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Practical optimization of deployable and scissor-like structures using a fast GA method

M. SALAR, M. R. GHASEMI, B. DIZANGIAN

《结构与土木工程前沿(英文)》 2019年 第13卷 第3期   页码 557-568 doi: 10.1007/s11709-018-0497-z

摘要: This paper addresses practical sizing optimization of deployable and scissor-like structures from a new point of view. These structures have been recently highly regarded for beauty, lightweight, determine behavior, proper performance against lateral loads and the ability of been compactly packaged. At this time, there is a few studies done considering practical optimization of these structures. Loading considered here includes wind and gravity loads. In foldable scissor-like structures, connections have a complex behavior. For this reason, in this study, the authors used the ABAQUS commercial package as an analyzer in the optimization procedure. This made the obtained optimal solutions highly reliable from the point of view of applicability and construction requirements. Also, to do optimization task, a fast genetic algorithm method, which has been recently introduced by authors, was utilized. Optimization results show that despite less weight for aluminum models than steel models, aluminum deployable structures are not affordable because they need more material than steel structures and cause more environmental damage.

关键词: optimization     scissor-like structures     deployable structures     genetic algorithm     ABAQUS    

Damage detection in beam-like structures using static shear energy redistribution

《结构与土木工程前沿(英文)》 2022年 第16卷 第12期   页码 1552-1564 doi: 10.1007/s11709-022-0903-4

摘要: In this study, a static shear energy algorithm is presented for the damage assessment of beam-like structures. According to the energy release principle, the strain energy of a damaged element suddenly changes when structural damage occurs. Therefore, the change in the static shear energy is employed to determine the damage locations in beam-like structures. The static shear energy is derived from the spectral factorization of the elementary stiffness matrix and structural deflection variation. The advantage of using shear energy as opposed to total energy is that only a few deflection data points of the beam structure are required during the process of damage identification. Another advantage of the proposed approach is that damage detection can be performed without establishing a structural finite-element model in advance. The proposed technique is first validated using a numerical example with single, multiple, and adjacent damage scenarios. A channel steel beam and rectangular concrete beam are employed as experimental cases to further verify the proposed approach. The results of the simulation and experiment examples indicate that the proposed algorithm provides a simple and effective method for defect localization in beam-like structures.

关键词: damage detection     beam structure     strain energy     static displacement variation     energy damage index    

Enhanced Fenton-like process over Cu/L(+)-ascorbic acid co-doping mesoporous silica for toxicity reduction

《环境科学与工程前沿(英文)》 2023年 第18卷 第4期 doi: 10.1007/s11783-024-1804-7

摘要:

● Cu-C-MSNs are developed via a co-doping step of Cu with L(+)-ascorbic acid.

关键词: Cation-π structures     Polarization electric field     Fenton-like process     Contaminants cleavage    

Salt-assisted synthesis of tree-like oriented SnO

Jinquan SUN, Zifeng YAN, Hongzhi CUI

《化学科学与工程前沿(英文)》 2011年 第5卷 第2期   页码 227-230 doi: 10.1007/s11705-010-0566-x

摘要: Tree-like SnO nanodendrites in large amounts have been prepared through two-step reactions. The nanoparticles used as the precursors have taken aggregation forming tree-like or string of nanodendrtie. The samples were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM) and energy dispersive spectrometer (EDS), respectively. The results showed that molar ratio of the ethanol/distilled water is an important factor for formation of the different dendrite structures. There are different morphologies between tree-like SnO nanowhiskers and bunch of SnO nanorods. However, they are growing along the .

关键词: crystal morphology     nano-structures     nanodendrite    

Synthesis of iron(II) complexes with asymmetric N

Wolfgang Bauer, Tanja Ossiander, Birgit Weber

《化学科学与工程前沿(英文)》 2018年 第12卷 第3期   页码 400-408 doi: 10.1007/s11705-018-1753-4

摘要:

The synthesis of new Schiff base-like ligands with asymmetric substituents pattern and their iron complexes with pyridine as axial ligand is described. Two of the ligands and one of the iron(II) complexes were characterized by single crystal X-ray structure analysis. One of the the iron(II) complexes shows spin crossover behavior while the others remain in the high spin state. The influence of the reduced symmetry of the ligand on the properties of the complexes is discussed.

关键词: iron     Schiff base-like ligands     magnetism     spin crossover     X-ray structures    

Distinct immune escape and microenvironment between RG-like and pri-OPC-like glioma revealed by single-cell

《医学前沿(英文)》 doi: 10.1007/s11684-023-1017-7

摘要: The association of neurogenesis and gliogenesis with glioma remains unclear. By conducting single-cell RNA-seq analyses on 26 gliomas, we reported their classification into primitive oligodendrocyte precursor cell (pri-OPC)-like and radial glia (RG)-like tumors and validated it in a public cohort and TCGA glioma. The RG-like tumors exhibited wild-type isocitrate dehydrogenase and tended to carry EGFR mutations, and the pri-OPC-like ones were prone to carrying TP53 mutations. Tumor subclones only in pri-OPC-like tumors showed substantially down-regulated MHC-I genes, suggesting their distinct immune evasion programs. Furthermore, the two subgroups appeared to extensively modulate glioma-infiltrating lymphocytes in distinct manners. Some specific genes not expressed in normal immune cells were found in glioma-infiltrating lymphocytes. For example, glial/glioma stem cell markers OLIG1/PTPRZ1 and B cell-specific receptors IGLC2/IGKC were expressed in pri-OPC-like and RG-like glioma-infiltrating lymphocytes, respectively. Their expression was positively correlated with those of immune checkpoint genes (e.g., LGALS3) and poor survivals as validated by the increased expression of LGALS3 upon IGKC overexpression in Jurkat cells. This finding indicated a potential inhibitory role in tumor-infiltrating lymphocytes and could provide a new way of cancer immune evasion.

关键词: single-cell RNA-seq     glioma     radial glia     primitive oligodendrocyte precursor cell     immune escape    

Self-sacrificial templating synthesis of flower-like nickel phyllosilicates and its application as high-performance

《化学科学与工程前沿(英文)》 2022年 第16卷 第4期   页码 484-497 doi: 10.1007/s11705-021-2074-6

摘要: The nanocomposites of flower-like nickel phyllosilicate particles incorporated into epoxy resin were fabricated via an in-situ mixing process. The flower-like nickel phyllosilicate particles were firstly synthesized using a mild self-sacrificial templating method, and the morphology and lamellar structure were examined carefully. Several properties of mechanical, thermal and tribological responses of epoxy nanocomposites were performed. It was demonstrated that adequate flower-like nickel phyllosilicate particles dispersed well in the matrix, and the nanocomposites displayed enhanced tensile strength and elastic modulus but decreased elongation at break as expected. In addition, friction coefficient and wear rate were increased first and then decreased along with the particle content, and showed the lowest values at a mass fraction of 5%. Nevertheless, the incorporated flower-like nickel phyllosilicate particles resulted in the continuously increasing thermal stability of epoxy resin (EP) nanocomposites. This study revealed the giant potential of flower-like particles in preparing high-quality EP nanocomposites.

关键词: nickel phyllosilicate     flow-like structure     mechanical property     thermal stability     tribological performance    

Toll-like receptors in innate immunity and infectious diseases

Min-Hao WU, Ping ZHANG, Xi HUANG,

《医学前沿(英文)》 2010年 第4卷 第4期   页码 385-393 doi: 10.1007/s11684-010-0600-x

摘要: The protective ability of host defense system is largely dependent on germ-line encoded pattern-recognition receptors (PRRs). These PRRs respond to a variety of exogenous pathogens or endogenous danger signals, by recognizing some highly conserved structures such as pathogen-associated molecular patterns (PAMPs) and danger/damage associated molecular patterns (DAMPs). The most studied PRRs are Toll-like receptors (TLRs). Activation of TLRs triggers production of inflammatory cytokines and type I interferons (IFNs) via myeloid differentiation primary response gene 88 (MyD88)-dependent or-independent signaling respectively, thereby modulating innate and adaptive immunity, as well as inflammatory responses. This review introduces the classification, structure, and specific ligands of TLRs, and focuses on their signal pathways and biological activities, as well as clinical relevance. These studies of TLRs in the innate immune system have implications for the prevention and treatment of a variety of infectious diseases, including tuberculosis (TB), microbial keratitis, and hepatitis B and C.

关键词: Toll-like receptors     innate immunity     infectious disease     inflammation    

Dispersion of “guava-like” silica/polyacrylate nanocomposite particles in polyacrylate matrix

QI Dongming, YANG Lei, WU Minghua, SHAO Jianzhong, BAO Yongzhong

《化学科学与工程前沿(英文)》 2008年 第2卷 第2期   页码 127-134 doi: 10.1007/s11705-008-0033-0

摘要: A series of “guava-like” silica/polyacrylate nanocomposite particles with close silica content and different grafting degrees were prepared via mini-emulsion polymerization using 3-(trimethoxysilyl)propyl methacrylate (TSPM) modified silica/acrylate dispersion. The silica/polyacrylate composite particles were melt-mixed with unfilled polyacrylate (PA) resin to prepare corresponding silica/polyacrylate molded composites and the dispersion mechanism of these silica particles from the “guava-like” composite particles into polyacrylate matrix was studied. It was calculated that about 110 silica particles were accumulated in the bulk of every silica/polyacrylate composite latex particle. Both the solubility tests of silica/polyacrylate composite latex particles in tetrahydrofuran (THF) and the section transmission electron microscope (TEM) micrographs of silica/polyacrylate molded composites indicated that the grafting degree of silica particles played a crucial role in the dispersion of silica/polyacrylate composite particles into the polyacrylate matrix. When the grafting degree of polyacrylate onto silica was in a moderate range (ca. 20%–70%), almost all of silica particles in these “guava-like” composite particles were dispersed into the polyacrylate matrix in a primary-particle-level. However, at a lower grafting degree, massive silica aggregations were found in molded composites because of the lack of steric protection. At a greater grafting degree (i.e., 200%), a cross-linked network was formed in the silica/polyacrylate composite particles, which prevented the dispersion of composite particles in THF and polyacrylate matrix as primary particles.

关键词: silica/polyacrylate composite     cross-linked network     –70     guava-like     TEM    

Layer-like FAU-type zeolites: A comparative view on different preparation routes

Bastian Reiprich, Tobias Weissenberger, Wilhelm Schwieger, Alexandra Inayat

《化学科学与工程前沿(英文)》 2020年 第14卷 第2期   页码 127-142 doi: 10.1007/s11705-019-1883-3

摘要: The creation of intergrown layer-like zeolite crystals is one route to form hierarchical zeolites. Faujasite-type (FAU-type) zeolites are among the industrially most important zeolites and the implementation of hierarchical porosity is a promising way to optimise their catalytic and adsorptive performance. After a short general survey into routes for the preparation of hierarchical pore systems in FAU, we will review the currently existing strategies for the synthesis of FAU with layer-like morphology. Those strategies are mainly based on the presence of morphology modifying agents in the synthesis mixture. However, a very recent approach is the synthesis of layer-like FAU-type zeolite crystals assembled in an intergrown manner in the absence of such additives, just by finely adjusting the crystallization temperature. This additive-free preparation route for layer-like FAU, which appears very attractive from an ecological as well as economic point of view, is highlighted in this review. Concluding, a comparison, including powder X-ray diffraction, scanning and transmission electron microscopy, nitrogen physisorption and elemental analysis, between conventional FAU and three layer-like FAU obtained by different synthesis routes was carried out to show the structural, morphological and textural differences and similarities of these materials.

关键词: FAU     hierarchical zeolite     layer-like morphology    

Synthesis and characterization of well-defined comb-like branched polymers

LI Aixiang, LU Zaijun, LÜ Zijian

《化学科学与工程前沿(英文)》 2008年 第2卷 第4期   页码 407-411 doi: 10.1007/s11705-008-0064-6

摘要: Well-defined comb-like branched polymers having one branch in each repeating unit have been successfully synthesized by the coupling reaction of living polystyrene (PS) and polyisoprene (PI) anions with 1, 1-diphenylethenyl (DPE) groups along PS backbone prepared via atom transfer radical polymerization (ATRP) of 4-vinylbenzyloxy benzophenone (Sc) followed by Wittig reaction. The resulting comb-like branched polymers were characterized by IR, H-NMR, gel permeation chromatography (GPC) and static light scattering (SLS) in detail. The effect of living chains and DPE group molar ratio on grafting efficiency was discussed. The results show the coupling reaction of living chains and DPE groups was highly effective, and the coupling efficiency can be controlled via the feed molar ratios of living chains and DPE groups. Moreover, the effect of molecular weights of backbone (PSe) and PSLi or PILi on grafting efficiency was also discussed. The results show that when excess living polymers were used, the almost quantitative grafting efficiency could be achieved.

关键词: grafting efficiency     polyisoprene     quantitative grafting     effective     molecular    

Novel synthetic approaches and TWC catalytic performance of flower-like Pt/CeO

Zongcheng ZHAN,Xiaojun LIU,Dongzhu MA,Liyun SONG,Jinzhou LI,Hong HE,Hongxing DAI

《环境科学与工程前沿(英文)》 2014年 第8卷 第4期   页码 483-495 doi: 10.1007/s11783-013-0595-z

摘要: A novel Ultrasonic Assisted Membrane Reduction (UAMR)-hydrothermal method was used to prepare flower-like Pt/CeO catalysts. The texture, physical/chemical properties, and reducibility of the flower-like Pt/CeO catalysts were characterized by X-Ray Diffraction (XRD), Scanning Electron Microscope (SEM), Transmission Electron Microscope (TEM), N adsorption, and hydrogen temperature programmed reduction (H -TPR) techniques. The catalytic performance of the catalysts for treating automobile emission was studied relative to samples prepared by the conventional wetness impregnation method. The Pt/CeO catalysts fabricated by this novel method showed high specific surface area and metal dispersion, excellent three-way catalytic activity, and good thermal stability. The strong interaction between the Pt nanoparticles and CeO improved the thermal stability. The Ce ions were incorporated into the surfactant chains and the Pt nanoparticles were stabilized through an exchange reaction of the surface hydroxyl groups. The SEM results demonstrated that the Pt/CeO catalysts had a typical three-dimensional (3D) hierarchical porous structure, which was favorable for surface reaction and enhanced the exposure degree of the Pt nanoparticles. In brief, the flower-like Pt/CeO catalysts prepared by UAMR-hydrothermal method exhibited a higher Pt metal dispersion, smaller particle size, better three-way catalytic activity, and improved thermal stability versus conventional materials.

关键词: three-way catalyst     flower-like     Ultrasonic Assisted Membrane Reduction (UAMR)     Pt nanoparticles    

Application and development of modern long-span space structures in China

Shilin DONG, Yang ZHAO, Dong XING

《结构与土木工程前沿(英文)》 2012年 第6卷 第3期   页码 224-239 doi: 10.1007/s11709-012-0166-6

摘要: Modern long-span space structures, developed during the 1970s and 1980s, are light and effective structures based on new technologies and light-weight high-strength materials, such as membranes and steel cables. These structures include air-supported membrane structures, cable-membrane structures, cable truss structures, beam string structures, suspen-domes, cable domes, composite structures of cable dome and single-layer lattice shell, Tensairity structures and so forth. For the premodern space structures widely used since the mid-twentieth century (such as thin shells, space trusses, lattice shells and ordinary cable structures), new space structures have been developed by the combination of different structural forms and materials. The application of prestressing technology and the innovation of structural concepts and configurations are also associated with modern space structures, including composite space trusses, open-web grid structures, polyhedron space frame structures, partial double-layer lattice shells, cable-stayed grid structures, tree-type structures, prestressed segmental steel structures and so forth. This paper provides a review of the structural characteristics and practical applications in China of modern rigid space structures, modern flexible space structures and modern rigid-flexible combined space structures.

关键词: modern long-span space structures     rigid space structures     flexible space structures     rigid-flexible combined space structures     application and development    

Degradation of antipyrine in the Fenton-like process with a La-doped heterogeneous catalyst

Shicheng Wei, Cuiping Zeng, Yaobin Lu, Guangli Liu, Haiping Luo, Renduo Zhang

《环境科学与工程前沿(英文)》 2019年 第13卷 第5期 doi: 10.1007/s11783-019-1149-9

摘要: Abstract A La-doped Co-Cu-Fe catalyst was synthesized for the antipyrine (ANT) removal. The La-doped catalyst had higher ANT removal than the control (95% vs. 54%). La reduced the particle size and increased the specific surface area of catalyst. The aim of this study was to synthesize a novel lanthanum (La) doped catalyst and to investigate antipyrine removal in wastewater using the Fenton-like process with the catalyst. The La-doped Co-Cu-Fe catalyst was synthesized using the modified hydrothermal method. Results showed that the La-doped catalyst had higher specific surface area and lower particle size than the catalyst without La doping (i.e., the control) (267 vs. 163 m2/g and 14 vs. 32 nm, respectively). Under the conditions of catalyst dosage 0.5 g/L, H2O2 concentration 1.70 g/L, and NaHCO3 0.1 g/L, the antipyrine removal within 60 min using the Fenton-like process with the La-doped catalyst was much higher than that with the control (95% vs. 54%). The hydroxyl radical concentration with the La-doped catalyst within 60 min was two times higher than that with the control (49.2 vs. 22.1 mg/L). The high catalytic activity of La-doped catalyst was mainly attributed to its high specific surface area based on the X-ray photoelectron spectroscopy result. Our La-doped catalyst should have great potential to remove antipyrine in wastewater using the heterogeneous Fenton-like process.

关键词: Antipyrine     Lanthanum     Catalyst     Fenton-like process    

Tribological properties of onion like fullerenes and NiFe

Ruixiang WANG,Yihao ZHANG,Haizhou WU

《能源前沿(英文)》 2021年 第15卷 第1期   页码 208-212 doi: 10.1007/s11708-017-0454-x

摘要: A novel way for a compressor to improve its coefficient of performance and enhance its reliability by employing nano-refrigeration lubricant oil was proposed. Onion like fullerenes (OLFs) and NiFe O nano-composites, modified by Span 80, were dispersed in refrigeration oil KFR22 by solid grinding (SG). Morphologies of NiFe O nano-composites were characterized by using transmission electron microscope (TEM). The tribological properties as a refrigeration lubricants additive were investigated using SRV (II), a multi-functional reciprocating friction and wear tester. The results showed that the friction coefficient was decreased from 0.15 to 0.04.

关键词: refrigeration lubricants     friction coefficient     nano-composites     reciprocating motion     onion like fullerenes    

标题 作者 时间 类型 操作

Practical optimization of deployable and scissor-like structures using a fast GA method

M. SALAR, M. R. GHASEMI, B. DIZANGIAN

期刊论文

Damage detection in beam-like structures using static shear energy redistribution

期刊论文

Enhanced Fenton-like process over Cu/L(+)-ascorbic acid co-doping mesoporous silica for toxicity reduction

期刊论文

Salt-assisted synthesis of tree-like oriented SnO

Jinquan SUN, Zifeng YAN, Hongzhi CUI

期刊论文

Synthesis of iron(II) complexes with asymmetric N

Wolfgang Bauer, Tanja Ossiander, Birgit Weber

期刊论文

Distinct immune escape and microenvironment between RG-like and pri-OPC-like glioma revealed by single-cell

期刊论文

Self-sacrificial templating synthesis of flower-like nickel phyllosilicates and its application as high-performance

期刊论文

Toll-like receptors in innate immunity and infectious diseases

Min-Hao WU, Ping ZHANG, Xi HUANG,

期刊论文

Dispersion of “guava-like” silica/polyacrylate nanocomposite particles in polyacrylate matrix

QI Dongming, YANG Lei, WU Minghua, SHAO Jianzhong, BAO Yongzhong

期刊论文

Layer-like FAU-type zeolites: A comparative view on different preparation routes

Bastian Reiprich, Tobias Weissenberger, Wilhelm Schwieger, Alexandra Inayat

期刊论文

Synthesis and characterization of well-defined comb-like branched polymers

LI Aixiang, LU Zaijun, LÜ Zijian

期刊论文

Novel synthetic approaches and TWC catalytic performance of flower-like Pt/CeO

Zongcheng ZHAN,Xiaojun LIU,Dongzhu MA,Liyun SONG,Jinzhou LI,Hong HE,Hongxing DAI

期刊论文

Application and development of modern long-span space structures in China

Shilin DONG, Yang ZHAO, Dong XING

期刊论文

Degradation of antipyrine in the Fenton-like process with a La-doped heterogeneous catalyst

Shicheng Wei, Cuiping Zeng, Yaobin Lu, Guangli Liu, Haiping Luo, Renduo Zhang

期刊论文

Tribological properties of onion like fullerenes and NiFe

Ruixiang WANG,Yihao ZHANG,Haizhou WU

期刊论文