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Facile controlled synthesis of hierarchically structured mesoporous Li4Ti5O12/C/rGO composites as high-performance

Cehuang FU, Shuiyun SHEN, Ruofei WU, Xiaohui YAN, Guofeng XIA, Junliang ZHANG

《能源前沿（英文）》 2022年第16卷第4期页码 607-612 doi: 10.1007/s11708-021-0798-0

摘要： In this paper, a facile strategy is proposed to controllably synthesize mesoporous Li₄Ti₅O₁₂/C nanocomposite embedded in graphene matrix as lithium-ion battery anode via the co-assembly of Li₄Ti₅O₁₂ (LTO) precursor, GO, and phenolic resin. The obtained composites, which consists of a LTO core, a phenolic-resin-based carbon shell, and a porous frame constructed by rGO, can be denoted as LTO/C/rGO and presents a hierarchical structure. Owing to the advantages of the hierarchical structure, including a high surface area and a high electric conductivity, the mesoporous LTO/C/rGO composite exhibits a greatly improved rate capability as the anode material in contrast to the conventional LTO electrode.

关键词： Li₄Ti₅O₁₂ phenolic-resin-based carbon mesoporous composite graphene

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Effective regeneration of thermally deactivated commercial V-W-Ti catalysts

Xuesong SHANG, Jianrong LI, Xiaowei YU, Jinsheng CHEN, Chi HE

《化学科学与工程前沿（英文）》 2012年第6卷第1期页码 38-46 doi: 10.1007/s11705-011-1167-z

摘要： An effective method for the regeneration of thermally deactivated commercial monolith SCR catalysts was investigated. Two types of regenerated solutions, namely NH Cl (1 mol/L) and dilute H SO (0.5 mol/L), were employed to treat the used catalyst. The effects of temperature and the regeneration process on the structural and textural properties of the catalysts were determined by X-ray diffraction, scanning electron microscopy, N adsorption/desorption, elemental analysis and Fourier transform infrared spectroscopy. The results suggest that the anatase phase of the used catalyst is maintained after exposure to high temperatures. Some of the catalytic activity was restored after regeneration. The catalyst regenerated by aqueous NH Cl had a higher activity than that of the catalyst treated by dilute H SO . The main reason is that the NH generated from the decomposition of NH Cl at high temperatures can be adsorbed onto the catalyst which promotes the reaction. The aggregated V O were partially re-dispersed during the regeneration process, and the intrinsic oxidation of ammonia with high concentrations of O is a factor that suppresses the catalytic activity.

关键词： V₂O₅-WO₃/TiO₂ catalysts thermal deactivation regeneration NH₄Cl dilute H₂SO₄ solution

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Fabrication and in vivo evaluation of Ti6Al4V implants with controlled porous structure and complex shape

Xiang LI, Yun LUO, Chengtao WANG, Wenguang ZHANG, Yuanchao LI

《机械工程前沿（英文）》 2012年第7卷第1期页码 66-71 doi: 10.1007/s11465-012-0302-y

摘要：

Electron beam melting process was used to fabricate porous Ti6Al4V implants. The porous structure and surface topography of the implants were characterized by scanning electron microscopy (SEM) and digital microscopy (DM). The results showed that the pore size was around 600 and the porosity approximated to 57%. There was about±50 μm of undulation on implants surfaces. Standard implants and a custom implant coupled with porous sections were designed and fabricated to validate the versatility of the electron beam melting (EBM) technique. After coated with bone-like apatite, samples with fully porous structures were implanted into cranial defects in rabbits to investigate the in vivo performance. The animals were sacrificed at 8 and 12 weeks after implantation. Bone ingrowth into porous structure was examined by histological analysis. The histological sections indicated that a large amount of new bone formation was observed in porous structure. The newly formed bone grew from the calvarial margins toward the center of the bone defect and was in close contact with implant surfaces. The results of the study showed that the EBM produced Ti6Al4V implants with well-controlled porous structure, rough surface topography and bone-like apatite layer are beneficial for bone ingrowth and apposition.

关键词： electron beam melting process implant porous structure bone ingrowth

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Dechlorination of 2,2′,4,4′,5,5′-hexachlorobiphenyl by thermal reaction with activated carbon-supported

Yifei SUN, Xin FU, Wei QIAO, Wei WANG, Tianle ZHU, Xinghua LI

《环境科学与工程前沿（英文）》 2013年第7卷第6期页码 827-832 doi: 10.1007/s11783-013-0543-y

摘要： Activated carbon (AC)-supported copper or zinc made from ion exchange resin (IRCu-C and IRZn-C) have an increased metal load of 557.3 mg?g and 502.8 mg?g compared to those prepared by the traditional method involving impregnation with AC and copper (II) citrate or zinc citrate solution (LaCu-C and LaZn-C) of 12.9 mg?g and 46.0 mg?g respectively. When applied to decompose 2,2′,4,4′,5,5′-hexachlorobiphenyl at 250 °C, IRCu-C achieved higher activity of 99.0% decomposition efficiency than LaCu-C of 84.7%, IRZn-C of 90.5% and LaZn-C of 62.7%. When the reaction temperature rose to 350 °C, all the four kinds of reactants can decompose PCB-153 with efficiency above 90%. Further, X-ray photoelectron spectroscopy characterization of IRCu-C before and after the reaction indicated transformation of 19.1% of Cu atoms into Cu , illustrating that Cu is the active ingredient or electron donor promoting the decomposition of PCB-153. The mechanism underlying this process differs from a traditional H donor. However, there is no significant change on the surface of IRZn-C before and after the reaction, suggesting that Zn acts as catalyst during the process of PCB-153 decomposition.

关键词： polychlorinated biphenyls activated carbon-supported copper or zinc dechlorination electron donor

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Li₄SiO₄-coated LiNi_0.5Mn_1.5O₄ as the high performance

Shifeng YANG, Wenfeng REN, Jian CHEN

《能源前沿（英文）》 2017年第11卷第3期页码 374-382 doi: 10.1007/s11708-017-0494-2

摘要： The preparation of Li SiO -coated LiNi Mn O materials by sintering the SiO -coated nickel-manganese oxides with lithium salts using abundant and low-cost sodium silicate as the silicon source was reported. The samples were characterized by X-ray diffraction, scanning electron microscopy and transmission electron microscopy. It was found that a uniform and complete SiO coating layer could be obtained at a suitable pH value of 10, which transformed to a good Li SiO coating layer afterwards. When used as the cathode materials for lithium-ion batteries, the Li SiO -coated LiNi Mn O samples deliver a better electrochemical performance in terms of the discharge capacity, rate capability, and cycling stability than that of the pristine material. It can still deliver 111.1 mAh/g at 20 C after 300 cycles, with a retention ratio of 93.1% of the stable capacity, which is far beyond that of the pristine material (101.3 mAh/g, 85.6%).

关键词： lithium-ion batteries cathode material LiNi_0.5Mn_1.5O₄ lithium-ion conductor coating

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行星表面动力着陆自主制导方法综述 Review

宋征宇1,5,王聪2,Stephan THEIL3,David SEELBINDER3,Marco SAGLIANO3,刘新福4,邵之江5

《信息与电子工程前沿（英文）》 2020年第21卷第5期页码 649-808 doi: 10.1631/FITEE.1900458

摘要：本文总结了天体表面精确软着陆的自主制导方法。首先回顾了动力下降制导方法的发展，重点介绍了其在约束处理和提升计算效率方面的贡献。随着对可重复使用运载器需求的不断增加，以及太空探索带来更多的科学回报，定点软着陆成为一项基本要求。不同于过去任务中公里级的着陆精度，未来行星着陆器在满足全部速度和姿态约束条件下，着陆位置精度要达到10米级，这项任务的困难引起学者对自主制导方法的兴趣。本文讨论了动力下降阶段一般性的3自由度和6自由度优化问题，并对比月球、火星和地球3种典型着陆场景的特点。在此基础上，通过比较解析制导方法、数值优化算法和基于学习的方法，详细阐述自主制导方法的特点和适应性，并讨论非凸问题的凸化处理和求解策略。随后提出自主制导方法工程应用的3个关键问题：物理可行性、模型精度和实时性。最后，简要介绍各国航天组织（包括美国、中国、法国、德国和日本）研发的垂直起降验证飞行器，以及目前在验证飞行器上开展的制导方法试验工作。

关键词：自主制导方法；定点软着陆；动力下降；非线性规划

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配位不饱和Au-O-Ti³⁺活性位点的构建及其在低温丙烯气相环氧化反应中强化氢气效率的研究 Article

宋钊宁, 闫昊, 袁俊聪, 马宏飞, 曹建琳, 王永祥, 王强, 彭冲, 邓风, 冯翔, 陈德, 杨朝合, 胡永康

《工程（英文）》 2023年第25卷第6期页码 144-156 doi: 10.1016/j.eng.2023.01.008

摘要：

自1998年以来，人们广泛认为Au/Ti基催化剂的Au-O-Ti⁴⁺位点是在相对高温条件下丙烯气相环氧化反应的活性位点，但该类催化剂的H₂有效利用率普遍较低本工作发现了一种在相对低温条件下丙烯气相环氧化反应的新活性位点Au-O-Ti³⁺。并且利用原位紫外-可见光谱（operando UV-vis）技术研究了Ti-OOH反应中间体的动态演化过程，结果表明，在Au-O-Ti³⁺活性位点上的Ti-OOH的生成速率比在Au-O-Ti⁴⁺活性位点上的明显增高。Ti³⁺位点促进了Au和Ti³⁺之间的电子转移，从而增强了催化剂对O₂的吸附能力，有效促进H₂O₂

关键词：丙烯环氧化 H₂有效利用率 Au/Ti双功能催化剂配位不饱和Ti位点密度泛函理论

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Function of Slit/Robo signaling in breast cancer

null

《医学前沿（英文）》 2015年第9卷第4期页码 431-436 doi: 10.1007/s11684-015-0416-9

摘要：

Slit and Robo are considered tumor suppressors because they are frequently inactivated in various tumor tissue. These genes are closely correlated with CpG hypermethylation in their promoters. The Slit/Robo signaling pathway is reportedly involved in breast cancer development and metastasis. Overexpression of Slit/Robo induces its tumor suppressive effects possibly by inactivating the β-catenin/LEF/TCF and PI3K/Akt signaling pathways or by altering β-catenin/E-cadherin-mediated cell-cell adhesion in breast cancer cells. Furthermore, loss of Slit proteins or their Robo receptors upregulates the CXCL12/CXCR4 signaling axis in human breast carcinoma. In addition, this pathway regulates the distant migration of breast cancer cells not only by mediating the phosphorylation of the downstream molecules of CXCL12/CXCR4 and srGAPs, such as PI3K/Src, RAFTK/ Pyk2, and CDC42, but also by regulating the activities of MAP kinases. This review includes recent studies on the functions of Slit/Robo signaling in breast cancer and its molecular mechanisms.

关键词： Slit/Robo hypermethylation β-catenin CXCL12/CXCR4 migration

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Rh₂O₃/hexagonal CePO₄ nanocatalysts for N₂O decomposition

Huan Liu, Zhen Ma

《化学科学与工程前沿（英文）》 2017年第11卷第4期页码 586-593 doi: 10.1007/s11705-017-1659-6

摘要： Hexagonal CePO nanorods were prepared by a precipitation method and hexagonal CePO nanowires were prepared by hydrothermal synthesis at 150 °C. Rh(NO ) was then used as a precursor for the impregnation of Rh O onto these CePO materials. The Rh O supported on the CePO nanowires was much more active for the catalytic decomposition of N O than the Rh O supported on CePO nanorods. The stability of both catalysts as a function of time on stream was studied and the influence of the co-feed (CO , O , H O or O /H O) on the N O decomposition was also investigated. The samples were characterized by N adsorption-desorption, inductively coupled plasma optical emission spectroscopy, X-ray diffraction, transmission electron microscopy, X-ray photoelectron microscopy, hydrogen temperature-programmed reduction, oxygen temperature-programmed desorption, and CO temperature-programmed desorption in order to correlate the physicochemical and catalytic properties.

关键词： Rh₂O₃ CePO₄ N₂O decomposition

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Phase equilibrium of the ternary system of NH 4 Cl—CaCl 2 —H 2 O at 50°C

Xia LI, Junsheng YUAN, Zhiyong JI, Jianxin CHEN,

《化学科学与工程前沿（英文）》 2010年第4卷第1期页码 75-77 doi: 10.1007/s11705-009-0296-0

摘要： The equilibrium data on the ternary system of NHCl—CaCl—HO at 50°C were investigated using the wet-residue method. The experimental results show that there are three pure phase crystal areas of NHCl, 2NHCl·CaCl·3HO and CaCl·2HO, two mixture phase crystal areas of NHCl and 2NHCl·CaCl·3HO, and 2NHCl·CaCl·3HO and CaCl·2HO in the system. A new hydration double salt (2NHCl·CaCl·3HO) was found in the ternary equilibrium system for the first time.

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UI图层合并器：基于计算机视觉与边界先验的UI图层合并方法 Research Article

陈云农1,5,甄焱鲲4,施楚宁2,李佳智2,陈柳青2,3,5,李泽健1,3,5,孙凌云2,3,5,周婷婷4,常艳芳4

《信息与电子工程前沿（英文）》 2023年第24卷第3期页码 373-387 doi: 10.1631/FITEE.2200099

摘要：随着互联网行业图形用户界面（GUI）开发工作量的快速增长，国内外学者试图从GUI图片生成可维护的前端代码。该任务更适合从包含有用户界面元数据的UI设计稿来实现代码生成。然而，碎片图层不可避免地会出现在UI设计稿中，这大大降低了生成代码的质量。目前尚未有自动化GUI技术来检测并合并碎片图层以提高生成代码的可维护性。本文提出UI图层合并器（UILM），一种基于计算机视觉的方法，可以自动检测并合并碎片图层为完整的UI组件。本文提出的UILM包含合并区域检测器和碎片图层合并算法。合并区域检测器结合边界先验知识来准确地检测出UI组件的边界。基于此，碎片图层合并算法可以搜索出边界内的相关碎片层并将其合并为整体。此外，我们提出一种动态数据增强算法来提高合并区域检测器的性能。我们还构建了用于训练合并区域检测器和测试UILM的大规模UI数据集。实验结果表明，本文提出的方法在合并区域检测方面优于最佳基线，并达到了有效的图层合并准确率。最后，对真实应用程序的用户研究也证实了本文方法的有效性。

关键词：用户界面（UI）生成代码；UI设计规范；UI碎片图层合并；目标检测

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CH₄ and N₂O emissions from double-rice cropping system as affected by Chinese milk

Heshui XU,Dengyun LI,Bo ZHU,Kai ZHANG,Yadong YANG,Chen WANG,Ying JIANG,Zhaohai ZENG

《农业科学与工程前沿（英文）》 2017年第4卷第1期页码 59-68 doi: 10.15302/J-FASE-2017137

摘要： Chinese milk vetch (CMV) and rice straw (RS) were incorporated into soil to substitute for synthetic N fertilizers and to maintain soil fertility. However, little is known about the integrated impacts of CMV and RS incorporation on CH and N O emissions in double-rice cropping systems in southern China. A field experiment was conducted to estimate the integrated impacts of CMV and RS incorporation in the early- and late-rice seasons on CH and N O emissions. All treatments received uniform N inputs, 6%–37% of which was replaced by CMV and RS crop residue. CMV and/or RS incorporation produced equivalent or slightly more grain yield, while reducing N O emissions by 3%–43%. However, both CMV and RS incorporation increased CH emissions. Annual CH emissions ranged from 321 to 614 kg·hm from CMV and RS amendment treatments, which were 1.5–2.9 times higher than that from synthetic N. Compared with single synthetic N fertilizer, incorporation of CMV and/or RS increased GWP and yield-scaled GWP by 45%–164% and 45%–153%, respectively. Our results demonstrate CMV and RS amendments replacing N fertilizer, maintained stable yield, mitigated N O emission, but enhanced CH emission. Further study is needed on crop residue management in double-cropping rice systems.

关键词： Chinese milk vetch CH₄ double-rice cropping system grain yield N₂O rice straw

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NiCo2O4@quinone-rich N–C core–shell nanowires as composite electrode for electric double layer capacitor

《化学科学与工程前沿（英文）》 2023年第17卷第4期页码 373-386 doi: 10.1007/s11705-022-2223-6

摘要： The bind-free carbon cloth-supported electrodes hold the promises for high-performance electrochemical capacitors with high specific capacitance and good cyclic stability. Considering the close connection between their performance and the amount of carbon material loaded on the electrodes, in this work, NiCo₂O₄ nanowires were firstly grown on the substrate of active carbon cloth to provide the necessary surface area in the longitudinal direction. Then, the quinone-rich nitrogen-doped carbon shell structure was formed around NiCo₂O₄ nanowires, and the obtained composite was used as electrode for electric double layer capacitor. The results showed that the composite electrode displayed an area-specific capacitance of 1794 mF∙cm^–2 at the current density of 1 mA∙cm^–2. The assembled symmetric electric double layer capacitor achieved a high energy density of 6.55 mW∙h∙cm^–3 at a power density of 180 mW∙cm^–3. The assembled symmetric capacitor exhibited a capacitance retention of 88.96% after 10000 charge/discharge cycles at the current density of 20 mA∙cm^–2. These results indicated the potentials in the preparation of the carbon electrode materials with high energy density and good cycling stability.

关键词： carbon cloth NiCo₂O₄ nanowires core−shell structure quinone-rich electric double layer capacitor

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Synthesis of MnFe

Jian LI,Yue JIAO,Caichao WAN

《农业科学与工程前沿（英文）》 2017年第4卷第1期页码 116-120 doi: 10.15302/J-FASE-2017141

摘要： Cellulose aerogel, with abundant three-dimensional architecture, has been considered as a class of ideal eco-friendly matrix materials to encapsulate various nanoparticles for synthesis of miscellaneous functional materials. In the present paper, hexagonal single-crystalline MnFe O was fabricated and inserted into the cellulose aerogel using an chemical precipitation method. The as-prepared MnFe O nanoparticles were well dispersed and immobilized in the micro/nanoscale pore structure of the aerogel, and exhibited superparamagnetic behavior. In addition, the nanocomposite was easily actuated under the effect of an external magnetic field, revealing its strong magnetic responsiveness. Combined with the advantages of environmental benefits, facile synthesis method, strong magnetic responsiveness, and unique structural feature, this class of MnFe O /cellulose aerogel nanocomposite has possible uses for applications such as magnetically actuated adsorbents.

关键词： cellulose aerogel MnFe₂O₄ magnetic responsiveness nanocomposite

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Alkylation of benzene with carbon dioxide to low-carbon aromatic hydrocarbons over bifunctional Zn-Ti/HZSM-5 catalyst

Xiangyu Liu, Yanling Pan, Peng Zhang, Yilin Wang, Guohao Xu, Zhaojie Su, Xuedong Zhu, Fan Yang

《化学科学与工程前沿（英文）》 2022年第16卷第3期页码 384-396 doi: 10.1007/s11705-021-2045-y

摘要： Alkylation of benzene to value-added, high octane number and low toxic toluene and xylenes provides a way to lower benzene content in gasoline pool, and is hence a method to promote fuel quality. On the other hand, CO accumulation in the atmosphere causes global warming and requires effective route for its valorization. Utilization of CO as a carbon source for benzene alkylation could achieve both goals. Herein, alkylation of benzene with CO and H was realized by a series of low-cost bifunctional catalysts containing zinc/titanium oxides (Zn/Ti oxides) and HZSM-5 molecular sieves in a fixed-bed reactor. By regulating and controlling oxygen vacancies of Zn/Ti oxides and the acidities of HZSM-5, benzene conversion and CO conversion reached 28.7% and 29.9% respectively, along with a total selectivity of toluene and xylene higher than 90%. In this process, more than 25% CO was effectively utilized and incorporated into the target products. Moreover, the mechanism of the reaction was analyzed and the course was simultaneously traced. CO was transformed into methanol firstly, and then methanol reacted with benzene generating toluene and xylene. The innovation provides a new method for upgrading of fuels and upcycling the emissions of CO , which is of great environmental and economic benefits.

关键词： carbon dioxide benzene alkylation bifunctional catalyst mechanism