检索结果-南通市图书馆

Different Types of Bone Fractures Observed by Terahertz Time-Domain Spectroscopy

在线全文

学校读者我要写书评

暂无评论

Acta Mechanica Solida Sinica 2024年第3期37卷 468-477页

作者： Minghao Zhang Xianjia Meng Zhiyong Wang Chuanyong Qu Chuan Qu Donghui Fu Department of Mechanics Tianjin UniversityTianjin300072China tianjin key laboratory of Modern engineering Mechanics Tianjin300072China

Microcracks are common in compact bone,but their continued propagation can lead to macroscopic *** microcracks cannot be visualized radiographically,necessitating alternative noninvasive methods to identify excessive microcracking and prevent *** this study,terahertz time-domain spectroscopy(THz-TDS)was used to examine bone interiors near cracks resulting from loading in bovine tibia *** loading configurations,such as impact,quasi-static loading,and fatigue loading,known to induce different types of micro-scale damage,were *** values of refractive index and absorption coefficient of the bone samples were then determined from the THz-TDS spectra acquired before loading and after *** study revealed that different loading configurations led to varying terahertz optical coefficients associated with various types of bone ***,the refractive index notably increased under fatigue loading but remained relatively stable during quasi-static *** absorption coefficient of bone decreased only under fatigue ***,samples were subjected to axial and radial impacts without sustaining *** indicated that in the undamaged state,the change in refractive index was smaller compared to after impact failure,while the change in absorption coefficient remained consistent after *** radial impact loading,changes in refractive index and absorption coefficient were significantly more pronounced than under axial *** to loading,the measured value of refractive index was 2.72±0.11,and the absorption coefficient was 6.33±0.09 mm^(−1)at 0.5 THz.

关键词： Terahertz time-domain spectroscopy Bone Microdamage Noninvasive method

3D printedβ-sheet-reinforced natural polymer hydrogel bilayer tissue engineering scaffold

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Science China(Technological Sciences) 2024年第4期67卷 1170-1184页

作者： ZHAO XinRui NIE XiongFeng ZHANG XiaoPing SUN YaGe YANG Rong BIAN XinYu ZHANG Qian WANG HongYing XU ZiYang LIU WenGuang School of Materials Science and engineering Tianjin Key Laboratory of Composite and Functional MaterialsTianjin UniversityTianjin 300350China

It remains a significant challenge to fabricate natural polymer(NP)hydrogels with anti-swelling ability and high strengths in the physiological ***,theβ-sheet-reinforced NP hydrogel is developed by copolymerizing methacrylated gelatin(GelMA)and methacrylated silk fibroin(SFMA)in aqueous solution,followed by ethanol treatment(named GelMA-SFMAAL).Theβ-sheets formed by SFMA can act as a stable physical crosslink to enhance the mechanical properties and prolong the degradation of the GelMA ***,the chemical crosslinking in the GelMA-SFMA hydrogel prevents excessive aggregation of hydrophobicβ-sheets,thereby avoiding the formation of brittle *** obtained GelMA-SFMA-AL hydrogels exhibit considerably enhanced mechanical properties(Young's modulus:0.89–3.68 MPa;tensile strength:0.31–0.96 MPa;toughness:0.09–0.63 MJ/m^(3);compressive modulus:0.78–2.20 MPa;compressive strength:2.65–5.93 MPa)compared with GelMA-SFMA hydrogels(Young's modulus:0.04–0.13 MPa;tensile strength:0.04–0.07 MPa;toughness:0.01–0.02 MJ/m^(3);compressive modulus:0.03–0.09 MPa;compressive strength:0.30–0.64 MPa).A bilayer osteochondral scaffold is constructed via digital light processing(DLP)three-dimensiaonl(3D)printing technology,comprising GelMA-SFMA@diclofenac sodium(DS)-AL as the top layer and GelMA-SFMA@bioactive glass(BG)-AL as the bottom *** bilayer hydrogel scaffold is demonstrated to support cell attachment and spreading,and facilitate osteogenic differentiation of rat bone marrow stem cells in *** vivo implantation experiment suggests this bilayer scaffold is promising to be used for osteochondral tissue regeneration.

关键词： silk fibroin β-sheet high-strength hydrogel natural polymer osteochondral regeneration

Porous metal oxides in the role of electrochemical CO_(2) reduction reaction

在线全文

学校读者我要写书评

暂无评论

Journal of Energy Chemistry 2024年第1期88卷 373-398,I0009页

作者： Ziqi Zhang Jinyun Xu Yu Zhang Liping Zhao Ming Li Guoqiang Zhong Di Zhao Minjing Li Xudong Hu Wenju Zhu Chunming Zheng Xiaohong Sun School of Chemical engineering and Technology Tianjin Key Laboratory of Green Chemical Technology and Process EngineeringState Key Laboratory of Separation Membrane and Membrane ProcessesTiangong UniversityTianjin 300387China School of Materials Science and engineering Key Laboratory of Advanced Ceramics and Machining TechnologyMinistry of EducationTianjin UniversityTianjin 300072China

The global energy-related CO_(2) emissions have rapidly increased as the world economy heavily relied on fossil *** paper explores the pressing challenge of CO_(2) emissions and highlights the role of porous metal oxide materials in the electrocatalytic reduction of CO_(2)(CO_(2)RR).The focus is on the development of robust and selective catalysts,particularly metal and metal-oxide-based *** metal oxides offer high surface area,enhancing the accessibility to active sites and improving reaction *** tunability of these materials allows for tailored catalytic behavior,targeting optimized reaction mechanisms for CO_(2)*** work also discusses the various synthesis strategies and identifies key structural and compositional features,addressing challenges like high overpotential,poor selectivity,and low *** on these insights,we suggest avenues for future research on porous metal oxide materials for electrochemical CO_(2) reduction.

关键词： CO_(2)reduction Carbon dioxide Transformation Porous metal oxides Electrocatalysis

Donor-acceptor covalent organic frameworks-confined ultrafine bimetallic Pt-based nanoclusters for enhanced photocatalytic H_(2)generation

在线全文

学校读者我要写书评

暂无评论

Nano Research 2024年第7期17卷 5835-5844页

作者： Yu Liu Yawen Shi Hua Wang Shengbo Zhang Collaborative Innovation Center of Chemical Science and engineering(tianjin) Key Laboratory for Green Chemical Technology of the Ministry of EducationSchool of Chemical Engineering and TechnologyTianjin UniversityTianjin 300350China School of Environmental Science and engineering Tianjin Key Laboratory of Biomass/Wastes UtilizationTianjin UniversityTianjin 300350China

Photocatalytic hydrogen generation from hydrogen storage media is an effective and promising approach for the green hydrogen industry as well as for achieving carbon neutrality ***,the lower photocatalytic efficiency due to the limited light trapping capacity,low electron transfer rate,and severe aggregation of nanoparticles caused by high surface energy seriously restricts their practical ***,we constructed a series of donor–acceptor(D–A)type covalent organic frameworks to confine ultrafine bimetallic Pt-based nanoclusters for photocatalytic hydrogen generation from ammonia borane(AB)*** visible light irradiation at 20℃,PtCo_(2)@covalent organic framework(COF)showed the highest photocatalytic activity with a turnover frequency(TOF)of 486 min−*** and density functional theory(DFT)calculations reveal that the high catalytic activity is mainly attributed to the strong electronic interactions between D–A type COF and ultrafine PtCo_(2)***,the D–A type COF can significantly enhance the light-trapping ability by fine-tuning the electron-acceptor type in the framework,and accelerate the photogenerated electron transfer from D–A type COF to PtCo_(2)nanocluster,which promotes the adsorption and activation of H_(2)O and AB molecules and accelerates hydrogen ***,PtCo_(2)@COF also exhibited ultra-high durability due to the significantly enhanced resistance to nanocluster aggregation caused by the nanopore confinement effect of D–A type *** believe that this work will provide a theoretical guide for the rational design of efficient D–A COFbased catalysts for photocatalysis.

关键词： light trapping electron transfer donor-acceptor covalent organic frameworks(D-A COFs) bimetallic nanoclusters photocatalysis

Trojan horses in tumor:engineered pyroelectric and photodynamic nanocomposites for NIR-induced cell apoptosis and tumor growth inhibition

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Science China Chemistry 2024年第9期67卷 3050-3062页

作者： Yanxi Yang Xinru Kong Xueli Ren Yandai Lin Zhe Liu Academy of Medical engineering and Translational Medicine Tianjin UniversityTianjin 300072China tianjin key laboratory of Brain Science and Neural engineering Tianjin UniversityTianjin 300072China

It is desirable but always challenging to develop a cutting-edge tumor treatment strategy with high therapeutic efficacy,lesiontargeted precision and mild *** to traditional treatment modalities,photodynamic therapy has been widely studied since the generation of reactive oxygen species(ROS)at cancerous lesions unprecedentedly offers a convenient approach for localized tumor ***,the consumption of oxygen for ROS production in a hypoxic tumor microenvironment has dramatically limited its feasibility and ***,the engineered nanocomposites of BTO@PDA-ICGHA with photodynamic and pyroelectric performances have been fabricated and applied to the photodynamic-pyroelectric dynamic *** continuing ROS production derived from intracellular oxygen(O_(2))and water(H_(2)O)by laser irradiation contributed to the superb tumor cell apoptosis and significant tumor growth ***,this study has validated a new concept by depositing the engineered nanocomposites at the tumor just like Trojan horses,facilitating ROS release as killers and exerting the NIR-induced cell apoptosis and tumor growth inhibition with high therapeutic efficiency and expectable translational perspectives.

关键词： nanocomposites pyroelectric effect photodynamic therapy cell apoptosis tumor growth inhibition

同方期刊数据库

Carbon-based materials with combined functions of thermal management and electromagnetic protection: Preparation, mechanisms, properties, and applications

在线全文

学校读者我要写书评

暂无评论

Nano Research 2024年第3期17卷 883-903页

作者： Junwei Yue Yiyu Feng Mengmeng Qin Wei Feng School of Materials Science and engineering and tianjin key laboratory of Composite and Functional Materials Tianjin UniversityTianjin 300350China

The proliferation of high-power,highly informationized,and highly integrated electronic devices and weapons equipment has given rise to increasingly conspicuous issues about electromagnetic(EM)pollution and thermal *** issues,in turn,impose constraints on the performance of such equipment and jeopardize personnel *** materials,owing to their diverse and modifiable structures,offer adjustable thermal and electric conductivity,rendering them highly promising for applications in fields such as thermal management and EM protection which have garnered extensive research and *** pursuit of integrated device and equipment development has elevated the demand for multifunctional materials,prompting significant research into carbon-based composite materials that include both thermal management and EM protection ***,there are no relevant reviews on this topic at ***,this work consolidates research findings from recent years on carbon matrix composites exhibiting dual attributes of thermal management and EM *** attributes include thermally conductive electromagnetic interference(EMI)shielding materials,thermally insulating EMI shielding materials,thermally conductive EM wave(EMW)absorbing materials,and thermally insulating EMW absorbing *** paper elucidates the fundamental principles underpinning thermal conduction,thermal insulation,EMW absorbing,and EMI ***,it engages in discussions surrounding areas of contention,design strategies,and the functional properties of various material ***,the paper concludes by presenting the challenges encountered and potential research strategies about composites endowed with both thermal management and EM protection functionalities,while also envisaging the development of novel multifunctional EM protection materials.

关键词： carbon-based composites electromagnetic interference shielding microwave absorption thermal conduction thermal insulation

D-band center coordination modulated enzyme-like activity in Fe-Cu dual-metal single-atom nanozymes

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Nano Research 2024年第7期17卷 5872-5883页

作者： Ling Liu Shaofang Zhang Guo Li Yadong Zhe Jiamin Liu Xinxu Zhang Jiahao Wei Xin Sun Yonghui Li Xiao-Dong Zhang tianjin key laboratory of Brain Science and Neural engineering Academy of Medical Engineering and Translational MedicineTianjin UniversityTianjin 300072China Department of Physics and tianjin key laboratory of Low Dimensional Materials Physics and Preparing Technology School of SciencesTianjin UniversityTianjin 300350China

After explorations in a diversity of single-atom nanozymes(SAzymes),developing dual-centered SAzymes becomes a promising approach for superior catalytic *** confusing mechanisms including atomic coordination,spatial configuration,and metal–metal atom interaction hinder the development and design of ***,a dual-centered Fe-Cu-N_(x)SAzyme exhibits excellent peroxidase(POD)-and catalase(CAT)-like activities with d-band center(ε_(d))coordination of Fe and Cu in multiple reaction stages,which plays a critical role in the adsorption of H_(2)O_(2)molecule and H_(2)O and O_(2)***,the dband center coordination,which can be represented byε_(d)(Fe)–ε_(d)(Cu)shifts,leads to the competition between one-side and bilateral adsorption,which determines the favorable reaction path with lower energy *** on experimental statistics,simulated formation energies,and reaction barriers,3 configurations,Fe-Cu-N6-I,Fe-Cu-N_(8)-II,and Fe-Cu-N_(8)-III,are modeled and ***,configuration-dependent catalytic selectivity and the competition between one-side and bilateral adsorption can be unveiled by d-band center coordination paradigm *** simulations suggest that the unsymmetrical charge distribution over the three Fe-Cu configurations could tune the adsorption strength compared with the counterparts FeN_(4)and CuN_(4).The present work provides a potential route for optimizing enzyme-like catalysis by designing the dual-or even triple-metal SAzymes,which demonstrates the large space to modulate the metal atomic configuration and interaction.

关键词： single-atom catalysis Fe-Cu dual-metal d-band center coordination enzyme mimicking competitive adsorption mechanisms

Optimization of biofuel supply chain integrated with petroleum refineries under carbon trade policy

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Frontiers of Chemical Science and engineering 2024年第3期18卷 113-122页

作者： Wenhui Zhang Yiqing Luo Xigang Yuan Chemical engineering Research Center School of Chemical Engineering and TechnologyTianjin UniversityTianjin300350China State key laboratory of Chemical engineering Tianjin UniversityTianjin300350China

The use of fossil fuels results in significant carbon dioxide *** have been increasingly adopted as sustainable alternatives to fossil fuel to address this environmental *** petroleum refineries into biofuel supply chains is an effective approach to mitigating greenhouse gas emissions and improving environmental *** this study,an integrated supply chain optimization framework was established,considering the carbon trade *** addition,a mixed-integer nonlinear programming model was developed to optimize the selection of biomass suppliers,construction of pretreatment plants and biorefineries,integration of petroleum refineries,and selection of transportation routes with the objective of minimizing the total annual *** example is presented to illustrate the applicability of the *** optimization results show that integrating petroleum refineries into biofuel supply chains effectively mitigates carbon *** trade policies can have a direct impact on the total annual cost and carbon emissions of the supply chain.

关键词： renewable energy biofuel supply chain carbon trade policy

Experimental Study on Towing Characteristics of Composite Bucket Wellhead Platform

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

China Ocean engineering 2024年第3期38卷 531-542页

作者： ZHANG Pu-yang LIU Ying-fei LE Cong-huan DING Hong-yan BAI Yu State key laboratory of Hydraulic engineering Intelligent Construction and Operation Tianjin UniversityTianjin 300072China

With the rapid development of large-scale development of marginal oilfields in China,simple wellhead platforms that are simple in structure and easy to install have become an inevitable choice in the process of oilfield ***,traditional simple wellhead platforms are often discarded after a single *** pursuit of a more costeffective approach to developing marginal oilfields,this paper proposes a new offshore oil field development facility—an integrated bucket foundation for wellhead *** verify the safety of its towing behavior and obtain the dynamic response characteristics of the structure,this paper takes a bucket integrated bucket foundation for wellhead platform with a diameter of 40 m as the research *** combining physical model tests and numerical simulations,it analyzes the static stability and dynamic response characteristics of the structure during towing,complete with the effects of the draft,wave height,wave period,and towing point height,which produce the dynamic responses of the structure under different influence factors,such as roll angle,pitch angle,heave acceleration and towing force as well as the sensibility to transport *** results show that the integrated bucket foundation for wellhead platform is capable of self-floating towing,and its movement is affected by the local environment,which will provide a reference for actual projects.

关键词： composite bucket foundation wellhead platform air flotation towing model test