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Solid-conversion synthesis of three-dimensionally ordered mesoporous ZSM-5 catalysts for the methanol-to-propylene reaction

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FRONTIERS OF CHEMICAL SCIENCE AND ENGINEERING 2024年第8期18卷 93-0页

作者： Chun, Weilong yang, chenbiao Wang, Xu yang, Xin Chen, Huiyong Northwest Univ Sch Chem Engn Xian 710069 Peoples R China Northwest Univ Int Sci & Technol Cooperat Base Clean Utilizat Hyd Collaborat Innovat Ctr Dev Energy & Chem Ind North Chem Engn Res CtrMinist Educ Adv Use Technol Shan Xian 710069 Peoples R China

A facile synthesis of hierarchical ZSM-5 with the three-dimensionally ordered mesoporosity (3DOm ZSM-5) was achieved by solid conversion (SC) of SiO2 colloidal crystals to high-crystalline ZSM-5. The products of 3DZ5_S/C and 3DZ5_S, which were severally transformed from the carbon-padded SiO2 colloidal crystals and the initial SiO2 colloidal crystals, exhibited not only a similar ordered structure and acidity but also higher crystallinity and more balanced meso-/micropore combination in comparison with 3DZ5_C obtained by the conventional confined space crystallization approach. All three synthesized 3DZ5 catalysts showed improved methanol-to-propylene performance than the commercially microporous ZSM-5 (CZ5), embodied in five times longer lifetime, higher propylene selectivity and Spropylene/Sethylene ratio (P/E), and superior coke toleration with lower formation rate of coke (Rcoke). Moreover, the 3DZ5_S catalyst in situ converted from SiO2 colloidal crystals presented the highest selectivities of propylene (42.51%) and light olefins (74.6%) among all three 3DZ5 catalysts. The high efficiency in synthesis and in situ utilization of SiO2 colloidal crystals demonstrate the proposed SC strategy to be more efficiently and eco-friendly for the high-yield production of not only 3DOm ZSM-5 but also other types of hierarchical zeolites.

关键词： hierarchical zeolite three-dimensionally ordered mesoporosity ZSM-5 solid conversion methanol-to-propylene HIERARCHICAL ZSM-5 IMPRINTED ZEOLITES DIRECTED SYNTHESIS EXTERNAL SURFACE PERFORMANCE NANOSHEETS GROWTH MFI DIFFUSION H-ZSM-5

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影响TPO防水卷材焊接剥离强度的因素探讨

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新型建筑材料 2024年第1期51卷 137-139,154页

作者：杨琛彪陈香志科顺防水科技股份有限公司广东顺德528300

在国内单层防水卷材屋面工程中,TPO防水卷材的应用日渐增多。在项目现场施工时,影响TPO卷材焊接剥离强度的因素较多,但最主要的因素还是人为因素,比如热风焊机调试的温度和速度、施工人员操作熟练度、TPO卷材被污染情况等等,当然现场环... 详细信息

在国内单层防水卷材屋面工程中,TPO防水卷材的应用日渐增多。在项目现场施工时,影响TPO卷材焊接剥离强度的因素较多,但最主要的因素还是人为因素,比如热风焊机调试的温度和速度、施工人员操作熟练度、TPO卷材被污染情况等等,当然现场环境情况也是影响焊接剥离强度因素之一。为保证卷材的接缝剥离强度,焊接时热风焊机需保持适宜的温度和速度;保持卷材表面干净、干燥、无污染;避免在恶劣天气下施工。

关键词： TPO卷材焊接剥离强度热风焊接影响因素

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Mechanism of Survivin Gene Expression in the Process of Inhibiting Breast Cancer Cell by Grape Seed Extract

Mechanism of Survivin Gene Expression in the Process of Inhi...

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华东六省一市生物化学与分子生物学会2008年学术交流会

作者： Chen Changjie Liu chenbiao yang Qingling Zhang Ju (Clinical testing and diagnose experimental center of Bangbu Medical College,An Hui,233000)

Grape seed extract (GSE) is a kind of effective antioxidant. The research indicates that GSE is also effective in preventing tumor. The molecular mechanism of a GSE anti-tumor effect is not absolutely clear. This rese...

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Vibration properties of Paulownia wood for Ruan sound quality using machine learning methods

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Journal of Forestry Research 2024年第5期35卷 216-222页

作者： yang yang College of Art and Design Harbin UniversityHarbin 150076People’s Republic of China College of Mechanical and Electrical Engineering Northeast Forestry UniversityHarbin 150040People’s Republic of China

As an important material for manufacturing resonant components of musical instruments,Paulownia has an important influence on the sound quality of *** this paper,a model for evaluating the sound quality of Ruan based on the vibration characteristics of wood is developed using machine learning ***,the selection of materials for Ruan manufacturing relies primarily on manually weighing,observing,striking,and listening by the instrument *** in scientific theory have hindered the quality of the finished *** this study,nine Ruans were manufactured,and a prediction model of Ruan sound quality was proposed based on the raw material information of *** of a total of 180 data sets,145 and 45 sets were chosen for training and validation,*** this paper,typical correlation analysis was used to determine the correlation between two single indicators in two adjacent pairwise combinations of the measured objects in each stage of the production process in *** vibra-tion characteristics of the wood were tested,and a model for predicting the evaluation of Ruan’s acoustic qualities was developed by measuring the vibration characteristics of the resonating plate *** acoustic quality of the Ruan sound board wood was evaluated and predicted using machine learning model generalized regression neural *** results show that the prediction of Ruan sound quality can be achieved using Matlab simulation based on the vibration characteristics of the soundboard *** the model-predicted values were compared with the tradi-tional predicted results,it was found that the generalized regression neural network had good performance,achieving an accuracy of 93.8%which was highly consistent with the experimental *** was concluded that the model can accurately predict the acoustic quality of the Ruan based on the vibration performance of the soundboards.

关键词： Sound quality Wood vibration performance Paulownia wood Machine learning methods

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丁基自粘TPO屋面系统在光伏发电项目中的应用

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中国建筑防水 2023年第2期 24-27页

作者：杨琛彪陈秋渝科顺防水科技股份有限公司广东佛山528300

相比于一般屋面,光伏屋面系统对整体的防水效果要求更高。本文介绍了德阳东方锅炉厂压型钢板屋面防水改造并加装光伏发电项目所采用的丁基自粘TPO屋面系统的特点与优势、施工工艺流程以及细部节点处理做法。

关键词：压型钢板屋面屋面改造光伏屋面防水系统丁基自粘TPO卷材

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Fresh-Keeping Decision and Coordination of Fresh Agricultural Product Supply Chain Considering Carbon Cap-and-Trade under Different Dominance

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Journal of Systems Science and Systems Engineering 2024年第1期33卷 30-51页

作者： yang yang Guanxin Yao China Institute for Agricultural Equipment Industrial Development Jiangsu UniversityZhenjiang212013China Jiangsu Modern Logistics Research Base Yangzhou UniversityYangzhou225009China

In the context of low carbon,this paper discussed the impact of the carbon cap-and-trade policy on the fresh-keeping decision-making of two-echelon fresh agricultural product supply chains under different dominance,and designed cost-sharing contracts to coordinate the supply chain of fresh agricultural products dominated by suppliers and retailers *** results showed that:dominance has no effect on the fresh-keeping decision and total revenue of fresh agricultural product supply chain,but it affects the internal income distribution,and dominance does not always bring more benefits;the implementation of carbon cap-and-trade reduces the fresh-keeping decision-making of fresh agricultural products supply chain and reduces the free-rider income of followers;the role of higher carbon trading price is twofold,which not only brings about the speculation of leading enterprises,but also promotes the application of low-carbon technologies;consumers’high preference for freshness,low-cost and high-efficiency low-carbon technology are all conducive to improving the fresh-keeping efforts and benefits of the supply chain;cost-sharing contracts can coordinate the supply chain of fresh agricultural products.

关键词： Dominant power carbon cap-and-trade policy fresh agricultural product supply chain fresh-keeping decision-making

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Overview of radar detection methods for low altitude targets in marine environments

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Journal of Systems Engineering and Electronics 2024年第1期35卷 1-13页

作者： yang Yong yang Boyu School of Electronic Science National University of Defense TechnologyChangsha 410073China

In this paper,a comprehensive overview of radar detection methods for low-altitude targets in maritime environments is presented,focusing on the challenges posed by sea clutter and multipath *** performance of the radar detection methods under sea clutter,multipath,and combined conditions is categorized and summarized,and future research directions are outlined to enhance radar detection performance for low-altitude targets in maritime environments.

关键词： radar sea clutter multipath scattering detection low altitude target

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Selective nano-buckling improves the performance of graphene logic transistors

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National Science Review 2024年第2期11卷 95-96页

作者： Tong yang Ming yang Department of Applied Physics The Hong Kong Polytechnic University Research Centre for Nanoscience and Nanotechnology The Hong Kong Polytechnic University

The massive integration of silicon-based transistors into modern electronic devices greatly increases power consumption and heat generation/dissipation[1]. In this concern, transistors based on atomically-thin graphene that exhibit high electric and thermoelectric conductivities with negligible contact resistance,

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Design Optimization and Operating Performance of S-CO_(2) Brayton Cycle under Fluctuating Ambient Temperature and Diverse Power Demand Scenarios

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Journal of Thermal Science 2024年第1期33卷 190-206页

作者： yang Jingze yang Zhen DUAN Yuanyuan Key Laboratory for Thermal Science and Power Engineering of MOE Beijing Key Laboratory for CO_(2) Utilization and Reduction TechnologyTsinghua UniversityBeijing 100084China

The supercritical CO_(2)(S-CO_(2)) Brayton cycle is expected to replace steam cycle in the application of solar power tower system due to the attractive potential to improve efficiency and reduce *** the concentrated solar power plant with thermal energy storage is usually located in drought area and used to provide a dispatchable power output,the S-CO_(2) Brayton cycle has to operate under fluctuating ambient temperature and diverse power demand *** addition,the cycle design condition will directly affect the off-design *** this work,the combined effects of design condition,and distributions of ambient temperature and power demand on the cycle operating performance are analyzed,and the off-design performance maps are proposed for the first time.A cycle design method with feedback mechanism of operating performance under varied ambient temperature and power demand is introduced *** show that the low design value of compressor inlet temperature is not conductive to efficient operation under low loads and sufficient output under high ambient *** average yearly efficiency is most affected by the average power demand,while the load cover factor is significantly influenced by the average ambient *** multi-objective optimization,the optimal solution of designed compressor inlet temperature is close to the minimum value of35℃ in Delingha with low ambient temperature,while reaches 44.15℃ in Daggett under the scenario of high ambient temperature,low average power demand,long duration and large value of peak load during the peak temperature *** the cycle designed with compressor inlet temperature of 35℃ instead of 44.15℃ in Daggett under light industry power demand,the reduction of load cover factor will reach 0.027,but the average yearly efficiency can barely be improved.

关键词： supercritical CO_(2)Brayton cycle ambient temperature fluctuating power demand scenarios design optimization off-design performance

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A physics-informed deep learning framework for spacecraft pursuit-evasion task assessment

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Chinese Journal of Aeronautics 2024年第5期37卷 363-376页

作者： Fuyunxiang yang Leping yang Yanwei ZHU College of Aerospace Science and Engineering National University of Defense TechnologyChangsha 410073China

Qualitative spacecraft pursuit-evasion problem which focuses on feasibility is rarely studied because of high-dimensional dynamics,intractable terminal constraints and heavy computational *** this paper,A physics-informed framework is proposed for the problem,providing an intuitive method for spacecraft threat relationship determination,situation assessment,mission feasibility analysis and orbital game rules *** the first time,situation adjustment suggestions can be provided for the weak player in orbital ***,a dimension-reduction dynamics is derived in the line-of-sight rotation coordinate system and the qualitative model is determined,reducing complexity and avoiding the difficulty of target set presentation caused by individual ***,the Backwards Reachable Set(BRS)of the target set is used for state space partition and capture zone ***-time analysis can eliminate the influence of changeable initial state and enable the proposed framework to analyze plural situations ***,a time-dependent Hamilton-Jacobi-Isaacs(HJI)Partial Differential Equation(PDE)is established to describe BRS evolution driven by dimension-reduction dynamics,based on level set ***,Physics-Informed Neural Networks(PINNs)are extended to HJI PDE final value problem,supporting orbital game rules summarization through capture zone evolution ***,numerical results demonstrate the feasibility and efficiency of the proposed framework.

关键词： Spacecraft pursuit-evasion Qualitative differential game Physics-Informed Neural Networks(PINNs) Reachability analysis Hamilton-Jacobi-Isaacs(HJI) Partial Differential Equations(PDEs)

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