHODS: Whole-cell patch clamp technique was used to observe the effects of TFDB on capsaicin-induced TRPV1 currents. Rat experiments in vivo were used to observe the analgesic effects of TFDB. Western blot and immunofluorescence experiments were used to test the change of TRPV1 expression in DRG neurons induced by TFDB.REsuLTS: Results showed that TFDB inhibited capsaicin-induced TRPV1 receptor currents in acutely isolated dorsal root ganglion(DRG) neurons of rats and the half inhibitory concentration was(16.7 ± 1.6) mg/L.TFDB(2-20 mg/kg) showed analgesic activity in the phase Ⅱ of formalin test and(0.02-2 mg per paw)reduced capsaicin-induced licking times of rats. TFDB(20 mg/kg) was fully efficacious on complete Freund's adjuvant(CFA)-induced inflammatory thermal hyperalgesia and capsaicin could weaken the analgesic effects. The level of TRPV1 expressions of DRG neurons was also decreased in TFDB-treated CFA-inflammatory pain rats.CONCLUSION: All these results indicated that the analgesic effect of TFDB may contribute to their modulations on both function and expression of TRPV1 channels in DRG neurons.

关键词： Freund's adjuvant Longxuejie () capsaicin flavonoids formaldehyde inflammatory pain transient receptor potential vanilloid 1

P-and SV-wave dispersion and attenuation in saturated microcracked porous rock with aligned penny-shaped fractures

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Petroleum Science 2024年第1期21卷 143-161页

作者： Sheng-Qing Li Wen-Hao Wang Yuan-Da su jun-Xin Guo Xiao-Ming Tang School of Geosciences China University of Petroleum(East China)Qingdao 266580ShandongChina Laoshan National Laboratory Qingdao 266071ShangdongChina Guangdong Provincial Key Laboratory of Geophysical High-resolution Imaging Technology Southern University of Science and TechnologyShenzhen 518055GuangdongChina Department of Earth and Space Sciences Southern University of Science and TechnologyShenzhen 518055GuangdongChina

P-and SV-wave dispersion and attenuation have been extensively investigated in saturated poroelastic media with aligned fractures.However,there are few existing models that incorporate the multiple wave attenuation mechanisms from the microscopic scale to the macroscopic scale.Hence,in this work,we developed a unified model to incorporate the wave attenuation mechanisms at different scales,which includes the microscopic squirt flow between the microcracks and pores,the mesoscopic wave-induced fluid flow between fractures and background(FB-WIFF),and the macroscopic Biot's global flow and elastic scattering(ES)from the fractures.Using Tang's modified Biot's theory and the mixed-boundary conditions,we derived the exact frequency-dependent solutions of the scattering problem for a single penny-shaped fracture with oblique incident P-and SV-waves.We then developed theoretical models for a set of aligned fractures and randomly oriented fractures using the Foldy approximation.The results indicated that microcrack squirt flow considerably influences the dispersion and attenuation of P-and SV-wave velocities.The coupling effects of microcrack squirt flow with the FB-WIFF and ES of fractures cause much higher velocity dispersion and attenuation for P waves than for SV waves.Randomly oriented fractures substantially reduce the attenuation caused by the FB-WIFF and ES,particularly for the ES attenuation of SV waves.Through a comparison with existing models in the limiting cases and previous experimental measurements,we validated our model.

关键词： Aligned fractures P-and SV-wave Dispersion and attenuation Microcracked porous background FB-WIFF Elastic scattering Squirt flow

Evolution exploration and structure prediction of Keggin-type group IVB metal-oxo clusters

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Chinese Chemical Letters 2024年第5期35卷 487-492页

作者： Run-Han Li Tian-Yi Dang Wei Guan Jiang Liu ya-Qian Lan Zhong-Min su School of Chemistry South China Normal UniversityGuangzhou 510006China Institute of Functional Material Chemistry Faculty of ChemistryNortheast Normal UniversityChangchun 130024China Institute of Theoretical Chemistry Jilin UniversityChangchun 130023China

The fascinating chemical structure and broad application prospect of Keggin-type polyoxometalates(POMs)have attracted many chemists to explore and discover continuously.Unlike the traditional Keggin,larger metal atomic radius,higher metal coordinated numbers,lower metal valence states and other features allow the group IVB metal-based Keggin(IVB-Keggin)more space and unknown in terms of structure and performance.Herein,density functional theory(DFT)calculations were performed to explore the influences including cores,shells,caps,and terminal ligands,et al.on IVB-Keggin,and analyze the possibility of novel structure synthesis.From the perspective of multi-layer onion-like clusters,molecular energy level,host-guest interaction energy,surface charge and covalent bond polarity can be further adjusted to achieve the oriented design of functional IVB-Keggin.These insights are expected to provide theoretical support for experimental synthesis,opening a new perspective to understand the growth of Keggin.

关键词： Keggin Metal-oxo clusters Group IVB Onion pattern DFT