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Feasibility analysis of 3D printed concrete with sludge incineration slag: Mechanical properties and environmental impacts

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CONSTRUCTION AND BUILDING MATERIALS 2024年 449卷

作者： Shen, Kaige Ding, Tao Cai, Chen Xiao, Jianzhuang Xiao, xuwen liang, Wan Tongji Univ Coll Civil Engn Dept Struct Engn Shanghai 200092 Peoples R China Tongji Univ Coll Environm Sci & Engn Shanghai 200092 Peoples R China Tongji Univ Inst Carbon Neutral Shanghai 200092 Peoples R China Shanghai Guohui Environm Protect Technol Grp Co Lt Shanghai 201702 Peoples R China

This study substituted sludge incineration slag for natural sand in the application of 3D printed concrete technology (3DCP). It analyzed the influence of the sludge incineration slag incorporation on the workability, printability, mechanical properties, and the solidifying effect of heavy metals in 3DCP. Furthermore, the environmental and economic benefits were also examined. The results indicated that the incorporation of sludge incineration slag accelerated the loss of workability factors such as flowability and consistency in 3DCP. However, it significantly enhanced the early strength of 3DCP and improved its buildability. Additionally, the addition of sludge incineration slag diminished the mechanical properties of 3DCP. When the substitution rate reached 50 % of natural sand with sludge incineration slag, the strength of the 3D printed specimens decreased by 22.1 %. Experimental investigations at a micro-scale indicated that the porosity of interlayer interfaces was a crucial factor causing strength reduction and could be ameliorated by appropriately increasing the extrusion amount to address excessive pore sizes. Toxicity leaching tests for heavy metals demonstrated that the maximum heavy metal leaching concentration in 3DCP specimens with sludge incineration slag incorporation was 0.14 mg/ L, meeting the specified requirements. The 3DCP with sludge incineration slag incorporation not only addressed the difficulty in handling incineration bottom slag but also conserved natural sand resources, presenting outstanding environmental and economic benefits. For instance, by substituting 100 % natural sand with sludge incineration slag, there were 5 % reduction in carbon emissions and 30 % increase in economic benefits.

关键词： 3D-printed concrete Sludge incineration slag Printability Mechanical properties Environmental benefits

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3D printed concrete with sewage sludge ash: Fresh and hardened properties

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CEMENT & CONCRETE COMPOSITES 2024年 148卷

作者： Ding, Tao Shen, Kaige Cai, Chen Xiao, Jianzhuang Xiao, xuwen liang, Wan Tongji Univ Coll Civil Engn Dept Struct Engn Shanghai 200092 Peoples R China Tongji Univ Coll Environm Sci & Engn Shanghai 200092 Peoples R China Tongji Univ Inst Carbon Neutral Shanghai 200092 Peoples R China Shanghai Guohui Environm Protect Technol Grp Co Lt Shanghai 201702 Peoples R China

In this study, the possibility of application of sewage sludge ash (SSA) in 3D printed concrete (3DCP) technology was explored. The replacement of partial cement with SSA in the concrete mix design was investigated, followed by a comprehensive analysis of its impact on the workability, printability, and mechanical properties of the 3DCP. The findings indicated that the incorporation of SSA accelerated the loss of workability of 3DCP, such as fluidity and consistency. However, it significantly improved the green strength and buildability. Further investigation revealed that the addition of SSA hampered the hydration process of cement, resulting in a reduction in the mechanical properties of the hardened material. CT scanning indicated that the addition of SSA increased the interlayer porosity, leading to further degradation of the mechanical properties. The toxicity characteristic leaching procedure demonstrated that the maximum leaching concentration of 3DCP incorporating SSA was 0.14 mg/L. This result confirmed the effective immobilization of heavy metals, fulfilling the prerequisites for the application of 3DCP incorporating SSA.

关键词： 3D printed concrete Sewage sludge ash Workability Printability Mechanical properties

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Direct Arylation Polycondensation of β-Fluorinated Bithiophenes to Polythiophenes: Effect of Side Chains in C-Br Monomers

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MACROMOLECULES 2022年第18期55卷 8095-8105页

作者： Zhang, xuwen Shi, Yibo Dang, Yanfeng liang, Ziqi Wang, Zhongli Deng, Yunfeng Han, Yang Hu, Wenping Geng, Yanhou Tianjin Univ Sch Mat Sci & Engn Tianjin 300072 Peoples R China Tianjin Univ Tianjin Key Lab Mol Optoelect Sci Tianjin 300072 Peoples R China Collaborat Innovat Ctr Chem Sci & Engn Tianjin Sch Mat Sci & Engn Tianjin 300072 Peoples R China Tianjin Univ Dept Chem Tianjin 300072 Peoples R China Collaborat Innovat Ctr Chem Sci & Engn Tianjin Tianjin Key Lab Mol Optoelect Sci Tianjin 300072 Peoples R China Tianjin Univ Natl Univ Singapore Joint Sch Int Campus Fuzhou 350207 Peoples R China Tianjin Univ Int Campus Fuzhou 350207 Peoples R China

Six polythiophenes (PThs) were synthesized via direct arylation polycondensation (DArP) with beta-fluorinated bithiophenes, that is, 4,4' -difluoro-2,2'-bithiophene (2FBT) and 3,3',4,4'-tetrafluoro-2,2'-bithiophene (4FBT), as the C-H monomers and 5,5'-dibromo-2,2'-bithiophenes DCBT-2Br, DABT-2Br, and DTBT-2Br that carry alkoxycarbonyl, alkyl, and alkylthienyl side chains at 4,4'-positions, respectively, as the C-Br monomers. Both 2FBT and 4FBT are highly reactive for DArP, and high molecular weight PThs with unobservable chain defects were successfully synthesized from 2FBT/DCBT-2Br, 2FBT/DABT-2Br, 2FBT/DTBT-2Br, and 4FBT/DTBT-2Br. However, the DArP of 4FBT with DCBT-2Br and DABT-2Br produced PThs containing C-H/C-H homo-coupling defects along with relatively lower molecular weights. Detailed theoretical analysis suggests that the occurrence of C-Br reduction-provoked C-H/C-H homo-coupling for 4FBT/DCBT-2Br and 4FBT/DABT-2Br monomer pairs originated from the poor selectivity between the cis- and trans-forms of transition states in the concerted metalation-deprotonation (CMD) process is responsible for the formation of structural defects and depressed molecular weights. This research reveals that a C-H monomer with high reactivity and selectivity is not sufficient for the synthesis of well-defined conjugated polymers via DArP, and the structure of the C-Br monomer also has a significant impact on the results of DArP via influencing the catalytic cycles.

关键词： Defects Monomers Polymerization Polymers Selectivity

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Evaluation of Efficiency Enhancement for a Solar Panel Using Water, Ice and Dry Ice Backside Cooling Systems 12

Evaluation of Efficiency Enhancement for a Solar Panel Using...

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12th International Electrical Engineering Congress, iEECON 2024

作者： Chaisuwan, Tawinwika Wei, Shuguang Khemkladmuk, Banri Srisombat, Supasin liang, Raohuai Zheng, xuwen Chanwiset, Aisawan Lertlam, Krit Photong, Chonlatee Mahasarakham University Faculty Of Engineering Maha Sarakham Thailand School Of Physics And Electronics Nanning Normal University Guangxi China

ISBN: (纸本)9798350383591

The purpose of this research is to study and conduct an experimental test for investigating the increase of efficiency of a solar panel when cooling it with a backside cooling system. There were 3 experiment test-rigs by using 3 different refrigerants: water, ice, and dry ice. By containing a type of refrigerant into its identical box that was designed by wrapping insulation around the box while drilling the holes for the box that did not contain any refrigerant. Then covered the box with a solar panel. To determine which refrigerant could be the best helped increase the efficiency of a solar panel. The research team conducted the tests with 2 time periods: a short time for 1 hour operation when collecting experimental results for every 2 minutes and a long time for 6 hours when collecting experimental results every 10 minutes. It is found from the experimental tests that significantly different capacity in power generated for different types of refrigerants could be obviously noticed even for the short time. For the long-time test, ice was the best refrigerant that continuously enhanced the efficiency for the solar panel with 25.2 watts compared with 24.0 watts for no refrigerant cooling, which was 6.25% increase. © 2024 IEEE.

关键词： Refrigerants

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负载姜黄素可注射微球延缓椎间盘的退变

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中国组织工程研究 2023年第12期27卷 1884-1891页

作者：叶旭文顾勇陈亮苏州大学附属第一医院江苏省苏州市215000

背景:椎间盘退变机制复杂,炎症通路激活、炎症因子泛滥、活性氧过度积累等均可加速椎间盘退变进程。姜黄素是从中药材姜黄中提取的天然药物,具有抑制炎症、抗氧化应激等药理作用。目的:探讨负载姜黄素的缓释微球局部注射延缓大鼠椎间盘... 详细信息

背景:椎间盘退变机制复杂,炎症通路激活、炎症因子泛滥、活性氧过度积累等均可加速椎间盘退变进程。姜黄素是从中药材姜黄中提取的天然药物,具有抑制炎症、抗氧化应激等药理作用。目的:探讨负载姜黄素的缓释微球局部注射延缓大鼠椎间盘退变的疗效。方法:①采用微流控技术制备负载姜黄素的甲基丙烯酸酰化明胶缓释微球,评估其体外释药和降解情况;②将缓释微球与未载药微球分别与髓核细胞共培养,以单独培养的细胞为对照,将3组细胞分别培养于正常环境和氧化应激环境(加入H_(2)O_(2))中,通过CCK-8、活/死染色实验评估细胞的活性与增殖情况,qRT-PCR实验检测相关因子的表达水平;③将30只SD大鼠随机分为正常组、退变组、未载药微球组、姜黄素组、缓释微球组,每组6只,在大鼠尾椎7-8和8-9节段经皮穿刺建立椎间盘退变模型,未载药微球组、姜黄素组、缓释微球组退变的椎间盘内注射对应的溶液。4周后,通过影像学与组织学观察椎间盘组织结构改变。结果与结论:①缓释微球可缓慢持续释放姜黄素,至28 d时释放姜黄素总量为(84.11±2.71)%;在含有胶原酶的PBS中,缓释微球质量逐渐减小,至第5周时消失。②CCK-8和活/死染色实验显示,在正常环境下,缓释微球不会影响髓核细胞的增殖活力;在氧化应激环境下,相比未载药微球,缓释微球可维持髓核细胞的增殖活力。qRT-PCR实验显示,相较于正常环境,氧化应激环境激活了髓核细胞中多种炎症因子mRNA的过量表达;在氧化应激环境下,相较于未载药微球组与对照组,缓释微球组肿瘤坏死因子α、白细胞介素1β、白细胞介素6及基质金属蛋白酶3的mRNA表达降低,Ⅱ型胶原和蛋白聚糖的mRNA表达升高。③动物体内实验结果显示,未载药微球组4周后的影像学与组织学评估与退变组比较无明显差异;姜黄素组的椎间隙高度及MRI评分在第1周时较退变组和未载药微球组虽有一定程度改善,但在第4周时其影像学与组织学评估均不如缓释微球组。④结果表明,姜黄素缓释微球能够抑制H_(2)O_(2)诱导的髓核细胞凋亡、延缓椎间盘退变进程,其机制与抑制核因子κB通路、降低氧化应激水平有关。

关键词：微流控技术纳米粒微球冷冻干燥姜黄素椎间盘退变甲基丙烯酸酐化明胶

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基于玻璃纤维织物的固-固相变树脂复合材料制备及电磁屏蔽性能

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工程塑料应用 2024年第9期52卷 35-40页

作者：梁超博霍强强隋绪文中北大学材料科学与工程学院太原030051

具备灵活热响应的电磁干扰(EMI)屏蔽复合材料是电磁防护、建筑工程、电子兼容等领域的理想候选材料之一。为制得该类EMI屏蔽复合材料,首先将异氰酸丙基三乙氧基硅烷(IPTS)与聚乙二醇(PEG)反应,获得具有高活性硅醇基团可自交联的柔韧固-... 详细信息

具备灵活热响应的电磁干扰(EMI)屏蔽复合材料是电磁防护、建筑工程、电子兼容等领域的理想候选材料之一。为制得该类EMI屏蔽复合材料,首先将异氰酸丙基三乙氧基硅烷(IPTS)与聚乙二醇(PEG)反应,获得具有高活性硅醇基团可自交联的柔韧固-固相变树脂(SPCR)基体,随后,通过SPCR封装被银纳米线(AgNWs)修饰的玻璃纤维织物(GFF)制备得到AgNWs/GFF/SPCR复合材料。测试了SPCR的结构和热稳定性,研究了AgNWs/GFF层数对复合材料电磁屏蔽性能的影响,最后测试了复合材料的热响应性能。结果表明,SPCR在保留原始PEG相变特性的同时具有优异的形状稳定能力,从而避免被泄漏。4层AgNWs/GFF组成的复合材料在2.8 mm厚度下的EMI屏蔽效能(SE)约为73 dB。电磁波吸收效能(SEA)随着EMI SE的增加呈现出递增的趋势,而电磁波反射效能(SER)在6~18 dB范围内波动。同时,反射系数(R)远大于吸收系数(A),AgNWs/GFF/SPCR复合材料表现出明显的反射主导屏蔽机制。此外,AgNWs/GFF/SPCR复合材料在升温和降温过程均表现出明显的温度滞后现象。因此,AgNWs/GFF/SPCR复合材料在电磁辐射防护和设备热管理方面具有广阔的前景。

关键词：固-固相变树脂聚乙二醇银纳米线玻璃纤维织物电磁屏蔽

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Adaptable graphitic C6N6-based copper single-atom catalyst for intelligent biosensing

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NATURE COMMUNICATIONS 2023年第1期14卷 1-11页

作者： Hong, Qing Yang, Hong Fang, Yanfeng Li, Wang Zhu, Caixia Wang, Zhuang liang, Sicheng Cao, xuwen Zhou, Zhixin Shen, Yanfei Liu, Songqin Zhang, Yuanjian Southeast Univ Sch Chem & Chem Engn Jiangsu Engn Lab Smart Carbon Rich Mat & Device Jiangsu Prov Hitech Key Lab Biomed Res Nanjing 211189 Peoples R China Southeast Univ Med Sch Nanjing 210009 Peoples R China

Self-adaptability is highly envisioned for artificial devices such as robots with chemical noses. For this goal, seeking catalysts with multiple and modulable reaction pathways is promising but generally hampered by inconsistent reaction conditions and negative internal interferences. Herein, we report an adaptable graphitic C6N6-based copper single-atom catalyst. It drives the basic oxidation of peroxidase substrates by a bound copper-oxo pathway, and undertakes a second gain reaction triggered by light via a free hydroxyl radical pathway. Such multiformity of reactive oxygen-related intermediates for the same oxidation reaction makes the reaction conditions capable to be the same. Moreover, the unique topological structure of CuSAC6N6 along with the specialized donor-pi-acceptor linker promotes intramolecular charge separation and migration, thus inhibiting negative interferences of the above two reaction pathways. As a result, a sound basic activity and a superb gain of up to 3.6 times under household lights are observed, superior to that of the controls, including peroxidase-like catalysts, photocatalysts, or their mixtures. CuSAC6N6 is further applied to a glucose biosensor, which can intelligently switch sensitivity and linear detection range in vitro. Catalysts with multiple and modulable reaction pathways are promising but generally hampered by inconsistent reaction conditions and negative internal interferences. Herein, the authors report an adaptable graphitic C6N6-based copper singleatom catalyst

关键词： Bioanalytical chemistry Biocatalysis Materials for energy and catalysis

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A New and Accurate Method for the Frequency Estimation of Complex Exponential Signals

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IEICE TRANSACTIONS ON FUNDAMENTALS OF ELECTRONICS COMMUNICATIONS AND COMPUTER SCIENCES 2017年第5期E100A卷 1231-1235页

作者： Wu, Kang Chen, Yijun Hou, Huiling Chen, Wenhao liang, xuwen Chinese Acad Sci Shanghai Inst Microsyst & Informat Technol Shanghai Peoples R China Chinese Acad Sci Shanghai Engn Ctr Microsatellites Shanghai Peoples R China

In this letter, a new and accurate frequency estimation method of complex exponential signals is proposed. The proposed method divides the signal samples into several identical segments and sums up the samples belonging to the same segment respectively. Then it utilizes fast Fourier transform (FFT) algorithm with zero-padding to obtain a coarse estimation, and exploits three Fourier coefficients to interpolate a fine estimation based on least square error (LSE) criterion. Numerical results show that the proposed method can closely approach the Cramer-Rao bound (CRB) at low signal-to-noise ratios (SNRs) with different estimation ranges. Furthermore, the computational complexity of the proposed method is proportional to the estimation range, showing its practical-oriented ability. The proposed method can be useful in several applications involving carrier frequency offset (CFO) estimation for burst-mode satellite communications.

关键词： frequency estimation different estimation ranges low SNR CRB

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Comparison of whole-body 18F-FDG PET/CT and PET/MRI for distant metastases in patients with malignant tumors: a meta-analysis

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BMC CANCER 2023年第1期23卷 37-37页

作者： Zhang, Cici liang, Zhishan Liu, Wei Zeng, xuwen Mo, Yuzhen Guangzhou Red Cross Hosp Dept Radiol Guangzhou Peoples R China Peoples Hosp Guangxi Zhuang Autonomous Reg Dept Cardiol Nanning Peoples R China Guangzhou Red Cross Hosp Dept Breast Guangzhou Peoples R China 396 TongFu Rd HaiZhu Dist Guangzhou Guangdong Peoples R China

Background As a first-line imaging modality, whole-body fluorine-18 fluorodeoxyglucose (18F-FDG) positron emission tomography (PET)/computed tomography (CT) and 18F-FDG PET/magnetic resonance imaging (MRI) had been widely applied in clinical practice. However, 18F-FDG PET/MRI may be superior to PET/CT for the diagnosis of distant metastases in patients with advanced-stage. Therefore, it is timely and important to systematically determine the diagnostic accuracy of 18F-FDG PET/MRI compared with that of 18F-FDG PET/CT for the diagnosis of distant *** This study aimed to compare the diagnostic accuracy of 18F-FDG PET/CT and PET/MRI for the diagnosis of distant metastases in patients with malignant tumors. Relevant studies using both 18F-FDG PET/CT and PET/MRI for assessment of distant metastases in patients with malignant tumors were searched in PubMed, Embase, The Cochrane Library, and Scopus from January 2010 to November 2023. Two reviewers independently selected studies according to the inclusion and exclusion criteria. A reviewer extracted relevant data and assessed the quality of the eligible studies. The pooled sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, and area under the summary receiver operating characteristic curve (AUC) for 18F-FDG PET/CT and PET/MRI were analyzed. Subgroup analysis was *** Across 14 studies (1042 patients), 18F-FDG PET/MRI had a higher sensitivity (0.87 versus 0.81), AUC value (0.98 versus 0.95), and similar specificity (0.97 versus 0.97), than PET/CT for detecting distant metastases. In 3 studies of breast cancer (182 patients), 18F-FDG PET/MRI had a higher sensitivity (0.95 versus 0.87) and specificity (0.96 versus 0.94) than PET/CT. In 5 studies of lung cancer (429 patients), 18F-FDG PET/CT had a higher sensitivity (0.87 versus 0.84) and a lower specificity (0.95 versus 0.96) to PET/*** 18F-FDG PET/MRI and PET/CT both performed well as detectors of distant meta

关键词： Tumor Distant metastases Positron emission tomography magnetic resonance imaging computed tomography

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Altered levels of circulating CD8⁺CXCR5⁺PD-1⁺T follicular cytotoxic cells in primary Sjogren's syndrome

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CLINICAL RHEUMATOLOGY 2022年第6期41卷 1697-1708页

作者： Zhai, xuwen Wang, Yanlin Guo, Hui liang, Zhaojun Feng, Min Wu, Yanyao Qin, Yan Zhao, Xiangcong Gao, Chong Luo, Jing Shanxi Med Univ Simulat Hosp Clin Skills Teaching Jinzhong 030600 Shanxi Peoples R China Shanxi Med Univ Dept Med Div Rheumatol Hosp 2 Taiyuan 030001 Shanxi Peoples R China Shanxi Med Univ Dept Med Div Nephrol Hosp 2 Taiyuan 030001 Shanxi Peoples R China Shenzhen Baoan Shiyan Peoples Hosp Dept Med Div Nephrol Shenzhen 518005 Guangdong Peoples R China Harvard Med Sch Brigham & Womens Hosp Dept Pathol Boston MA 02115 USA

Background Circulating CD8(+)T-cells expressing the C-X-C chemokine receptor type 5 (CXCR5) (CD8(+)CXCR5(+)T), a recently identified follicular cytotoxic T cell subset, are involved in antiviral immunity and autoimmunity, but their abundance and role in the pathogenesis of primary Sjogren syndrome (pSS) are unknown. Methods Circulating CD8(+)CXCR5(+)T cell and CD8(+) regulatory T cells (CD8(+)Treg) were evaluated in 49 pSS patients (19 patients with pulmonary involvement) and 24 age- and sex-matched healthy controls (HCs) by flow cytometry. Orthogonal partial least squares discriminant analysis (OPLS-DA) was performed, and receiver operating characteristic curves (ROC) were generated to identify characteristic cell subsets. Spearman's correlation analysis was conducted to examine the relationships between CD8(+)T cell subsets and clinical features. Results The proportions and numbers of CD8(+)CXCR5(+) , CD8(+)CXCR5(+) programmed death 1-positive (PD-1(+)), and CD8(+)CXCR5 PD-1(+)T cells were significantly higher, whereas those of CD8 +/- Treg were markedly lower, in pSS patients than HCs. The CD8(+)CXCR5(+)PD-1(+)T cell to CD8(+)Treg ratio had the greatest discriminatory power for pSS and HCs according to OPLS-DA and ROC analyses. The increased numbers of CD8(+)CXCR5(+)T cells and CD8(+)CXCR5(+)PD-1(+)T cells were strongly associated with those of CD4(+)CXCR5(+)T and B cells. The proportions and numbers of CD8(+)CXCR5(+)PD-1(+)T cells were increased in pSS patients with lung involvement. Conclusions We identified a new CD8(+)CXCR5(+)PD-1(+)T subset, which was increased in abundance in pSS patients, particularly those with lung involvement, compared with HCs. Also, the CD8(+)CXCR5(+)PD-1(+)T to CD8(+)Treg ratio may be useful for identifying pSS. Our findings suggest that targeting follicular CD8(+)T cell subsets has therapeutic potential for pSS.

关键词： CD8(+)CXCR5(+) follicular cytotoxic T subsets CD8(+) regulatory T cells Lung involvement OPLS-DA Primary Sjogren's syndrome

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