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中国有色金属学会会刊：英文版 2006年第B2期16卷 439-443页

作者： liu Yu gong Xiao-lu Institut Charles Delaunay CNRS FRE 2848 LASMIS UTT 12 rue Marie Curie BP 2060 10010 Troyes France

Interpenetrating phase composites (IPCs) are a new class of composite materials with improved combinations of mechanical and physical properties. This study was performed on a new type of IPC called metal porous polymer composite (MPPC) with an interpenetrating network structure. Aluminum-polypropylene (AI-PE) and Aluminum-epoxy resin (Al-Ep) composites were produced by infiltrating the polymer in the aluminum foam. The composite microstructures were characterized using SEM observation. The compressive behavior and energy absorption characteristics of MPPC were investigated and compared with the aluminum foams. The compressive modulus of composite was compared with the VOIGT-REUSS bounds and HASHIN-SHTRIKMAN (H-S) bounds models. The experimental modulus of compressive tests falls well within the theoretical models.

关键词：金属多孔聚合物复合物互穿网络结构压缩行为能量吸收 MPPC复合物

Solid catalysts for the dehydrogenation of long-chain alkanes:lessons from the dehydrogenation of light alkanes and homogeneous molecular catalysis

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Science China Chemistry 2022年第11期65卷 2163-2176页

作者： Hongliu Wan Nengfeng gong Lichen liu Department of Chemistry Tsinghua UniversityBeijing 100084China State Key Laboratory of Coal Conversion Institute of Coal ChemistryChinese Academy of SciencesTaiyuan 030001China National Energy Center for Coal to Clean Fuels Synfuels China Co.Ltd.Beijing 101407China

Long-chain alkanes are abundant feedstocks supplied by natural resources and chemical industry. Specially, normal long-chain alkanes are primary products from Fischer-Tropsch synthesis(FTS) process, which is an important route for the utilization of coal in China. Facing a shift of energy nexus towards sustainable society, the conversion of long-chain alkanes derived from coal into value-added products(such as alkenes and oxygenates) is of great importance for securing China’s energy supply and the role transition of the commercial FTS plants from fuel makers to chemical suppliers. Among the potential transformation routes,the direct dehydrogenation of long-chain alkanes into alkenes is an attractive and practical route, due to the broad applications of long-chain alkenes(especially the linear α-olefins). In this review, we will summary the key insights obtained from the literature on the dehydrogenation of light alkanes based on supported metal catalysts and the dehydrogenation of alkanes with homogeneous molecular catalysts and then discuss how to translate these lessons into the development of efficient catalysts and processes for the dehydrogenation of long-chain alkanes into long-chain alkenes.

关键词： long-chain alkanes catalytic dehydrogenation α-olefins subnanometric cluster zeolite

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Controlled WISP-1 shRNA Delivery Using Thermosensitive Biodegradable Hydrogel in the Treatment of Osteoarthritis

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Journal of Bionic Engineering 2015年第2期12卷 285-293页

作者： gong Yubao Ma Hecheng liu Jianguo Department of Bone and Joint First Hospital of Jilin University Changchun 130021 China

This paper presents a new method of delivering shRNA with biodegradable, thermosensitive PLGA-PEG-PLGA hydrogels for gene treatment of osteoarthritis （OA）. OA is a chronic debilitating disease. Without the proper treatment and prognosis, it may result in the loss of joint function in aged people. Currently, gene therapy targeted on WISP-1 has emerged as an alternative method for OA treatment. In order to constantly release shRNA at 37.0 ℃, we synthetized the hydrogels via ring-opening copolymerization of lactide （LA） and glycolide （GA） using Polyethylene glycol （PEG Mn = 1000） and stannous octoate （Sn（Oct）2, 95%） as the macroinitiator and catalyst. First, the PLGA-PEG-PLGA copolymer was mixed with WISP- 1 shRNA and PEI-Lys in distilled water at 4.0 ℃. Then, the WISP-lshRNA/PEI-Lys loaded hydrogel was formed after incubation of the mixed solution at 37.0 ℃. During tests, the plasmid was released from this hydrogel complex constantly, and enhanced the transfection efficiency of WISP-1 shRNA. In addition, silencing WISP-1 results to lower expression of MMP-3 and ADAMTS, and the accumulation of HBP 1 in synoviocytes. Therefore, the hydrogel containing WISP-1 shRNA is demonstrated an efficient way for the treatment of OA.

关键词： osteoarthritis biodegradable thermosensitive hydrogel PLGA-PEG-PLGA WISP-1

Abnormal changes of dynamic derivatives at low reduced frequencies

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Chinese Journal of Aeronautics 2018年第7期31卷 1428-1436页

作者： Weiwei ZHANG Yiming gong Yilang liu School of Aeronautics Northwestern Polytechnical University

A number of studies have found that abnormal changes of dynamic derivatives occurred at very low reduced frequencies, but its inducement mechanism is not very clear. This paper has researched the abnormal changes and analyzed the influence on some parameters by solving the unsteady flow around forced oscillation airfoils based on Navier-Stokes equations. Results indicate that when the reduced frequency approaches to zero, the dynamic derivatives obtained by the numerical method will diverge. We have also proven it in theory that this phenomenon is not physical but completely caused by numerical singularity. Furthermore, the abnormal phenomenon can be effectively mitigated by using the time spectral method to solve the aerodynamic forces and the integral method to obtain the dynamic derivatives. When the reduced frequency is in the range of 0.001–0.01, the dynamic derivative maintains nearly unchanged for the whole speed region. This study can provide a reference for the reasonable choice of the reduced frequency in calculations and experiments of dynamic derivatives.

关键词： Dynamic derivatives Numerical diverge Reduced frequency Time spectral method Unsteady flow

An innovative flake graphite upgrading process based on HPGR,stirred grinding mill, and nanobubble column flotation

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International Journal of Mining Science and Technology 2021年第6期31卷 1063-1074页

作者： Fangyuan Ma Dongping tao Youjun tao Shuyong liu Key Laboratory of Coal Processing and Efficient Utilization of Ministry of Education School of Chemical Engineering and TechnologyChina University of Mining and TechnologyXuzhou 221116China School of Resources and Environmental Engineering Shandong University of TechnologyZibo 255049China School of Mining Engineering University of Science&Technology LiaoningAnshan 114051China

Physical upgrading of graphite is typically achieved with many stages of grinding and flotation to produce a concentrate with approximately 95% carbon *** innovative grinding and column flotation process has been developed for efficient graphite upgrading to substantially simplify the process flowsheet and reduce operating *** this process,a high-pressure grinding roller(HPGR) and a stirred mill were employed as primary comminution techniques and a nanobubble flotation column as a key separation *** results obtained with a crystalline flake graphite sample with a carbon grade of 11.15% show that the novel process can produce a concentrate with 94.82% carbon grade and 97.89% recovery from an open circuit of one rougher and two cleaner flotation *** electron microscope(SEM)microphotographs indicate that HPGR offers the advantage of more effective protection of graphite flakes during *** test results show that stirred mill could not only protect graphite flakes but also promote the efficient liberation of *** with the traditional flotation process,nanobubble flotation can effectively recover ultrafine *** new process possesses a number of important advantages over the traditional method,including substantially higher graphite recovery,greatly simplified process flowsheet,better protection of flake size,reduced reagent consumption and process costs,etc.

关键词： Column flotation Graphite HPGR Microbubbles Nanobubbles Stirred mill

Automatic Search of Threshold Implementations of 4-Bit S-Boxes Resisting DPA

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Chinese Journal of Electronics 2017年第1期26卷 93-100页

作者： liu Bozhong gong Zheng QIU Weidong School of Information Security Shanghai Jiao Tong University School of Computer Science South China Normal University State Key Laboratory of Information Security Institute of Information Engineering Chinese Academy of Sciences

The threshold implementation method of Substitution box(S-box) has been proposed by Nikova et al. for resisting first-order Differential power attacks with glitches. To lower the time complexity for a threshold implementation of a specific non-linear function, one needs to decompose the function first and then search possible share methods for it. However, the time complexity for this search process is still non-trivial. In this paper, an effective method of searching threshold implementations of4-bit S-boxes is proposed. It mainly consists of two *** the decomposing stage, an efficient way of decomposing an S-box is introduced. For the sharing stage, the search complexity is lowered by the technique of time memory trade-off. As a result, threshold implementations of various lightweight block ciphers’ S-boxes are given. Moreover, our method is applied to each 4-bit involutive S-box and some candidates of threshold implementations are presented.

关键词： S-box Differential power attacks Threshold implementation Time memory trade-off

Image categorization using a semantic hierarchy model with sparse set of salient regions

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Frontiers of Computer Science 2013年第6期7卷 838-851页

作者： Chunping liu Yang ZHENG Shengrong gong School of Computer Science and Technology Soochow University Suzhou 215006 China The Second Hospital of Nanjing Nanjing 210003 China

Image categorization in massive image database is an important problem. This paper proposes an approach for image categorization, using sparse set of salient semantic information and hierarchy semantic label tree （HSLT） model. First, to provide more critical image semantics, the proposed sparse set of salient regions only at the focuses of visual attention instead of the entire scene was formed by our proposed saliency detection model with incorporating low and high level feature and Shotton＇s semantic texton forests （STFs） method. Second, we also propose a new HSLT model in terms of the sparse regional semantic information to automatically build a semantic image hierarchy, which explicitly encodes a general to specific image relationship. And last, we archived image dataset using image hierarchical semantic, which is help to improve the performance of image organizing and browsing. Extension experimefital results showed that the use of semantic hierarchies as a hierarchical organizing frame- work provides a better image annotation and organization, improves the accuracy and reduces human＇s effort.

关键词： salient region sparse set semantic hierarchy image annotation image categorization

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扭曲双层石墨烯的层间电导特性研究

原子与分子物理学报 2025年第6期42卷 83-88页

作者：陶懿洲刘超方贺男南京邮电大学电子与光学工程学院南京210023

扭曲双层石墨烯(TBG)由于具有莫特绝缘和非常规超导等新奇的电学特性,在纳米技术领域存在巨大的应用潜力.本文基于光学衍射物理方法,构建了一个适用于TBG的理论模型,并利用该理论模型研究了TBG的层间电导特性.研究结果较好地解释了TBG... 详细信息

扭曲双层石墨烯(TBG)由于具有莫特绝缘和非常规超导等新奇的电学特性,在纳米技术领域存在巨大的应用潜力.本文基于光学衍射物理方法,构建了一个适用于TBG的理论模型,并利用该理论模型研究了TBG的层间电导特性.研究结果较好地解释了TBG层间电导随扭转角变化的实验结果,并阐明了其物理机制.此外,本文还计算了电极参数、隧穿层厚度以及界面势强度等物理因素对层间电导特性的影响.计算结果表明:随着电极化学势的增大,层间电导关于扭转角的变化曲线近似整体向上平移;层间电导随着上层隧穿层厚度的增加而衰减并趋于稳定,而随着下层隧穿层厚度振荡;TBG两层扭转石墨烯的界面势强度越强,则层间电导随扭转角下降得越快.

关键词：低维物理层间电导光学衍射方法扭曲双层石墨烯

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Protection effect of Xuanfudaizhetang on reflux esophagitis in rats

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Asian Pacific Journal of Tropical Medicine 2014年第4期7卷 267-270页

作者： Bing Liang Zhong-Hua liu Hai-tao Wei Zhi Zhang gong-Ning Shi Department of Cardiothoracic Surgery Huahe HospitalHenan University Medical College Henan University

Objective:To study protection effect of Xuanfudaizhetang on reflux esophagitis in ***:A total of 50 Wistar rats were randomly divided into groups A,B,C,D and E with 10 in *** esophagitis model in rats was established by incomplete helicobacter seam+lower esophagus *** rats were divided into 5 groups:group A as control group,group B as model group,group C with saline lavage treatment,group D with motilium treatment,group E with Xuanfudaizhetang lavage *** of esophageal,gastric mucosa and pH changes of rats were compared between ***:Weight gain in group D and E was significantly higher in than group C;the esophageal mucosa grades and esophagus tissue pathological morphology grades of group D and E were higher than that of group B and C with significant difference between groups(P<0.05);pH of lower esophageal mucosa in group D and E increased significantly than that in the group B and C(P<0.05),and the distal mucosal pH dropped significantly in the group B and C(P<0.05).Conclusions:Xuanfudaizhetang can obviously improve the pH of lower esophageal mucosa in rats with reflux esophagitis,decrease pH value of gastric mucosal,thus improve esophageal mucosa pathological conditions to achieve therapeutic effect on reflux esophagitis.

关键词： Xuanfudaizhetang Reflux esophagitis Esophageal mucosa PH value Treatment

Molecular Structure Tailoring of Organic Spacers for High‑Performance Ruddlesden–Popper Perovskite Solar Cells

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Nano-Micro Letters 2025年第2期17卷 314-357页

作者： Pengyun liu Xuejin Li Tonghui Cai Wei Xing Naitao Yang Hamidreza Arandiyan Zongping Shao Shaobin Wang Shaomin liu School of Materials Science and Engineering State Key Laboratory of Heavy Oil ProcessingChina University of Petroleum(East China)Qingdao 266580People’s Republic of China School of Chemistry and Chemical Engineering Shandong University of TechnologyZibo 255049People’s Republic of China Centre for Applied Materials and Industrial Chemistry(CAMIC) School of ScienceRMIT UniversityMelbourneVic 3000Australia WA School of Mines:Minerals Energy and Chemical Engineering(WASM‑MECE)Curtin UniversityPerthWA 6102Australia School of Chemical Engineering The University of AdelaideAdelaideSA 5005Australia School of Engineering Great Bay UniversityDongguan 523000People’s Republic of China

Layer-structured Ruddlesden–Popper(RP)perovskites(RPPs)with decent stability have captured the imagination of the photovoltaic research community and bring hope for boosting the development of perovskite solar cell(PSC)***,two-dimensional(2D)or quasi-2D RP PSCs are encountered with some challenges of the large exciton binding energy,blocked charge transport and poor film quality,which restrict their photovoltaic ***,these issues can be readily resolved by rationally designing spacer cations of *** review mainly focuses on how to design the molecular structures of organic spacers and aims to endow RPPs with outstanding photovoltaic *** firstly elucidated the important roles of organic spacers in impacting crystallization kinetics,charge transporting ability and stability of *** we brought three aspects to attention for designing organic ***,we presented the specific molecular structure design strategies for organic spacers of RPPs aiming to improve photovoltaic performance of RP *** proposed strategies in this review will provide new avenues to develop novel organic spacers for RPPs and advance the development of RPP photovoltaic technology for future applications.

关键词： Ruddlesden-Popper perovskites Low-dimensional perovskite solar cells Organic spacers Molecular structure Design strategies