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Exo-Selective Intramolecular c-H Alkylation with 1,1-Disubstituted Alkenes by Rare-Earth catalysts: construction of Indanes and Tetralins with an All-carbon Quaternary center

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AcS cATALYSIS 2022年第20期12卷 12973-12983页

作者： Mishra, Aniket Wu, Ping cong, Xuefeng Nishiura, Masayoshi Luo, Gen Hou, Zhaomin RIKEN Ctr Sustainable Resource Sci Adv Catalysis Res Grp Wako Saitama 3510198 Japan Anhui Univ Inst Phys Sci & Informat Technol Hefei 230601 Peoples R China RIKEN Organometall Chem Lab Cluster Pioneering Res Wako Saitama 3510198 Japan

We report herein the exo-selective, regiospecific annulation of a wide range of functionalized aromatic substrates with 1,1-disubstituted alkenes through c(sp2)-H and benzylic c(sp3)-H activation by half-sandwich rare-earth catalysts. This protocol offers a straightforward and atom-efficient route for the synthesis of a family of indane and tetralin derivatives bearing an all-carbon quaternary stereocenter that were difficult to access previously by other catalysts. The reaction mechanism has been elucidated by deuterium-labeling experiments and DFT calculations.

关键词： annulation c H activation all-carbon quaternary center scandium yttrium rare-earth-metal

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Anaerobic co-digestion using poultry slaughterhouse and vegetable wastes to enhance biogas yield: effect of different c/N ratios

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BIOMASS cONVERSION AND BIOREFINERY 2022年第22期14卷 28303页

作者： Samadi, Mohammad Taghi Leili, Mostafa Rahmani, Alireza Moradi, Samira Godini, Kazem Hamadan Univ Med Sci Res Ctr Hlth Sci Dept Environm Hlth Engn Hamadan Hamadan Iran Kurdistan Univ Med Sci Environm Hlth Res Ctr Res Inst Hlth Dev Sanandaj Iran

The aim of this study was to determine the feasibility of producing biogas by combining solid poultry slaughterhouse wastes (SPSWs) with fruit and vegetable solid wastes (FVSWs) and to obtain the optimum conditions for maximum biogas production by means of anaerobic digestion (AD). The ratio of available carbon to available nitrogen (c/N), as a critical parameter in producing methane, was adjusted by mixing the appropriate amount of SPSWs with FVSWs. For each load, a 50-L pilot-scale digester was operated for 40 days. For start-up and seeding, the biogas reactor was bioaugmented using the anaerobic sludge of an industrial poultry wastewater treatment plant. The analyzed SPSW, which had a c/N ratio of 5.75, was combined with FVSWs to obtain c/N ratios of 20, 30, and 40. Furthermore, it was found that the highest biogas yield occurred when the c/N ratio of the feed was 30. Also, for all three loading ratios, biogas production volumes were 215.1, 241, and 182.7 L, respectively, where methane's shares were 104.5, 120.6, and 91.7 L of the total gas volume that constituted 48.6, 50, and 50.2% of the produced biogas. Therefore, the obtained results from the process of mesophilic AD of this type of solid wastes illustrate that it is possible to efficiently produce biogas as a renewable energy source by combining SPSWs and FVSWs, instead of burning or burying them.

关键词： Anaerobic digestion Biogas Poultry slaughterhouse wastes c N ratio

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Enhanced electrochemical performance of LiFePO4/c wrapped with sulfur-modified reduced graphene oxide for Li-ion batteries

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IONIcS 2022年第1期28卷 191-200页

作者： chen, Zi-Liang Gu, Yi-Jing Luo, Gui-Yang Huo, Yong-Lin Wu, Fu-Zhong Guizhou Univ Coll Mat & Met Guizhou Prov Key Lab Met Engn & Proc Energy Savin South Hua Xi St Guiyang 550025 Peoples R China

Although researchers have previously examined whether graphene modified by sulfur can improve the electrochemical performance of LiFePO4/c composites, they have rarely examined whether it can do so during the synchronous synthesis of LiFePO4/c and sulfur-modified reduced graphene oxide (SG) via a one-step hydrothermal method. To answer this question, a series of olivine structure LiFePO4/c composites wrapped with SG were investigated. Subsequently, we found that SG can form a three-dimensional conductive network on the surface of the LiFePO4/c sample. In the process, XRD and HRTEM tests were undertaken as well. From the XRD test, the results show that SG does not affect the olivine structure of LiFePO4/c. In the HRTEM experiment, clear lattice fringes and a uniformly coated carbon layer on the sample surface were observed. Alongside these results, there were 4 others. First, the charge-discharge data showed that the electrochemical performance of the samples could be increased by SG modification. Second, sample S2 with a mass ratio of Na2S to rGO of 1:10 shows the best specific discharge capacity and stability. Third, the specific capacity of S2 is 163 mAhg(-1) at 0.2 c, and the capacity retention is 108.23% even after 200 cycles at a magnification of 10 c. Fourth, according to EIS, the charge migrating resistance of S2 is 226.4 omega, and the lithium-ion diffusion coefficient is 2.41 x 10(-14) cm(2)center dot S-1. The significance of these results is that they indicate that wrapping LiFePO4/c with SG significantly contributed to the improvement of its electrochemical performance.

关键词： Lithium-ion battery LiFePO4 c S-modified reduced graphene oxide Electrochemical performance

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Electrical performance prediction of graphdiyne-c60 nanocomposite

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MRS cOMMUNIcATIONS 2022年第5期12卷 729-733页

作者： Hu, Yongle Gao, Shan Zhang, Zhang Guo, Juan Yang, Ping Changsha Univ Sci & Technol Hunan Prov Key Lab Intelligent Mfg Technol High P Changsha 410114 Peoples R China Jiangsu Univ Sch Mech Engn Lab Adv Design Mfg & Reliabil MEMS NEMS OEDS Zhenjiang 212013 Jiangsu Peoples R China

We investigated the field emission of graphdiyne-c-60 nanocomposite by using first principle calculation. The results show that graphdiyne obtains good electrical performances such as high level of emission currents. The construction with c-60 cluster and graphdiyne can take full advantages of the curvature effect and the tip effect of c-60 cluster which induces local charge improvement. It shows that the c-60 cluster can strengthen the field emission of graphdiyne-c-60 nanocomposite. It implies that the graphdiyne-c-60 nanofabrication could have a potential application for field emission electron sources in the future.

关键词： c computation/computing Electronic material Modeling Simulation

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Toward High-Performance cO2-to-c2 Electroreduction via Linker Tuning on MOF-Derived catalysts

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SMALL 2022年第18期18卷 2200720-2200720页

作者： chen, Rongzhen cheng, Ling Liu, Jinze Wang, Yating Ge, Wangxin Xiao, chuqian Jiang, Hao Li, Yuhang Li, chunzhong East China Univ Sci & Technol Sch Mat Sci & Engn Shanghai Engn Res Ctr Hierarch Nanomat Key Lab Ultrafine MatMinist Educ Shanghai 200237 Peoples R China East China Univ Sci & Technol Sch Chem Engn Shanghai 200237 Peoples R China

copper (cu)-based metal-organic frameworks (MOFs) and MOF-derived catalysts are well studied for electroreduction of carbon dioxide (cO2);however, the effects of organic linkers for the selectivity of cO2 reduction are still unrevealed. Here, a series of cu-based MOF-derived catalysts is investigated with different organic linkers appended, named X-cu-BDc (BDc = 1,4-benzenedicarboxylic acid, X = NH2, OH, H, F, and 2F). It is found that the linkers affect the faradaic efficiency (FE) for c-2 products with an order of NH2- < OH- < bare cu-BDc < F- < 2F-, thus tuning the FEc2:FEc1 ratios from 0.6 to 3.8. As a result, the highest c-2 FE of approximate to 63% at a current density of 150 mA cm(-2) on 2F-cu-BDc derived catalyst is achieved. Using operando Raman measurements, it is revealed that the MOF derives to cu2O during ecO(2)RR but organic linkers are stable. The fluorine group in organic linker can promote the H2O dissociation to *H species, further facilitating the hydrogenation of *cO to *cHO that helps c-c coupling.

关键词： c (2) products cO (2) electroreduction cu metal-organic frameworks organic linkers

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Experimental Study on Surface Quality in Ultrasonic-assisted Grinding of c/c-Zrc-cu composites Fabricated with Different Preforms

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APPLIED cOMPOSITE MATERIALS 2022年第5期29卷 1747-1769页

作者： Duan, Zhenyan chen, Tao Li, Hongbo Zhang, Yiwen Li, Haotian Wuhan Univ Technol Sch Mech & Elect Engn Wuhan 430070 Peoples R China

c/c-Zrc-cu composite is a new ablation-resistant material with wide application prospects in the aerospace field. The quality of its surface affects the ablative corrosion resistance of the material. Ultrasonic-assisted grinding (UAG) is an effective processing method for hard and brittle materials. Therefore, it is meaningful work to investigate the material removal mechanism of c/c-Zrc-cu composites in UAG. In this paper, UAG was applied to the processing of c/c-Zrc-cu composites fabricated with different preforms which include needle-punched preform, pierced preform and felt-based preform. The effects of process parameters on the surface quality of c/c-Zrc-cu composites fabricated with different preforms were investigated via single-factor tests. The machining tools used for the tests were the electroplated diamond grinding wheels and the ultrasonic vibration direction was parallel to the processed surface. The results indicate that the preforms determine the surface quality of the c/c-Zrc-cu composites. The surface quality of c/c-Zrc-cu composites fabricated with felt-based preform is the best because of the lower carbon fiber content. The removal of carbon fibers is mainly by brittle fracture, interface debonding and pull-out, and the removal of hard Zrc particles is mainly by brittle fracture while the cu-rich area is removed in a plastic manner. In addition, when the ultrasonic amplitude is in the range of 4-9 mu m, the hard Zrc particles are more easily broken thus deteriorating the surface quality.

关键词： c c-Zrc-cu composites Ultrasound-assisted grinding (UAG) The material removal mechanism Surface roughness

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Polystyrene nanoparticles cause dynamic alteration in mitochondrial unfolded protein response from parents to the offspring in c. elegans

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cHEMOSPHERE 2022年第Part1期308卷 136154页

作者： Xu, Ruoran Hua, Xin Rui, Qi Wang, Dayong Nanjing Agr Univ Coll Life Sci Nanjing 210095 Peoples R China Southeast Univ Med Sch Nanjing 210009 Peoples R China

The mitochondrial unfolded protein response (mt UPR) is important for organisms against the toxicity from toxicants and stresses. Polystyrene nanoparticle (PS-NP), one of the emerging pollutants, has aroused increasing concern for its toxicity in the offspring. Nevertheless, the molecular basis for this transgenerational toxicity remains largely unclear. In this study, the role of mt UPR in the induction of transgenerational toxicity was determined in caenorhabditis elegans (c. elegans) after parental exposure to PS-NP. After exposure to PS-NP (1-100 mu g/L), the suppression in mt UPR showed the concentration-dependent in nematodes from P0 genera-tion (P0-G) to F2-G. Moreover, the decreased expression of genes required for controlling mt UPR (atfs-1, dve-1, and ubl-5 genes) were observed from P0-G to F2-G after exposure to PS-NP (1 mu g/L). The adverse effects on locomotion and reproductive capacity were more severe over generations in nematodes with RNAi of these three genes, indicating that these genes were involved in controlling transgenerational toxicity. After parental PS-NP exposure (1 mu g/L), the mt UPR was significantly inhibited by RNAi of atfs-1, dve-1, and ubl-5, indicating the association between the transgenerational PS-NP toxicity and mt UPR suppression. Additionally, during the transgenerational process, RNAi of atfs-1, dve-1, and ubl-5 enhanced the PS-NP toxicity by suppressing mt UPR, while RNAi of daf-2 encoding an insulin receptor inhibited the PS-NP toxicity by increasing mt UPR. Therefore, our data highlighted the role of inhibition in mt UPR in mediating the transgenerational nanoplastic toxicity in nematodes.

关键词： Nanoplastic mt UPR Transgenerational response c elegans

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Effects of Void Defects on Fracture Features and Tensile Strength of c/Sic composites: an Image-based FEM Study

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APPLIED cOMPOSITE MATERIALS 2022年第3期29卷 1021-1039页

作者： Li, Qiubo chen, Yihui chen, Yanfei Ai, Shigang Fang, Daining Beijing Inst Technol Inst Adv Struct Technol Beijing 100081 Peoples R China

Manufacturing defects in ceramic matrix composites (cMcs), such as voids, microcracks, etc., significantly affect the damage events and strength of the materials. This study aims to reveal the effect of void defects on the failure behavior and tensile strength of a plain-woven c/Sic composite. The mesoscopic architectures of the c/Sic composites are tested by micro-computed tomography. Based on the mu-cT images of the material, finite element models (IB-FEM) of the c/Sic composite are established with different void volume fractions and different void geometry. The tensile strength and fracture features of the c/Sic composites are calculated by using the IB-FEM. The effects of void volume fraction and geometry on failure behaviors and tensile strength of the c/Sic composites are investigated and discussed. This study is of great significance for further understanding the influence of defects on the mechanical behavior of cMcs.

关键词： Image-based finite element method c Sic composite Void defect Tensile strength

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Architecting a 3D continuous c/cuVO3@cu composite anode for lithium-ion storage

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SURFAcE INNOVATIONS 2022年第1-3期11卷 70-78页

作者： Gou, Jinlong Qiao, Zhijun Yu, Zhenyang Sun, Shihao Li, chuanqi Li, Wei-Jie Wang, Jun Wang, Nan Zhang, Zhijia Jiang, Yong Tiangong Univ Sch Mech Engn Sch Mat Sci & EngnTianjin Municipal Key Lab Adv F State Key Lab Separat Membrane & Membrane Proc Tianjin Peoples R China Univ Wollongong Inst Superconducting & Elect Mat Wollongong Australia Shandong Univ Key Lab Liquid Solid Struct Evolut & Proc Mat Minist Educ Jinan Peoples R China China Elect Technol Grp Corp 46 Inst Tianjin Peoples R China CETC JH Tianjin Semicond Mat Co Ltd Tianjin Peoples R China

Vanadium (V)-based oxides with a high theoretical capacity are an alternative anode for lithium-ion (Li+) batteries, but they are still limited by the poor conductivity, large volume change and low active material mass loading. Herein, a three-dimensional (3D) continuous c/cuVO3@cu composite anode with high copper (II) metavanadate (IV) (cuVO3) mass loading is synthesized by the combination of high-energy ball milling, non-solvent-induced phase separation and heat treatment. The copper (cu) framework can enhance electron/ion conductivity in coordination with amorphous carbon (c). Furthermore, the macropore channels in the copper framework can provide buffer space for the volume expansion of active material copper (II) metavanadate (IV) during lithiation/delithiation. As a result, this 3D continuous c/cuVO3@cu composite anode achieves a high copper (II) metavanadate (IV) mass loading of about 3.8 mg/cm(2), delivering a reversible capacity of 479 mAh/g at 100 mA/g after 120 cycles. More importantly, a long life span is achieved with a reversible capacity of 268 mAh/g even after 1700 cycles at a high current density of 1000 mA/g, demonstrating excellent cycle performance. This work provides a way to develop 3D continuous composite material anodes with extraordinary electrochemistry performance for next-generation energy-storage devices.

关键词： c cuVO3@cu composite materials electrochemistry energy lithium-ion batteries

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Novel c/Sic porous ceramic with controllable properties served as transpiration cooling material

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cERAMIcS INTERNATIONAL 2022年第15期48卷 21616-21621页

作者： Zhang, Bo Wang, Han Jin, Xiaochao Fan, Xueling Huang, Haiming Yao, Jun Xi An Jiao Tong Univ Joint Res Ctr Extreme Environm & Protect Technol Xian Peoples R China Xi An Jiao Tong Univ Sch Aerosp Engn State Key Lab Strength & Vibrat Mech Struct Xian Peoples R China Beijing Jiaotong Univ Inst Engn Mech Beijing 100044 Peoples R China Sci & Technol Space Phys Lab Beijing 100071 Peoples R China

Transpiration cooling has been gradually regarded as one of the most efficient and potential thermal protection technologies for the high temperature hot-end components of future hypersonic vehicle. The cooling perfor-mance of this technology profoundly depends on the properties of porous medium. This paper exhibits a novel c/ Sic porous ceramic with controllable properties adjusted by molding pressure and carbon fiber content in the grinding-mold pressing-sintering process, and investigates the transpiration cooling performance using this ceramic with liquid water. Molding pressure improves from 50 MPa to 100 MPa, the compressive strength has increased by 52.9% and 67.9%, and the permeability decreases about 38% and 39.5% respectively corresponding to fiber content of 6% and 10%. The surface temperatures and back-side temperatures of porous ceramic with the largest molding pressure reaches the highest due to the lowest porosity which can reduce the heat exchange area between cooling water and porous ceramic skeleton. This novel porous ceramic with controllable characteristics can optimize the design of the transpiration cooling system.

关键词： c Sic porous ceramic controllable properties Transpiration cooling Molding pressure carbon fiber content

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