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1Synthesis, properties, and applications of graphene oxide/reduced graphene oxide and their nanocomposites显示文摘Thanks to their remarkable mechanical, electrical, thermal, and barrier properties, graphene-based nanocomposites have been a hot area of research in the past decade. Because of their simple top-down synthesis, graphene oxide (GO) and reduced graphene oxide (rGO) have opened new possibilities for gas barrier, membrane separation, and stimuli-response characteristics in nanocomposites. Herein, we review the synthesis techniques most commonly used to produce these graphene derivatives, discuss how synthesis affects their key material properties, and highlight some examples of nanocomposites with unique and impressive properties. We specifically highlight their performances in separation applications, stimuli-responsive materials, anti-corrosion coatings, and energy storage. Finally, we discuss the outlook and remaining challenges in the field of practical industrial-scale production and use of graphene-derivative-based polymer nanocomposites.Andrew T. Smith Anna Marie LaChance Songshan Zeng Bin Liu Luyi Sun 2019Nano Materials Science2019,1,1:33
2Review on photocatalytic and electrocatalytic artificial nitrogen fixation for ammonia synthesis at mild conditions: Advances,challenges and perspectives显示文摘The ammonia synthesis from nitrogen and water under ambient conditions is one of the most inviting but challenging reaction routes.Although nitrogen is abundant in the atmosphere and the ammonia synthesis reaction is exothermic on the thermodynamics,the conversion of N2 to ammonia is actually hard to proceed owing to the chemical inertness and stability of N2 molecules.In industry,ammonia synthesis is carried out by the Haber-Bosch process under harsh conditions (300-500 ℃,20-30 MPa) associated with the requirement of substantial energy input and the enormous emission of greenhouse gases (e.g.,CO2).Recently,a growing number of studies on photo(electro)catalytic and electrocatalytic nitrogen reduction reaction (NRR) in aqueous solution have attracted extensive attention,which holds great promise for nitrogen fixation under room temperature and atmospheric pressure.However,the very low efficiency and ambiguous mechanism still remain as the major hurdles for the development of photochemical and electrochemical NRR systems.Here we provide an overview of the latest progresses,remaining challenges and future prospects in photocatalytic and electrocatalytic nitrogen fixation.Moreover,this review offers a helpful guidance for the reasonable design of photocatalysts and electrocatalysts towards NRR by combining theory predictions and experiment results.We hope this review can stimulate more research interests in the relatively understudied but highly promising research field of NRR.Xiaolan Xue Renpeng Chen Changzeng Yan Peiyang Zhao Yi Hu Wenjun Zhang Songyuan Yang Zhong Jin 2019Nano Research2019,12,6:20
3In-situ synthesis of nanoparticles via supersolubilizing micelle self-assembly显示文摘In-situ synthesis of nano-particles using the self-assembly of molten salt and super soluble micellae was proposed based on a phenomenon of super solubilization of molten salt in reverse micellae and its self-assembly when the concentration reached up to 95%(w/w).The mechanism of the self-assembly indicates that the self-assembly of molten salt occurs in a reverse micelle where a homogenous phase is established between 5%(w/w)of a surfactant with a VB value of less than 1 and a hydrocarbon spe- cies.This synthesis has some unique features,such as being free of water,highly effective deposition and narrow distribution of particle size.WANG DingCong Fushun Research Institute of Petroleum&Petrochemicals,China Petroleum&Chemical Corporation(SINOPEC),Fushun 113001, China(email:wangdingcong@hotmail.com) 2007Science China Chemistry2007,50,1:19
4Visible light-driven organic photochemical synthesis in China显示文摘In recent years, visible light-driven organic photochemical synthesis has attracted wide research interest from academic and industrial communities due to its features of green and sustainable chemistry. In this flourishing area, Chinese chemists have devoted great efforts to different aspects of synthetic chemistry. This review will summarize their representative work according to the following categories: C–H functionalization, synthesis of aromatic aza-heterocycles, asymmetric organic photochemical synthesis, transformations of small molecules and biomolecule-compatible reactions.Yiyun Chen Liang-Qiu Lu Da-Gang Yu Cheng-Jian Zhu Wen-Jing Xiao 2019Science China Chemistry2019,62,1:19
5密码子优化的重组黄曲霉毒素解毒酶(rADTZ)在毕氏酵母中组成型分泌表达的研究显示文摘黄曲霉毒素解毒酶(ADTZ)来源于真菌Armillariella tabescens,它能够有效地分解黄曲霉毒素。为了使重组蛋白rADTZ能在毕氏酵母中高效分泌表达,根据毕氏酵母密码子的偏好性对rADTZ的5末端的编码区域进行了优化,利用two-step DNA synthsis技术合成出ADTZ优化的基因序列OPT-ADTZ,并与组成型表达载体pGAPZaA连接,构建重组质粒pNOA,线性化pNOA后转化至毕氏酵母GS115中,实现了密码子优化的rADTZ组成型分泌表达。左振宇 刘大岭 胡亚冬 胡熔 姚冬生 2007中国农业科技导报2007,9,5:18
6Dimensional synthesis of a 3-DOF parallel manipulator based on dimensionally homogeneous Jacobian matrix显示文摘A study of dimensional synthesis of a 3-DOF parallel manipulator with coupling of translation and rotation is carried out.The architecture of the manipulator is composed of a moving platform attached to a fixed base through three identical PRS(prismatic-revolute-spherical) serial limbs,whose unique topology leads to the physical unit inconsistency of the conventional Jacobian matrix and the emergence of the parasitic motion.Then this paper introduces a kinetostatic performance index of the manipulator based on the condition of a dimensionally homogeneous Jacobian matrix,later,the workspace of the aforementioned manipulator is searched and the influence of the crucial design variables on the workspace is analyzed.Finally,a dimensional synthesis method of the manipulator is proposed,which may be regarded as a nonlinear programming problem with subject to the parasitic motion and other several engineering constraints.SUN Tao1,SONG YiMin1,LI YongGang2 & LIU LinShan1 1 School of Mechanical Engineering,Tianjin University,Tianjin 300072,China 2 School of Mechanical Engineering,Tianjin University of Technology and Education,Tianjin 300222,China 2010Science China(Technological Sciences)2010,53,1:17
7Hydrogen and syngas production from two-step steam reforming of methane over CeO_2-Fe_2O_3 oxygen carrier显示文摘Two-step steam reforming of methane (SRM) is a novel chemical looping process towards the production of pure hydrogen and syngas (synthesis gas), consisting of a syngas production step and a water-splitting step. Renewable energy can be used to drive this process for hydrogen production, especially solar energy. CeO2-Fe2O3 complex oxide oxygen carrier was prepared by the impregnation method and characterized by means of X-ray diffractometer (XRD), Raman spectroscopy (Raman) and hydrogen programmed reduction (H2-TPR). CH4 temperature programmed and isothermal reactions were adopted to test syngas production reactivity, and water splitting reaction was employed to investigate water-splitting activity. Moreover, two-step SRM performance was evaluated by a successive redox cycle. The results showed that CO-uncontaminated H2 and highly selective syngas (with H2/CO ratio close to 2) could be respectively obtained from two steps, and CeFeO3 formation was found in the first redox cycle and proved to be enhanced by the redox treatment. After 10 successive cycles, obvious CeFeO3 phase was detected, which may be responsible for favorable successive redox cycle performances.祝星 王华 魏永刚 李孔斋 程显名 2010Journal of Rare Earths2010,28,6:15
8RELIABILITY-BASED ANALYSIS AND SYNTHESIS OF MECHANICAL ERROR FOR PATH GENERATING LINKAGES显示文摘RELIABILITY-BASEDANALYSISANDSYNTHESISOFMECHANICALERRORFORPATHGENERATINGLINKAGESShiZhongxiu,LiFengqiangQingdaoUniversityAbstra...Shi Zhongxiu ,Li FengqiangQingdao University 1997Chinese Journal of Mechanical Engineering1997,10,2:15
9CATALYSTS FOR SYNTHESIS OF N-VINYLPYRROLIDONE显示文摘崔英德 易国斌 廖列文 康正 2000化工学报2000,51,4:15
10Single-atom catalyst: a rising star for green synthesis of fine chemicals显示文摘The green synthesis of fine chemicals calls for a new generation of efficient and robust catalysts. Single-atom catalysts(SACs), in which all metal species are atomically dispersed on a solid support, and which often consist of well-defined mononuclear active sites, are expected to bridge homogeneous and heterogeneous catalysts for liquid-phase organic transformations. This review summarizes major advances in the SAC-catalysed green synthesis of fine chemicals in the past several years, with a focus on the catalytic activity, selectivity and reusability of SACs in various organic reactions. The relationship between catalytic performance and the active site structure is discussed in terms of the valence state, coordination environment and anchoring chemistry of single atoms to the support, in an effort to guide the rational design of SACs in this special area, which has traditionally been dominated by homogeneous catalysis.Finally, the challenges remaining in this research area are discussed and possible future research directions are proposed.Leilei Zhang Yujing Ren Wengang Liu Aiqin Wang Tao Zhang 2018National Science Review2018,5,5:15
11Malus sieversii: the origin, flavonoid synthesis mechanism, and breeding of red-skinned and red-fleshed apples显示文摘Flavonoids play essential roles in human health.Apple(Malus domestica Borkh.),one of the most widely produced and economically important fruit crops in temperate regions,is a significant source of flavonoids in the human diet and is among the top nutritionally rated and most widely consumed fruits worldwide.Epidemiological studies have shown that the consumption of apples,which are rich in a variety of free and easily absorbable flavonoids,is associated with a decreased risk of various diseases.However,apple production is challenged by serious inbreeding problems.The narrowing of the hereditary base has resulted in apples with poor nutritional quality and low flavonoid contents.Recently,there have been advances in our understanding of the roles that Malus sieversii(Ledeb.)M.Roem has played in the process of apple domestication and breeding.In this study,we review the origin of cultivated apples and red-fleshed apples,and discuss the genetic diversity and construction of the core collections of M.sieversii.We also discuss current research progress and breeding programs on red-skinned and red-fleshed apples and summarize the exploitation and utilization of M.sieversii in the breeding of high-flavonoid,and red-fleshed apples.This study highlights a valuable pattern of horticultural crop breeding using wild germplasm resources.The future challenges and directions of research on the molecular mechanisms of flavonoid accumulation and high-flavonoid apple breeding are discussed.Nan Wang Shenghui Jiang Zongying Zhang Hongcheng Fang Haifeng Xu Yicheng Wang Xuesen Chen 2018Horticulture Research2018,5,1:15
12Chromosome-scale genome assembly provides insights into the evolution and flavor synthesis of passion fruit (Passiflora edulis Sims)显示文摘Passion fruit(Passiflora edulis Sims)is an economically valuable fruit that is cultivated in tropical and subtropical regions of the world.Here,we report an~1341.7Mb chromosome-scale genome assembly of passion fruit,with 98.91%(~1327.18Mb)of the assembly assigned to nine pseudochromosomes.The genome includes 23,171 protein-coding genes,and most of the assembled sequences are repetitive sequences,with long-terminal repeats(LTRs)being the most abundant.Phylogenetic analysis revealed that passion fruit diverged after Brassicaceae and before Euphorbiaceae.Ks analysis showed that two whole-genome duplication events occurred in passion fruit at 65 MYA and 12 MYA,which may have contributed to its large genome size.An integrated analysis of genomic,transcriptomic,and metabolomic data showed that‘alpha-linolenic acid metabolism’,‘metabolic pathways’,and‘secondary metabolic pathways’were the main pathways involved in the synthesis of important volatile organic compounds(VOCs)in passion fruit,and this analysis identified some candidate genes,including GDP-fucose Transporter 1-like,Tetratricopeptide repeat protein 33,protein NETWORKED 4B isoform X1,and Golgin Subfamily A member 6-like protein 22.In addition,we identified 13 important gene families in fatty acid pathways and eight important gene families in terpene pathways.Gene family analysis showed that the ACX,ADH,ALDH,and HPL gene families,especially ACX13/14/15/20,ADH13/26/33,ALDH1/4/21,and HPL4/6,were the key genes for ester synthesis,while the TPS gene family,especially PeTPS2/3/4/24,was the key gene family for terpene synthesis.This work provides insights into genome evolution and flavor trait biology and offers valuable resources for the improved cultivation of passion fruit.Zhiqiang Xia Dongmei Huang Shengkui Zhang Wenquan Wang Funing Ma Bin Wu Yi Xu Bingqiang Xu Di Chen Meiling Zou Huanyu Xu Xincheng Zhou Rulin Zhan Shun Song 2021Horticulture Research2021,8,1:15
13Rare earth upconversion nanophosphors: synthesis, functionalization and application as biolabels and energy transfer donors显示文摘This review focused on rare earth upconversion nanophosphors (UCNPs), a particular class of emitters whose photoluminescence mechanism is of fundamental difference from that of conventional dyes and semiconductor quantum dots. We in the first section gave a brief summary on a variety of synthetic methodologies developed during the past decades. Instead of presenting an exhaustive reference list, we selected only a few representative examples, illustrating the merits and limits of each involved synthetic route. Then we surveyed the recent progress in the functionalization techniques for these nanomaterials, depicting the modification in microstructures and improvement in properties with respect to the parent nanoparticles. And finally, we emphasized their application in the research fields of biolabeling and energy transfer, narrating their superior performance benefiting from the unique excitation and emission properties.张超 孙聆东 张亚文 严纯华 2010Journal of Rare Earths2010,28,6:14
14Review and prospect of NiCo_(2)O_(4)-based composite materials for supercapacitor electrodes显示文摘Supercapacitors known as typical electrochemical capacitors have been considered as one of the most promising candidates of energy storage systems owing to their advantages such as high-power density,long life span and lower production cost.The electrode materials play a crucial role on properties of supercapacitors.Hence,many researches have been focused on the development of novel electrode materials for high-performance supercapacitors.NiCo_2O_4as supercapacitor electrode material has drawn more and more attentions in recent years due to its outstanding advantages,such as high theoretical capacity,low cost,natural abundance and easy of synthesis.However,the NiCo_2O_4always suffer from severe capacity deterioration because of the low electrical conductivity and small surface area.Hence,it is necessary to systematically and comprehensively summarize the progress in understanding and modifying NiCo_2O_4-based materials from various aspects.In this review,the structure and synthesis method of NiCo_2O_4-based materials are discussed in detail.And then,the major goal of this review is to highlight new progress in using proposed strategies to improve the cycling stability and rate capacity of NiCo_2O_4-based materials,including synthesis,control of special morphologies and design of composite materials.Finally,an insight into the future research and development of Ni Co_2O_4-based materials for supercapacitors is prospected.Yanmei Li Xiao Han Tingfeng Yi Yanbing He Xifei Li 2019Journal of Energy Chemistry2019,28,4:14
15Virtual screening of inorganic materials synthesis parameters with deep learning显示文摘Virtual materials screening approaches have proliferated in the past decade,driven by rapid advances in first-principles computational techniques,and machine-learning algorithms.By comparison,computationally driven materials synthesis screening is still in its infancy,and is mired by the challenges of data sparsity and data scarcity:Synthesis routes exist in a sparse,highdimensional parameter space that is difficult to optimize over directly,and,for some materials of interest,only scarce volumes of literature-reported syntheses are available.In this article,we present a framework for suggesting quantitative synthesis parameters and potential driving factors for synthesis outcomes.We use a variational autoencoder to compress sparse synthesis representations into a lower dimensional space,which is found to improve the performance of machine-learning tasks.To realize this screening framework even in cases where there are few literature data,we devise a novel data augmentation methodology that incorporates literature synthesis data from related materials systems.We apply this variational autoencoder framework to generate potential SrTiO_(3) synthesis parameter sets,propose driving factors for brookite TiO_(2) formation,and identify correlations between alkali-ion intercalation and MnO_(2) polymorph selection.Edward Kim Kevin Huang Stefanie Jegelka Elsa Olivetti 2017npj Computational Materials2017,,1:14
16The modification of natural products for medical use显示文摘Drug innovation is characterized by painstaking molecular-level syntheses and modifications as the basic components of research and development.Similarly,natural products are chemically tailored and modified based upon their structural and biological properties.To some extent,the modification of natural products is quite different from de novo structure-based drug discovery.This review describes the general strategies and principles for the modification of natural products to drugs,as illustrated by several successful medicines that originated from natural products.Zongru Guo 2017Acta Pharmaceutica Sinica B2017,7,2:14
17Recent progress towards mild-condition ammonia synthesis显示文摘Ammonia is essential for food and energy.Industrial ammonia synthesis via Haber–Bosch process is energy-intensive and releases large amount of CO2.Increasing research efforts are devoted to 'green'ammonia synthesis.The present article reviews the recent progress in the fields of thermocatalytic, electrocatalytic, photocatalytic and chemical looping processes for dinitrogen reduction towards ammonia formation and discusses the challenges borne for mild-condition synthesis.Qianru Wang Jianping Guo Ping Chen 2019Journal of Energy Chemistry2019,28,9:13
18Modified activated carbon with interconnected fibrils of iron-oxyhydroxides using Mn^(2+) as morphology regulator, for a superior arsenic removal from water显示文摘The arsenic removal efficiency of iron-modified activated carbons depends greatly on the number of available iron oxide surface sites, which are given by the surface area of the anchored particles. In this sense, aiming the generation of an adsorbent with superior arsenic adsorption capacity, we developed a protocol to anchor interconnected fibrils of iron oxyhydroxides, using Mn^(2+) as a morphology regulator. The protocol was based on a microwave-assisted hydrothermal method, using bituminous based activated carbon and both Fe^(2+) and Mn^(2+) ions in the hydrolysis solution. The elemental analysis of modified carbons revealed that Mn does not anchor to the carbon. However, when Mn is included in the hydrolysis solution, the iron content in the activated carbon increased up to 3.5 wt%,without considerable decreasing the adsorbent surface area. Under specific hydrothermal conditions, the Mn^(2+) promoted the formation of iron oxide nanoparticles shaped as interconnected fibrils. This material showed a superior arsenic adsorption capacity in comparison to similar iron modified activated carbons(5 mg As/g carbon, at 2 mg As/L),attributed to the increase in quantity and availability of active sites located on the novel interconnected fibrils of iron oxyhydroxides nanostructures.Cesar Nieto-Delgado Joel Gutiérrez-Martínez J.Rene Rangel-Méndez 2019Journal of Environmental Sciences2019,31,2:12
19高强度聚乳酸骨折内固定棒的研制显示文摘High molecular weight up to 80×10 4 of poly(L lactide)(PLLA) was synthesized by bulk polymerization of L lactide using stannous octoate as initiator. The influence of polymerization time, temperature and initiator concentration on the molecular weight of PLLA was studied. An enhancement technique named fibrillated compression moulding has been developed for preparing high strength PLLA rods with bending strength of 20 260 MPa and shear strength of 170 190 MPa respectivity.卢泽俭 廖凯荣 罗丙红 赵剑豪 1999生物医学工程学杂志1999,16,S1:12
20Facile Fabrication of Hierarchically Porous Carbonaceous Monoliths with Ordered Mesostructure via an Organic Organic Self-Assembly显示文摘A simple strategy for the synthesis of macro-mesoporous carbonaceous monolith materials has been demonstrated through an organic organic self-assembly at the interface of an organic scaffold such as polyurethane(PU)foam.Hierarchically porous carbonaceous monoliths with cubic(Im m)or hexagonal(p6mm)mesostructure were prepared through evaporation induced self-assembly of the mesostructure on the three-dimensional(3-D)interconnecting struts of the PU foam scaffold.The preparation was carried out by using phenol/formaldehyde resol as a carbon precursor,triblock copolymer F127 as a template for the mesostructure and PU foam as a sacrificial monolithic scaffold.Their hierarchical pore system was macroscopically fabricated with cable-like mesostructured carbonaceous struts.The carbonaceous monoliths exhibit macropores of diameter 100450μm,adjustable uniform mesopores(3.87.5 nm),high surface areas(200870 m2/g),and large pore volumes(0.170.58)cm3/g.Compared with the corresponding evaporation induced self-assembly(EISA)process on a planar substrate,this facile process is a time-saving,labor-saving,space-saving,and highly effi cient pathway for mass production of ordered mesoporous materials.Chunfeng Xue Bo Tu Dongyuan Zhao 2009Nano Research2009,2,3:12
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