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All-inorganic TiO/CsAgBiBr composite as highly efficient photocatalyst under visible light irradiation

《化学科学与工程前沿（英文）》 2023年第17卷第12期页码 1925-1936 doi: 10.1007/s11705-023-2344-6

摘要： In recent years, limited photocatalysis efficiency and wide band gap have hindered the application of TiO₂ in the field of photocatalysis. A leading star in photocatalysis has been revealed as lead-free Cs₂AgBiBr₆ double halide perovskite nanocrystals, owing to its strong visible light absorption and tunable band gap. In this work, this photocatalytic process was facilitated by a unique TiO₂/Cs₂AgBiBr₆ composite, which was identified as an S-cheme heterojunction. TiO₂/Cs₂AgBiBr₆ composite was investigated for its structure and photocatalytic behavior. The results showed that when the perovskite dosage is 40%, the photocatalytic rate of TiO₂ could be boosted to 0.1369 min^–1. This paper discusses and proposes the band gap matching, carrier separation, and photocatalytic mechanism of TiO₂/Cs₂AgBiBr₆ composites, which will facilitate the generation of new ideas for improving TiO₂’s photocatalytic performance.

关键词： Cs₂AgBiBr₆ nanocrystals visible-light photocatalyst Cs₂AgBiBr₆/TiO₂ heterojunction

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Graphene-like -BN supported polyhedral NiS/NiS nanocrystals with excellent photocatalytic performance

《化学科学与工程前沿（英文）》 2021年第15卷第6期页码 1537-1549 doi: 10.1007/s11705-021-2094-2

摘要： Human health is deteriorating due to the effluent containing heavy metal ions and organic dyes. Hence, photoreduction of Cr(VI) to Cr(III) and degradation of rhodamine B (RhB) using a novel photocatalyst is particularly important. In this work, h-BN/NiS₂/NiS composites were prepared via a simple solvothermal method and a double Z-scheme heterojunction was constructed for efficiently removing RhB and Cr(VI). The 7 wt-% h-BN/NiS₂/NiS composites were characterized via a larger specific surface area (15.12 m²·g^–1), stronger light absorption capacity, excellent chemical stability, and high yield of electrons and holes. The experimental result indicated that the photoreduction efficiency of the 7 wt-% h-BN/NiS₂/NiS photocatalyst achieved 98.5% for Cr(VI) after 120 min, which was about 3 times higher than that of NiS₂/NiS (34%). However, the removal rate of RhB by the 7 wt-% h-BN/NiS₂/NiS photocatalyst reached 80%. This is due to the double Z-scheme heterojunction formed between NiS₂/NiS and h-BN, which improved the charge separation efficiency and transmission efficiency. Besides, the influence of diverse photogenerated electron and hole scavengers upon the photoreduction of Cr(VI) was studied, the results indicated that graphene-like h-BN promoted transportation of photoinduced charges on the surface of the h-BN/NiS₂/NiS photocatalyst via the interfacial effects.

关键词： graphene-like h-BN h-BN/NiS₂/NiS composites photocatalysis Cr(VI) reduction degradation of RhB

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Cytokine storm and translating IL-6 biology into effective treatments for COVID-19

《医学前沿（英文）》 doi: 10.1007/s11684-023-1044-4

摘要： As of May 3, 2023, the coronavirus disease 2019 (COVID-19) pandemic has resulted in more than 760 million confirmed cases and over 6.9 million deaths. Several patients have developed pneumonia, which can deteriorate into acute respiratory distress syndrome. The primary etiology may be attributed to cytokine storm, which is triggered by the excessive release of proinflammatory cytokines and subsequently leads to immune dysregulation. Considering that high levels of interleukin-6 (IL-6) have been detected in several highly pathogenic coronavirus-infected diseases, such as severe acute respiratory syndrome in 2002, the Middle East respiratory syndrome in 2012, and COVID-19, the IL-6 pathway has emerged as a key in the pathogenesis of this hyperinflammatory state. Thus, we review the history of cytokine storm and the process of targeting IL-6 signaling to elucidate the pivotal role played by tocilizumab in combating COVID-19.

关键词： SARS-CoV-2 COVID-19 cytokine storm interleukin-6 tocilizumab

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Cu-doped Bi/Bi₂WO₆ catalysts for efficient N₂ fixation by photocatalysis

《化学科学与工程前沿（英文）》 2023年第17卷第10期页码 1412-1422 doi: 10.1007/s11705-023-2312-1

摘要： In this paper, Cu-doped Bi₂WO₆ was synthesized via a solvothermal method and applied it in photocatalytic N₂ immobilization. Characterization results showed the presence of a small amount of metallic Bi in the photocatalyst, indicating that the synthesized photocatalyst is actually Bi/Cu-Bi₂WO₆ composite. The doped Cu had a valence state of +2 and most likely substituted the position of Bi³⁺. The introduced Cu did not affect the metallic Bi content, but mainly influenced the energy band structure of Bi₂WO₆. The band gap was slightly narrowed, the conduction band was elevated, and the work function was reduced. The reduced work function improved the transfer and separation of charge carriers, which mainly caused the increased photoactivity. The optimized NH₃ generation rates of Bi/Cu-Bi₂WO₆ reached 624 and 243 μmol·L^–1·g^–1·h^–1 under simulated solar and visible light, and these values were approximately 2.8 and 5.9 times higher those of Bi/Bi₂WO₆, respectively. This research provides a method for improving the photocatalytic N₂ fixation and may provide more information on the design and preparation of heteroatom-doped semiconductor photocatalysts for N₂-to-NH₃ conversion.

关键词： Bi₂WO₆ Cu doping work function photocatalytic N₂ fixation charge separation

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Function-reversible facets enabling SrTiO nanocrystals for improved photocatalytic hydrogen evolution

《能源前沿（英文）》 doi: 10.1007/s11708-023-0894-4

摘要： It has been widely reported that, for faceted nanocrystals, the two adjacent facets with different band levels contribute to promoted charge separation, and provide active sites for photocatalytic reduction and oxidation reaction, respectively. In such cases, only one family of facets can be used for photocatalytic hydrogen evolution. Herein, by using SrTiO₃ nanocrystals enclosed by {023} and {001} facets as a model photocatalyst, this paper proposed a strategy to achieve the full-facets-utilization of the nanocrystals for photocatalytic hydrogen via chemically depositing Pt nanoparticles on all facets. The photo-deposition experiment of CdS provided direct evidence to demonstrate that the {023} facets which were responsible for photooxidation reaction can be function-reversed for photocatalytic hydrogen evolution after depositing Pt nanoparticles, together with the {001} facets. Thus, the full-facets-utilization led to a much-improved activity for photocatalytic hydrogen, in contrast to those SrTiO₃ nanocrystals with only {001} facets deposited by Pt nanoparticles via a photo-deposition method.

关键词： SrTiO₃ nanocrystals crystal facets photocatalysis hydrogen evolution

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6G网络内生安全新范式探讨 Review

季新生1,2,3,邬江兴2,3,金梁2,黄开枝2,3,陈亚军2,孙小丽2,游伟2,霍树民2,杨静2

《信息与电子工程前沿（英文）》 2022年第23卷第10期页码 1421-1450 doi: 10.1631/FITEE.2200060

摘要：

6G网络将面临更为复杂的内生安全问题，亟需提出新的普适性安全理论，建立新的实践规范，以应对网络空间“未知的未知”安全威胁。本文首先阐述了网络空间内生安全发展的新范式，介绍了6G网络安全的需求愿景。进而详细分析了6G核心网、无线接入网、新兴使能技术等面临的安全问题，以及相应的安全技术发展现状，分析了内生安全与传统安全的融合发展，进而给出网络空间内生安全新范式指导下的相关安全理论与技术构想。

关键词： 6G安全；内生安全新范式；核心网；无线接入网

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Asymmetric transfer hydrogenation of prochiral ketone catalyzed over Fe-CS/SBA-15 catalyst

XUE Ping, WU Tao

《化学科学与工程前沿（英文）》 2007年第1卷第3期页码 251-255 doi: 10.1007/s11705-007-0045-1

摘要： A heterogeneous chiral catalyst Fe(III)-CS (chitosan) complex/mesoporous molecular sieve SBA-15 (Santa Barbara Amorphous) was prepared. The asymmetric transfer hydrogenations of prochiral acetophenone and 4-methyl-2-pentanone to corresponding chiral alcohols were carried out on Fe-CS/SBA-15 at atmosphere pressure using 2-propanol as hydrogen donor. Effects of Fe content in catalyst, reaction temperature, reaction time and promoter KOH concentration on the conversion of substrates and enantioselectivity were investigated. Fe-CS/SBA-15 with 2.2% mass fraction Fe exhibits considerable enantioselectivity and catalytic activity for the asymmetric transfer hydrogenations of aromatic ketone and aliphatic ketone. Under optimal reaction conditions: KOH concentration 0.03 mol/L, reaction temperature 70ºC and reaction time 4 h, enantiomer excess (ee) of ()-1-phenylethanol and conversion of acetophenone can reach 87.4% and 27.7%, respectively. Under the above KOH concentration and reaction temperature and reaction time of 8 h, the ee of ()-4-methyl-2-pentanol and conversion 4-methyl-2-pentanone amounted to 50.2% and 25.5%, respectively.

关键词： asymmetric transfer enantioselectivity Fe-CS/SBA-15 aliphatic aromatic

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Preparation and rheological behaviors of PA6/SiO2 nanocompiste

WEI Shanshan, LIU Yuejun, LI Xianggang, HUANG Yugang, WANG Xiayu, ZHANG Ping

《化学科学与工程前沿（英文）》 2007年第1卷第4期页码 332-337 doi: 10.1007/s11705-007-0060-2

摘要： The polyamide 6 (PA6)/SiO nanocomposites were prepared by in situ polymerization and the rheological behaviors were investigated. The morphology of resultant materials was characterized by scanning electron microscopy (SEM) and the rheological behaviors were characterized by capillary rheometer. The results showed that the SiO particle size was around 50 nm and the particles dispersed evenly in PA6 matrix. The nanocomposites were pesudoplastic fluids and the apparent viscosities of nanocomposites increased initially and then decreased with the increase in nano-SiO content at the same temperature. The non-Newtonian indexes of nanocomposites were smaller than those of pure PA6. With the increase in nano-SiO content the apparent viscous activation energies of nanocomposites increased initially and then decreased. The rheological behaviors revealed that there were strong interactions between PA6 macromolecule chains and nano-SiO particles.

关键词： polyamide temperature rheological activation pesudoplastic

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Single and joint effects of HHCB and cadmium on zebrafish (

Lei ZHANG, Jing AN, Qixing ZHOU

《环境科学与工程前沿（英文）》 2012年第6卷第3期页码 360-372 doi: 10.1007/s11783-011-0353-z

摘要： As an important type of emerging pollutants, ecological toxicity and risk of artificial musks are increasingly concerned. Thus, single and joint toxic effects of 1,3,4,6,7,8-hexahydro-4,6,6,7,8,8- hexamethylcyclopenta-gamma-2-benzopyran (HHCB) as one of the most widely applied artificial musks and cadmium (Cd) as an toxic metal on zebrafish ( ) were investigated by the exposure of zebrafish to various concentrations of HHCB or/and Cd in feculent water containing bedloads. The results indicated that the joint effect of HHCB and Cd changed during different exposure times within 120 h. The index of the antioxidant enzyme system including superoxide dismutase (SOD) and peroxidase (POD), and malondialdehyde (MDA) were sensitive and induced in the zebrafish stressed by Cd, and content of soluble protein (SP) was sensitive to HHCB and could be used as a biomarker for HHCB. Joint effects on antioxidant enzymes depended more on the effect of single Cd in the first one or two days. However, in the rest exposure days, the effect of HHCB began to dominate in the joint effect during the exposure process.

关键词： 1 3 4 6 7 8-hexahydro-4 6 6 7 8 8-hexamethylcyclopenta-gamma-2-benzopyran (HHCB) cadmium (Cd) antioxidant biomarker feculent water containing bedloads

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基于半导体纳米晶体的神经突触器件 Review

步明轩1,2,王越1,2,尹蕾1,2,童周禹1,2,张懿强3,杨德仁1,2,4,5,皮孝东1,2,4,5

《信息与电子工程前沿（英文）》 2022年第23卷第11期页码 1579-1601 doi: 10.1631/FITEE.2100551

摘要：

近年来，人们对信息处理的需求日益增长，脑启发式神经形态器件得到了广泛的关注。突触器件作为一类重要的神经形态器件，在短短几年内迅速升温。在用于制备突触器件的各种材料中，半导体纳米晶体（NCs）因其优异的电学和光学性能而成为首选材料之一。本综述论文首先介绍了基于半导体纳米晶体的突触器件的研究背景及半导体纳米晶体的基本性质。然后，根据器件有源层所用纳米晶体种类的不同，分类介绍了基于纳米晶体的突触器件的最新研究进展。最后，讨论了基于半导体纳米晶体的突触器件目前仍面临的问题和挑战。

关键词：半导体纳米晶体；突触器件；神经形态计算

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Gradient-based compressive image fusion

Yang CHEN,Zheng QIN

《信息与电子工程前沿（英文）》 2015年第16卷第3期页码 227-237 doi: 10.1631/FITEE.1400217

摘要： We present a novel image fusion scheme based on gradient and scrambled block Hadamard ensemble (SBHE) sampling for compressive sensing imaging. First, source images are compressed by compressive sensing, to facilitate the transmission of the sensor. In the fusion phase, the image gradient is calculated to reflect the abundance of its contour information. By compositing the gradient of each image, gradient-based weights are obtained, with which compressive sensing coefficients are achieved. Finally, inverse transformation is applied to the coefficients derived from fusion, and the fused image is obtained. Information entropy (IE), Xydeas’s and Piella’s metrics are applied as non-reference objective metrics to evaluate the fusion quality in line with different fusion schemes. In addition, different image fusion application scenarios are applied to explore the scenario adaptability of the proposed scheme. Simulation results demonstrate that the gradient-based scheme has the best performance, in terms of both subjective judgment and objective metrics. Furthermore, the gradient-based fusion scheme proposed in this paper can be applied in different fusion scenarios.

关键词： Compressive sensing (CS) Image fusion Gradient-based image fusion CS-based image fusion

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预腐蚀后拉伸超载对LC4CS铝合金疲劳性能的影响

蒋荟,杨晓华

《中国工程科学》 2006年第8卷第2期页码 44-46

摘要：

采用预腐蚀后进行单次拉伸超载疲劳试验的方法，研究了腐蚀与超载对LC4CS材料疲劳寿命的影响。

关键词： LC4CS 铝合金预腐蚀超载疲劳寿命

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Immobilization of nano-zero-valent irons by carboxylated cellulose nanocrystals for wastewater remediation

Bangxian Peng, Rusen Zhou, Ying Chen, Song Tu, Yingwu Yin, Liyi Ye

《化学科学与工程前沿（英文）》 2020年第14卷第6期页码 1006-1017 doi: 10.1007/s11705-020-1924-y

摘要： Nano-zero-valent irons (nZVI) have shown great potential to function as universal and low-cost magnetic adsorbents. Yet, the rapid agglomeration and easy surface corrosion of nZVI in solution greatly hinders their overall applicability. Here, carboxylated cellulose nanocrystals (CCNC), widely available from renewable biomass resources, were prepared and applied for the immobilization of nZVI. In doing so, carboxylated cellulose nanocrystals supporting nano-zero-valent irons (CCNC-nZVI) were obtained via an growth method. The CCNC-nZVI were characterized and then evaluated for their performances in wastewater treatment. The results obtained show that nZVI nanoparticles could attach to the carboxyl and hydroxyl groups of CCNC, and well disperse on the CCNC surface with a size of ~10 nm. With the CCNC acting as corrosion inhibitors improving the reaction activity of nZVI, CCNC-nZVI exhibited an improved dispersion stability and electron utilization efficacy. The Pb(II) adsorption capacity of CCNC-nZVI reached 509.3 mg·g (298.15 K, pH= 4.0), significantly higher than that of CCNC. The adsorption was a spontaneous exothermic process and could be perfectly fitted by the pseudo-second-order kinetics model. This study may provide a novel and green method for immobilizing magnetic nanomaterials by using biomass-based resources to develop effective bio-adsorbents for wastewater decontamination.

关键词： carboxylated cellulose nanocrystals nano-zero-valent irons magnetic bio-adsorbents wastewater remediation

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Propensity score-matched study and meta-analysis of cumulative outcomes of day 2/3 versus day 5/6 embryo

null

《医学前沿（英文）》 2017年第11卷第4期页码 563-569 doi: 10.1007/s11684-017-0535-6

摘要：

The superiority of the cumulative outcomes of day 5/6 embryo transfer to those of day 2/3 embryo transfer in infertile couples has been debated. This retrospective study included data collected from 1051 patients from July 2011 to June 2014. Multiple maternal baseline covariates were subjected to propensity score matching analysis, and each day 5/6 group woman was matched to one day 2/3 group woman. A systematic meta-analysis was conducted to validate the results. After matching was completed, 217 patients on the day 2/3 group were matched with those on the day 5/6 group, and no significant differences in the baseline characteristics were observed between the two groups. The cumulative pregnancy rate (57.14% vs. 53.46%, OR 1.16, 95% CI 0.79–1.70) and cumulative live birth rate (53.00% vs. 49.77%, OR 1.14, 95% CI 0.78–1.66) of day 5/6 embryo transfers were higher than those of day 2/3 embryo transfers, but this difference was not significant. The mean cycles per live birth and mean days per live birth in the day 5/6 group were significantly lower than those in the day 2/3 group. This study demonstrated that day 5/6 embryo transfer is a more cost-effective and time-efficient policy than day 2/3 embryo transfer to produce a live baby.

关键词： blastocyst embryo transfer cumulative pregnancy rate cumulative live birth rate IVF

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Sediment environmental capacity of 137Cs in Daya Bay

ZHANG Junli, CHEN Jiajun, XU Jialin, LI Yuanxin, HUANG Naiming

《环境科学与工程前沿（英文）》 2007年第1卷第2期页码 202-206 doi: 10.1007/s11783-007-0035-z

摘要： Sediment environmental capacity of pollutants is very important for marine environmental management. Based on the methodology of a study on water, soil environmental capacity, and mass conservation theory in a system, the concept and model on sediment environmental capacity for Cs in Daya Bay were developed. The static capacity for Cs in the upper sediment near the shore at a shallow area was calculated, and the annual dynamic capacity and total dynamic capacity were also calculated through determination of the typical biomass in the sediment. The results showed that the estimated environmental capacity for Cs in sediments was approximately equal to the current input of Cs into the sediments. Controlling the input of Cs in the sediments within the environmental capacity guarantees the sustainability of the current situation of the Daya Bay ecosystem and avoidance of a significant degradation of the system.

关键词： concept Sediment environmental conservation theory significant degradation ecosystem