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A judicious approach to induce large size growth of hydroxyapatite via applying graphene modified silicon nitride nanowires

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Journal of Materiomics 2024年第2期10卷 490-498页

作者： Lina Sun Leilei zhang ruonan zhang Hejun Li State Key Laboratory of Solidification Processing Shanxi Key Laboratory of Fiber Reinforced Light Composite MaterialsNorthwestern Polytechnical UniversityXi'an710072China

Mimicking the structure of natural bone collagen fibers/hydroxyapatite(HA)to synthesize large size of HA for accelerated bone repair remains a ***,silicon nitride nanowires(SN)-graphene(GE)was designed by the chemical vapor deposition,forming SN-GE(SG)similar to collagen ***,the large size HA was assembled onto SG by pulsed electrochemical deposition,the SG/HA(SGH)mimics the collagen fibers/HA structure of *** introduction of SG induces HA to large size grow in the form of *** can be grown on a large size inextricably with the existence of GE modified *** the one hand,the upright GE sheets effectively increases the surface roughness which enhances the nucleation site of *** the other hand,the C=O provides chemical bonding and induces HA *** with SN/HA(SH),the porosity of SGH decreased by 71%.The average diameter of the SGH is(9.76±0.25)*** with SH,the diameter of SGH is 22 times larger than the diameter of *** that SG induces large size growth of *** work can provide a general strategy for the efficient preparation of biological scaffolds with large size HA that can be used in bone tissue engineering.

关键词： Hydroxyapatite Graphene Large size Silicon nitride nanowires Bone tissue engineering

Joint position optimization,user association,and resource allocation for load balancing in UAV-assisted wireless networks

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Digital Communications and Networks 2024年第1期10卷 25-37页

作者： Daosen Zhai Huan Li Xiao Tang ruonan zhang Haotong Cao School of Electronics and Information Northwestern Polytechnical UniversityXian710072China State Key Laboratory of Integrated Services Networks Xidian UniversityXian710071China Department of Computing Hong Kong Polytechnic UniversityHong Kong SARChina

Unbalanced traffic distribution in cellular networks results in congestion and degrades spectrum *** tackle this problem,we propose an Unmanned Aerial Vehicle(UAV)-assisted wireless network in which the UAV acts as an aerial relay to divert some traffic from the overloaded cell to its adjacent underloaded *** fully exploit its potential,we jointly optimize the UAV position,user association,spectrum allocation,and power allocation to maximize the sum-log-rate of all users in two adjacent *** tackle the complicated joint optimization problem,we first design a genetic-based algorithm to optimize the UAV ***,we simplify the problem by theoretical analysis and devise a low-complexity algorithm according to the branch-and-bound method,so as to obtain the optimal user association and spectrum allocation *** further propose an iterative power allocation algorithm based on the sequential convex approximation *** simulation results indicate that the proposed UAV-assisted wireless network is superior to the terrestrial network in both utility and throughput,and the proposed algorithms can substantially improve the network performance in comparison with the other schemes.

关键词： Load balance Unmanned aerial vehicle Userassociation Resource management

Liver fibrosis： mechanisms of immune-mediated liver injury

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Cellular & Molecular Immunology 2012年第4期9卷 296-301页

作者： ruonan Xu Zheng zhang Fu-Sheng Wang Liver Disease Research Center for Biological Therapy Beijing 302 Hospital Beijing China

Liver fibrosis and its end-stage consequence, cirrhosis, represent the final common pathway of virtually all chronic liver diseases. Research into hepatic stellate cell activation, imbalance of the extracellular matrix synthesis and degradation and the contribution of cytokines and chemokines has further elucidated the mechanisms underlying fibrosis. Furthermore, clarification of changes in host adaptive and innate immune systems has accelerated our understanding of the association between liver inflammation and fibrosis. Continued elucidation of the mechanisms of hepatic fibrosis has provided a comprehensive model of fibrosis progression and regression. This review summarizes the current concepts of improvements that have been made in the field of fibrosis.

关键词： cirrhosis hepatic stellate cell liver fibrosis

From borophosphate to fluoroborophosphate:a rational design of fluorine-induced birefringence enhancement

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Science China Chemistry 2021年第9期64卷 1498-1503页

作者： Wenyao zhang Zhizhong zhang Wenqi Jin ruonan zhang Meng Cheng Zhihua Yang Shilie Pan CAS Key Laboratory of Functional Materials and Devices for Special Environments Xinjiang Technical Institute of Physics&ChemistryCASXinjiang Key Laboratory of Electronic Information Materials and DevicesUrumqi830011China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing100049China

The introduction of oxofluoride anion into anionic group assists to tune optical properties owing to the change of coordination,electronegativity,and according anionic ***,we proposed a rational design of new compounds by fluorine-driven structure and optical property evolution.A new borophosphate Ba_(2)BP_(3)O_(11)with the monoclinic space group P2_(1/c) has been synthesized in the sealed ***_(2)BP_(3)O_(11)exhibits a rare P-O-P bridge formation,which is the first example in alkaline-earth metal *** further substituting[BO_(4)]^(3-)with[BO_(3)F]^(4-),the first alkaline-earth metal/lead fluoroborophosphates M_(2)BP_(2)O_(8)F(M=Ba and Pb)with the same space group were *** the scissors effect of fluorine,in M_(2)BP_(2)O_(8)F(M=Ba and Pb),a BO_(3)F tetrahedron corner-sharing with three PO_(4)tetrahedra forms 1D chains along the b-axial direction,which are filled by MO_(n)(M=Ba/Pb,n=5,6,8)distorted *** first principles calculation shows that the borophosphate Ba_(2)BP_(3)O_(11)has a birefringence about 0.013@1,064 nm,while the fluoroborophosphates M_(2)BP_(2)O_(8)F(M=Ba and Pb)have the values of 0.035 and 0.043@1,064 nm,*** an apparent enhancement in birefringence is derived from synergies of the oxyfluoride and *** introduction of fluorine-containing heteroanionic groups provides a feasible strategy to design novel promising optical materials.

关键词： borophosphate fluoroborophosphates P-O-P bridges formation birefringence

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Thermal insulating and fire-retardant Si_(3)N_(4) nanowire membranes resistant to high temperatures up to 1300℃

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Journal of Materials Science & Technology 2023年第24期155卷 82-88页

作者： Yeye Liu Leilei zhang ruonan zhang Siqi Shao Lina Sun Xinyi Wan Tiantian Wang State Key Laboratory of Solidification Processing Shaanxi Key Laboratory of Fiber Reinforced Light Composite MaterialsNorthwestern Polytechnical UniversityXi’an 710072China

Superior thermal insulating and fire-retardant ceramic membranes are urgently demanded in the aerospace,construction,and chemical engineering ***,the generic characteristics of ceramic membranes,such as brittleness,structural collapse,and crystallization-induced pulverization behavior,present a great plague to their practical ***,we report a highly flexible,mechanically stable,fire-retardant,and high-temperature-resistant ceramic membrane based on the interlocked Si_(3)N_(4) nanowires formed by the precursor pyrolysis *** Si_(3)N_(4) nanowire membrane(SNM)has excellent high-temperature resistance under alcohol lamps and butane spray *** thermal insulation with a thermal conductivity as low as 0.056 W m^(-1)K^(-1)can be attributed to the high porosity of SNM,which makes it a desirable candidate for heat insulators under harsh *** importantly,SNM exhibits thermal stability and robust mechanical properties in the range of 25 to 1300℃.The high-temperature resistance of SNM up to 1300℃is achieved by the four stages:Si3 N4 nanowires,Si_(3)N_(4)@SiO_(2) nanowires,SiO_(2) nanowires,and bead-like SiO_(2) *** heat-treated at 1300℃,the macroscopic size of SNM does not change significantly,and the interlocked structure is still ***,SNM still maintains excellent mechanical properties,with tensile strength as high as 0.26 *** work provides a facile method for fabricating excellent thermal insulating and fire-retardant ceramic membranes,showing prospective application prospects in the era of thermal insulating materials.

关键词： Silicon nitride nanowires Thermal insulation Fire-resistance High-temperature resistance

Outage-driven link selection for secure buffer-aided networks

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Science China(Information Sciences) 2022年第8期65卷 197-212页

作者： Dawei WANG Tianmi HE Fuhui ZHOU Julian CHENG ruonan zhang Qihui WU School of Electronics and Information Northwestern Polytechnical University College of Electronic and Information Engineering Nanjing University of Aeronautics and Astronautics National Mobile Communications Research Laboratory Southeast University School of Engineering The University of British Columbia Research & Development Institute of Northwestern Polytechnical University in Shenzhen Key Laboratory of Dynamic Cognitive System of Electromagnetic Spectrum Space Nanjing University of Aeronautics and Astronautics

In this paper, we investigate secure communication in a two-hop wireless network, where multiple buffer-aided relays assist to securely forward data from the sender to the destination threatened by a passive eavesdropper. To satisfy the security and delay requirements, we propose a novel link selection policy without the instantaneous wiretap channel state information. Different from the most current link selection policies,the proposed link selection policy is designed by joint considering the link secrecy outage probability and the buffer states. To evaluate the secrecy performance, we first characterize the system state transition matrix and the stationary state probability, and then derive the closed-form expressions for the secrecy outage probability and the secrecy rate. Moreover, we formulate a framework based on the queuing theory to analyze the end-to-end information delay at the source, the relays, and the queues, and derive the closed-form expression for the information delay. Finally, we conduct simulations to validate our theoretical performance analysis, and verify the performance improvement of the proposed outage-driven secure transmission scheme in terms of secrecy outage probability and information delay.

关键词： buffer-aided relay information delay link selection secrecy outage probability

Garlic Root Biomass as Novel Biosorbents for Malachite Green Removal： Parameter Optimization, Process Kinetics and Toxicity Test

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Chemical Research in Chinese Universities 2016年第4期32卷 647-654页

作者： REN Hejun zhang ruonan WANG Qiaochu PAN Hongyu WANG Yan Key Laboratory of Groundwater Resources and Environment Ministry of Education College of Environment and Resources Jilin University Changchun 130021 P. R. China College of Plant Sciences Jilin University Changchun 130062 P. R. China

The potential of the agricultural waste garlic root to remove malachite green（MG） from aqueous solutions was evaluated. The adsorption of this dye onto garlic root was confirmed by means of Fourier transform infrared analysis（FTIR） and scanning electron microscopy（SEM）. The equilibrium data fitted well into the Langmuir model（R2〉0.99）, and the adsorption kinetics followed the pseudo-second-order equation（R2〉0.99）. The maximum ad- sorption capacities of MG onto the adsorbent were 172.41 and 232.56 mg/g with the addition of 1 and 2 g/L garlic root, respectively. The optimal conditions for MG removal were established on the basis of orthogonal experiments（OAl6 matrix）. The concentrations of both MG and garlic root significantly affected the removal efficiency. The acute toxicity test indicated that the treated MG solutions were less toxic than the parent solutions. These results suggest that garlic root is a potential low-cost adsorbent for removing dye from industrial wastewater.

关键词： Garlic root Malachite green Adsorption Toxicity test Wastewater

Simultaneously enhancing mechanical and tribological properties of carbon fiber composites by grafting SiC hexagonal nanopyramids for brake disk application

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Journal of Materials Science & Technology 2022年第26期121卷 1-8页

作者： Yao Guo Leilei zhang Qiang Song ruonan zhang Fei Zhao Wei Li Hongchao Sheng Xianghui Hou Hejun Li State Key Laboratory of Solidification Processing Shaanxi Key Laboratory of Fiber Reinforced Light Composite MaterialsNorthwestern Polytechnical UniversityXi’an 710072China Department of Materials Science and Engineering Jiangsu University of Science and TechnologyZhenjiang 212003China Faculty of Engineering The University of NottinghamUniversity ParkNottingham NG72RDUnited Kingdom

Extensive attention has been drawn to the development of carbon fiber composites for their application in brake disks due to the increasing demand for brake disks with high mechanical strength and better tribological ***,we design SiC hexagonal nanopyramids modified carbon/carbon(SiCNPsC/C)composites,in which SiCNPs are radially grafted on the carbon fibers by the combined sol-gel and carbothermal reduction method,and pyrolytic carbon(Py C)matrix is deposited on nucleation sites including carbon fibers and SiCNPs by isothermal chemical vapor infiltration(ICVI).Benefiting from the special structure,SiCNPs-C/C composites exhibit superior mechanical and frictional *** with C/C composites,SiCNPs-C/C composites have 147%,90.3%,70.6%,and 117.9%improvement in the hardness,interlaminar shear strength,and out-of-plane and in-plane compressive strength,respectively,which is attributed to the optimized fiber/matrix(F/M)interfaces bonding and the enhanced cohesion strength of Py C *** addition,the friction coefficient of SiCNPs-C/C composites increases by 25.5%,and the wear rate decreases by 38.0%.This work provides an optional design thought for the nanomaterials and enlightens the mechanical and frictional modification of composites in the field of the brakes.

关键词： SiC hexagonal nanopyramids Carbon/carbon composites Microstructure Mechanical properties Tribological properties

Genome-wide identification and characterization of basic helix-loop-helix transcription factors in Spodoptera litura upon pathogen infection

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Insect Science 2022年第4期29卷 977-992页

作者： Jie zhang Mengyao Zhu Qilin Li Ting Tang Liang Wen Jielai Zhong ruonan zhang Xiao-Qiang Yu Yuzhen Lu Guangdong Provincial Key Laboratory of Insect Developmental Biology and Applied Technology Institute of Insect Science and TechnologySchool of Life SciencesSouth China Normal UniversityGuangzhouChina Guangzhou Key Laboratory of Insect Development Regulation and Application Research Institute of Insect Science and TechnologySchool of Life SciencesSouth China Normal UniversityGuangzhouChina

Basic helix-loop-helix(bHLH)transcription factors play an important role in a wide range of metabolic and developmental processes in eukaryotes,and bHLH proteins also participate in immune responses,especially in ***,their roles in insects upon entomopathogen infection are *** this study,54 bHLH genes in 41 families were identified in a polyphagous pest,Spodoptera litura,including a new bHLH gene in group B,which is specifically present in Lepidoptera and was thus named *** conserved amino acids in the bHLH domain,structural architecture,and chromosomal distribution of bHLH genes in *** were *** bHLH genes in Plutella xylostella and Apis mellifera were also updated,and genome-wide comparison and phylogenetic analysis of bHLH members in 5 holometabolous insects were *** expression profiles of *** bHLH(SlbHLH)genes in 3 tissues at different developmental stages and their responses to *** nucleopolyhedrovirus(SpltNPV),Nomuraea rileyi(Nr),and Bacillus thuringiensis(Bt)infection were *** SlbHLHs in group B were expressed and differentially expressed during pathogen infections,and SlbHLHs tended to be downregulated in the midgut of *** larvae after *** *** study provides an overview of bHLH family members in *** and their responses to different pathogens used for pest *** findings on bHLH members may contribute to uncovering the mechanism of host-pathogen interaction.

关键词： basic helix-loop-helix entomopathogen infection pest biocontrol Spodoptera liura