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Existence of Weakly Pandiagonal Orthogonal Latin Squares

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Acta Mathematica Sinica,English Series 2013年第6期29卷 1089-1094页

作者： Yong ZHANG wen LI Jian Guo lei College of Mathematics and Information Science Hebei Normal University

A weakly pandiagonal Latin square of order n over the number set {0, 1, . . . , n-1} is a Latin square having the property that the sum of the n numbers in each of 2n diagonals is the same. In this paper, we shall prove that a pair of orthogonal weakly pandiagonal Latin squares of order n exists if and only if n ≡ 0, 1, 3 （mod 4） and n≠3.

关键词： Latin square weakly pandiagonal Knut Vik design

Flexible CP-ABE Based Access Control on Encrypted Data for Mobile Users in Hybrid Cloud System

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Journal of Computer Science & Technology 2017年第5期32卷 974-990页

作者： wen-Min Li Xue-lei Li Qiao-Yan wen Shuo Zhang Hua Zhang State Key Laboratory of Networking and Switching Technology Beijing University of Posts and Telecommunications Beijing 100876 China

In hybrid cloud computing, encrypted data access control can provide a fine-grained access method for organizations to enact policies closer to organizational policies. This paper presents an improved CP-ABE (ciphertext-policy attribute-based encryption) scheme to construct an encrypted data access control solution that is suitable for mobile users in hybrid cloud system. In our improvement, we split the original decryption keys into a control key, a secret key and a set of transformation keys. The private cloud managed by the organization administrator takes charge of updating the transformation keys using the control key. It helps to handle the situation of flexible access management and attribute alteration. Meanwhile, the mobile user's single secret key remains unchanged as well as the ciphertext even if the data user's attribute has been revoked. In addition, we modify the access control list through adding the attributes with corresponding control key and transformation keys so as to manage user privileges depending upon the system version. Finally, the analysis shows that our scheme is secure, flexible and efficient to be applied in mobile hybrid cloud computing.

关键词： attribute-based access control hybrid cloud outsourcing computing attribute alteration data verification

MEDIASTINAL CAVERNOUS HEMANGIOMA:REPORT OF ONE CASE

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Chinese Medical Sciences Journal 2007年第1期22卷 69-70页

作者： Xue-zhong Xing wen-dong lei de-chao Zhang Jie He department of Thoracic Surgery Cancer Hospital （Institute） Chinese Academy of Medical Sciences ＆ Peking Union Medical College Beijing 100021

MEDIASTINAL cavernous hemangioma is a kind of primary mediastinal mesenchymal tumor that occurs rarely in any age. It was first reported by Shennon in 1914. In this study we reported a case of mediastinal cavernous he... 详细信息

关键词： hemangioma surgery chylothorax

Regulating the oxygen-atom configuration of carbon anode enabling extremely fast-charging potassium-ion hybrid capacitors

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Nano Research 2025年第1期18卷 373-381页

作者： Daping Qiu Yuehui Wang Lulu Zhang Hang lei Haizhou Ying Jin Niu Min Li Xuelin Yang Feng Wang Ru Yang Hubei Provincial Collaborative Innovation Center for New Energy Microgrid College of Electrical Engineering and New EnergyChina Three Gorges UniversityYichang 443002China State Key Laboratory of Chemical Resource Engineering Laboratory of Electrochemical Process and Technology for MaterialsBeijing University of Chemical TechnologyBeijing 100029China College of Materials and Chemical Engineering China Three Gorges UniversityYichang 443002China

Metal-ion hybrid capacitors,such as potassium-ion hybrid capacitors(PIHCs),are regarded as promising fast-charging energy storage ***,the kinetics mismatch between the battery anode and the capacitive cathode restricts their fastcharging *** constructing carbon anodes with enhanced kinetics is an innovative approach to address this ***,using epigallocatechin gallate with high oxygen content as the precursor,oxygen-enriched carbon materials(OEC)with tunable C=O content are successfully ***,the C=O content of OEC is regulated by adjusting the pyrolysis *** as an anode for PIHCs,OEC-600 with the highest C=O content exhibits an attractive fast-charging specific capacity of 135.2 mAh·g^(-1)at 20 A·g^(-1),along with a superior fast-charging cycling *** theoretical calculations,comprehensive kinetics analysis and in-situ Raman,the positive effects of C=O on the potassium storage capability and reversibility of OEC-600 are ***,PIHCs assembled based on an OEC-600 anode deliver impressive energy/power density of 145.1 Wh·kg^(-1)/45.9 kW·kg^(-1)and superior fast-charging cycling stability with 87.5%of capacity retention over 20,000 cycles at 5 A·g^(-1).This work is anticipated to provide an optional design concept toward the carbon anode for fast-charging PIHCs.

关键词： carbon anode oxygen epigallocatechin gallate potassium-ion hybrid capacitor

Mechanical Behaviour and Microstructure Evolution of Superplastic Mg-8.4 wt pct Li Alloy and Effect of Grain Size and Phase Ratio on Its Elongation

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Journal of Materials Science & Technology 2000年第1期16卷 55-58页

作者： Cao, FR Cui, JZ wen, JL lei, F Northeastern Univ Sch Met & Mat Dept Mat & Forming Control Shenyang 110006 Peoples R China

Mechanical properties and microstructure evolution of Mg-8.4 wt pet Li alloy have been investigated. The superplastic elongation-to-failure 920% at 573 K and initial strain rate of 5 x 10(-4) s(-1) at low nominal stress 2 MPa has been demonstrated. It was shown through optical microstructure that the average grain sizes at gauge length section before and after superplastic tension and at grip section were 7.5 mu m, 31.7 mu m and 20 mu m respectively, indicating significant deformation induced grain growth and static grain growth. Comparison of experiment data with published data for superplastic Mg-Li alloys shows that fine grain size and about 50 to 50 phase ratio contribute to achieving the largest superplasticity. Some related research works in other alloys are compiled and further evidences to such theoretic argument are provided.

关键词： Magnesium alloys

Effects of delta degrees of Freedom on Quark Condensate in Hot and dense Matter

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Chinese Physics Letters 1996年第11期13卷 813-816页

作者： LI lei NING Ping-zhi LI wen-qing department of Physics Nankai UniversityTianjin 300071 Normal School of Hengshui City HengshuiHebei 053000

The relativistic mean-field theory is applied to study the quark condensate systematically in nuclear matter at zero and finite temperature in terms of the relative importance of delta degrees of *** have included the high-order contributions to quark condensate in nuclear medium due to the baryon-baryon *** results are presented for the nuclear density up to five times larger than the normal density and temperature up to 120 *** is found that the delta resonance in nuclear matter can cause substantial decreases to in-medium quark condensate.

关键词： quark relativistic finite

基于第一性原理研究CO在C_(21)Si上的吸附

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原子与分子物理学报 2025年第5期42卷 22-26页

作者：张玲尹成斌杨蕾雷声马贝贝赵德永王远云南中烟工业有限责任公司技术中心昆明650231 西南林业大学机械与交通学院昆明650224

通过密度泛函理论(DFT)计算研究了单个CO分子分别在C_(21)Si上的吸附.由于结构中含有21个C原子以及引入一个Si原子,命名为(C_(21)Si).计算了体系中最稳定的几何结构、吸附能、吸附高度和态密度,研究了吸附的CO分子与基底之间的相互作用... 详细信息

通过密度泛函理论(DFT)计算研究了单个CO分子分别在C_(21)Si上的吸附.由于结构中含有21个C原子以及引入一个Si原子,命名为(C_(21)Si).计算了体系中最稳定的几何结构、吸附能、吸附高度和态密度,研究了吸附的CO分子与基底之间的相互作用.研究发现,当CO放置在C_(21)Si上吸附时,C原子靠近吸附优于O原子靠近时的吸附,吸附能分别为-0.86 eV和-0.36 eV,当O原子靠近吸时二者之间的吸附反应较弱,为物理吸附.C原子靠近时的吸附高度小,吸附反应更强,为化学吸附.根据态密度轨道之间的杂化程度,说明二者之间存在吸附反应,相较于O原子靠近吸附,基底对C原子靠近时的吸附能力更强,敏感度更高.

关键词： C_(21)Si 第一性原理 CO 吸附

Molecular mechanosensors in osteocytes

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Bone Research 2020年第2期8卷 115-138页

作者： lei Qin wen Liu Huiling Cao Guozhi Xiao Guangdong Provincial Key Laboratory of Cell Microenvironment and Disease Research Shenzhen Key Laboratory of Cell Microenvironmentand School of MedicineSouthern University of Science and TechnologyShenzhen 518055China

Osteocytes, the most abundant and long-lived cells in bone, are the master regulators of bone remodeling. In addition to their functions in endocrine regulation and calcium and phosphate metabolism, osteocytes are the major responsive cells in force adaptation due to mechanical stimulation. Mechanically induced bone formation and adaptation, disuse-induced bone loss and skeletal fragility are mediated by osteocytes, which sense local mechanical cues and respond to these cues in both direct and indirect ways. The mechanotransduction process in osteocytes is a complex but exquisite regulatory process between cells and their environment, between neighboring cells, and between different functional mechanosensors in individual cells. Over the past two decades, great efforts have focused on finding various mechanosensors in osteocytes that transmit extracellular mechanical signals into osteocytes and regulate responsive gene expression. The osteocyte cytoskeleton, dendritic processes, Integrin-based focal adhesions, connexin-based intercellular junctions, primary cilium, ion channels, and extracellular matrix are the major mechanosensors in osteocytes reported so far with evidence from both in vitro and in vitro studies. This review aims to give a systematic introduction to osteocyte mechanobiology, provide details of osteocyte mechanosensors, and discuss the roles of osteocyte mechanosensitive signaling pathways in the regulation of bone homeostasis.

关键词： cytes mec metabolism

Reduction of chromium oxides in stainless steel dust

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International Journal of Minerals,Metallurgy and Materials 2015年第6期22卷 573-581页

作者： Yan-ling Zhang wen-ming Guo Xin-lei Jia State Key Laboratory of Advanced Metallurgy University of Science and Technology Beijing

The recovery of metal oxides from stainless steel dust using C（graphite）, SiFe, and Al as reductants was investigated under various conditions. The apparent distribution ratio of Cr（L Cr ′^m/s ） in the recovered metal and residual slag phases was defined as the major performance metric. The results show that the recovery ratio of metals increases as the ratio of CaO ：SiO2 by mass in the residual slag increases to 1.17. The residual content of metals in the slag decreases as the Al2O3 content of the slag is increased from approximately 8wt% to 10wt%. The recovery ratio of Cr increases with increasing L Cr ′^ m/s , and a linear relationship between L Cr ′^m/s and the activity coefficient ratio of CrO in the slag and the recovered metal phase is observed. The combination of C and SiFe or Al as the reducing agents reveals that Si is the more effective coreductant.

关键词： stainless steel dust chromium oxides recovery apparent distribution ratio activity coefficient