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Nano Research 2023年第7期16卷 10652-10659页

作者： Xinli Shi Yucong Zu Xilin Li Tongyi Zhao Hao Ren Fuxing Sun State Key Laboratory of Inorganic Synthesis and Preparative Chemistry Jilin UniversityChangchun 130012China

Metal-organic frameworks(MOFs)with HKUST-like tbo structures have been paid specific attention for gas sorption and separation because of their specific pore features.According to the geometric similarity of spirobifluorene and[Cu_(2)(O_(2)CR)_(4)]paddlewheel secondary building units(Cu_(2)SBUs)in HKUST-1,we attempted to rationally construct a HKUST-like MOF by a Substitution strategy.Using a judiciously designed octatopic carboxylate ligand,a copper-organic framework,JUC-220,was synthesized.The crystals of JUC-220 exhibited characteristic features in cubic with disorder,possibly due to the disorder Substitution and high symmetry of tbo topology.Two related HKUST-like structure models were considered.Thanks to the suitable pore size and specific pore shapes,the adsorption selectivities of JUC-220 for C_(3)H_(8)/CH_(4)(5/85)and C_(2)H_(6)/CH_(4)(10/85)gas mixtures were as high as 736 and 46 respectively at 298 K and 1 bar.Specially,JUC-220 exhibited excellent trace adsorption performance of C_(3)H_(8)and C_(2)H_(6)as well as reverse adsorption behavior of C_(2)H_(6)/C_(2)H_(4).Thus,JUC-220 serves as an example of HKUST-like MOF with disorder for light hydrocarbons separation and the implementation of Substitution which can be used to explore more porous MOFs.

关键词： HKUST-like metal-organic frameworks(MOFs) reticular chemistry disorder Substitution trace adsorption light hydrocarbons separation

Impact of inter-fuel Substitution on energy intensity in Ghana

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Frontiers in Energy 2020年第1期14卷 27-41页

作者： Boqiang LIN Hermas ABUDU School of Management China Institute for Studies in Energy PolicyCollaborative Innovation Center for Energy Economics and Energy PolicyXiamen UniversityXiamen361005China Belt and Road Research Institute Xiamen UniversityXiamen361005China

Energy intensity and elasticity,together with inter-fuel Substitution are key issues in the current development stage of Ghana.Translog production and ridge regression are applied for studying these issues with a data range of 2000–2015.The current energy dynamics reveal the expected inverse relationship:higher energy intensity and lower elasticity with economic growth.There are evidences of energy-economic challenges:high energy cost,inefficiency and backfire rebound effect.The implications are higher energy losses in the system,more consumption of lower-quality energy together with low energy technology innovation.Energy is wasted and directly not productive with economic activities.It is observed further that the higher energy intensity invariably increases CO2 emission because approximately 95%of total energy is derived from hydrocarbons and biomass.An inter-fuel Substitution future scenario design was further conducted and the results were positive with growth,lower energy intensity,and improved energy efficiency.Therefore,government and energy policymakers should improve energy efficiency,cost,and productiveness.That is,they should change energy compositions and augment energy technology innovation,thus,increasing renewable share to 15%by 2026,reducing wood and charcoal by about 69%,and increasing natural gas to about 776%.Energy policymakers should enhance the installation of smart energy,cloud energy solution,tokenization of energy system and storage.

关键词： energy intensity energy elasticity inter-fuel Substitution prospects energy contribution Translog production approach ridge regression

Tuning effect of silicon Substitution on magnetic and high frequency electromagnetic properties of R2Fe17 and their composites

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Journal of Rare Earths 2019年第10期37卷 1102-1107页

作者： Wenyun Yang Qiwei Hu Guanyi Qiao Liang Zha Shunquan Liu Jingzhi Han Honglin Du Yan Zhang Yingchang Yang Changsheng Wang State Key Laboratory for Mesoscopic Physics School of PhysicsPeking UniversityBeijing100871China Beijing Key Laboratory for Magnetoeletric Materials and Devices Beijing100871China

In this work, we report the tuning effect of the Si Substitution on the magnetic and high frequency electromagnetic properties of R2 Fe17 compounds and their paraffin composites. It is found that the introduction of Si can remarkably improve the magnetic and electromagnetic properties of the R2 Fe17 compounds, making the R2 Fe17 exSix-paraffin composites excellent microwave absorption materials(MAMs). By introducing the Si element, their saturation magnetizations decrease slightly, while much higher Curie temperatures are obtained. Furthermore, better impedance match is reached due to the decrease of the high-frequency permittivity ε’ by about 40%e50%, which finally enhances the performance of the microwave absorption. The peak frequency(fRL) of the reflection loss(RL) curve moves toward high frequency domain and the qualified bandwidth(QB, RL≤-10 dB) increases remarkably. The maximum QB of 3.3 GHz(12.0 e15.3 GHz) is obtained for the Sm1.5 Y0.5 Fe15 Si2-paraffin composite(d = 1.0 mm) and the maximum RL of -53.6 dB is achieved for Nd2 Fe15 Si2-paraffin composite(d = 2.2 mm), both surpassing most of the reported MAMs. Additionally, a distinguished dielectric microwave absorption peak is observed, which further increases the QB in these composites.

关键词： Rare-earth transition-metal intermetallics Si Substitution Magnetism Composites Microwave absorption properties

CH4 Gas Extraction by CO2: Substitution in Clathrate Hydrate through Bimolecular Iteration

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Chinese Physics Letters 2020年第4期37卷 140-144页

作者：于晓辉刘源杜三亚郑旭朱金龙徐洪武张建中都时禹曾晓成 J.S.Francisco 靳常青赵予生李晖 National Lab for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190 LANSCE Division Los Alamos National LaboratoryLos AlamosNew Mexico 87545USA Beijing Advanced Innovation Center for Soft Matter Science and Engineering Beijing University of Chemical TechnologyBeijing 100029 Department of Chemistry University of Nebraska-LincolnLincolnNebraska 68588USA Department of Physics Southern University of Science and Technology(SUSTech)Shenzhen 518055 Center for High Pressure Science and Technology Advanced Research(HPSTAR) Beijing 100094 Engineering Laboratory of Specialty Fibers and Nuclear Energy Materials Ningbo Institute of Industrial TechnologyChinese Academy of SciencesNingbo 315201

Methane clathrate hydrate(MCH)is a promising energy resource,but controllable extraction of CH4 from MCH remains a challenge.Gradually replacing CH4 in MCH with CO2 is an attractive scheme,as it is cost efficient and mitigates the environmentally harmful effects of CO2 by sequestration.However,the practicable implementation of this method has not yet been achieved.In this study,using in situ neutron diffraction,we confirm that CH4 in the 51262 cages of bulk structure-I(si)MCH can be substituted by gaseous CO2 under high pressure and low temperature with a high Substitution ratio(~44%)while conserving the structure of the hydrate framework.First-principles calculations indicate that CO2 binds more strongly to the 51262 cages than methane does,and that the diffusion barrier for CH4 is significantly lowered by an intermediate state in which one hydrate cage is doubly occupied by CH4 and CO2.Therefore,exchange of CO2 for CH4 in MCH is not only energetically favorable but also kinetically feasible.Experimental and theoretical studies of CH4/CO2 Substitution elucidate a method to harness energy from these combustible ice resources.

关键词： Substitution substituted attractive

Programmed sequential cutting endows Cas9 versatile base Substitution capability in plants

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Science China(Life Sciences) 2021年第6期64卷 1025-1028页

作者： Wei Yang Wei Qi Yucai Li Jiyao Wang Yanmin Luo Dehui Ding Sudong Mo Bo Chen Yu Lu Huarong Li Linjian Jiang Key Laboratory of Pest Monitoring and Green Management Ministry of Agriculture and Rural AffairsDepartment of Plant PathologyCollege of Plant ProtectionChina Agricultural UniversityBeijing 100193China Qingdao Kingagroot Compounds Co.Ltd. Qingdao 266426China

Dear Editors,CRISPR/Cas9-mediated genome editing techniques have triggered a revolution in biology research(Jinek et al.,2012).Cas9 coupled with guide RNAs cuts DNA at precise positions,and the resulting double stranded breaks(DSB)were effectively repaired by non-homologous end joining(NHEJ)pathway in higher eukaryotic cells,including animals and plants.

关键词： Substitution versatile base

Wood Substitution potential in greenhouse gas emission reduction–review on current state and application of displacement factors

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Forest Ecosystems 2021年第3期8卷 548-565页

作者： Tanja Myllyviita Sampo Soimakallio Jáchym Judl Jyri Seppälä Finnish Environment Institute Helsinki Finland

Background:Replacing non-renewable materials and energy with wood offers a potential strategy to mitigate climate change if the net emissions of ecosystem and technosystem are reduced in a considered time period.Displacement factors(DFs)describe an emission reduction for a wood-based product or fuel which is used in place of a non-wood alternative.The aims of this review were to map and assess DFs from scientific literature and to provide findings on how to harmonise practices behind them and to support coherent application.Results:Most of the reviewed DFs were positive,implying decreasing fossil GHG emissions in the technosystem.The vast majority of the reviewed DFs describe avoided fossil emissions either both in processing and use of wood or only in the latter when wood processing emissions were considered separately.Some of the reviewed DFs included emissions avoided in post-use of harvested wood products(HWPs).Changes in forest and product carbon stocks were not included in DFs except in a few single cases.However,in most of the reviewed studies they were considered separately in a consistent way along with DFs.DFs for wood energy,construction and material Substitution were widely available,whereas DFs for packaging products,chemicals and textiles were scarce.More than half of DFs were calculated by the authors of the reviewed articles while the rest of them were adopted from other articles.Conclusions:Most of the reviewed DFs describe the avoided fossil GHG emissions.These DFs may provide insights on the wood-based products with a potential to replace emissions intensive alternatives but they do not reveal the actual climate change mitigation effects of wood use.The way DFs should be applied and interpreted depends on what has been included in them.If the aim of DFs is to describe the overall climate effects of wood use,DFs should include all the relevant GHG flows,including changes in forest and HWP carbon stock and post-use of HWPs,however,based on this literature review this is not a common practice.DFs

关键词： Substitution potential replace

Effect of dysprosium Substitution on magnetic and structural properties of NiFe2O4 nanoparticles

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Journal of Rare Earths 2019年第8期37卷 871-878,I0004页

作者： MAAlmessiere YSlimani SGüner ABaykal IErcan Department of Physics College of ScienceImam Abdulrahman Bin Faisal UniversityP.O.Box 198231441 DammamSaudi Arabia Department of Nano-Medicine Research Institute for Research&Medical Consultations(IRMC)Imam Abdulrahman Bin Faisal UniversityP.O.Box 198231441 DammamSaudi Arabia Department of Biophysics Institute for Research&Medical Consultations(1RMC)Imam Abdulrahman Bin Faisal UniversityP.O.Box 198231441 DammamSaudi Arabia Institute of Inorganic Chemistry RWTH Aachen UniversityD-52074 AachenGermany

This work investigated the effect of dysprosium(Dy)ions on the structural,microstructural and magnetic properties of nickel nanospinelferrite,NiFe2 O4.The nanoparticles(NPs)of NiDyxFe(2-x)O4(0.0≤x≤0.1)were prepared via the hydrothermal method.The formation of cubic phase of Ni nanoferrite was confirmed through X-ray diffraction,field emission scanning and transmission electron microscopy.Moreover,the magnetic properties of NiDyxFe(2-x)P4(0.01≤x≤0.10)NPs were discussed.The magnetization versus field,M(H)curves exhibit super paramagnetic nature at room temperature and ferrimagnetic nature at low temperature(10 K).A noticeable improvement in the different deduced magnetic parameters is obtained especially for the NiDy(0.07)Fe(1.93)O4(x=0.07)product.The obtained result is mostly derived from the Substitution of Fe^3+ions of smaller ionic radii with Dy^3+ions of larger ionic radii that will strengthen the super exchange interactions among nanoparticles.The calculated squareness ratios are found to be much less than 0.5,due to the effect of spin disorder in the surface regions of NiDyxFe(2-x)O4(0.01≤x≤0.10)NPs.The Dy^3+ions Substitution increases the magnetic hardness(higher values of remanence Mr,coercivity Hc,and magnetic moment nB)of nickel nanoferrite samples.

关键词： NiFe2O4 Dy Substitution Structure Magnetic properties Super exchange interactions Rare earths

Identification of long-grain chromosome segment Substitution line Z744 and QTL analysis for agronomic traits in rice

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Journal of Integrative Agriculture 2020年第5期19卷 1163-1169页

作者： MA Fu-ying DU Jie WANG Da-chuan WANG Hui ZHAO Bing-bing HE Guang-hua YANG Zheng-lin ZHANG Ting WU Ren-hong ZHAO Fang-ming Rice Research Institute Academy of Agricultural SciencesSouthwest UniversityChongqing 400715P.R.China

Length of grain affects the appearance, quality, and yield of rice. A rice long-grain chromosome segment Substitution line Z744, with Nipponbare as the recipient parent and Xihui 18 as the donor parent, was identified. Z744 contains a total of six Substitution segments distributed on chromosomes(Chrs.) 1, 2, 6, 7, and 12, with an average Substitution length of 2.72 Mb. The grain length, ratio of length to width, and 1 000-grain weight of Z744 were significantly higher than those in Nipponbare. The plant height, panicle number, and seed-set ratio in Z744 were significantly lower than those in Nipponbare, but they were still 78.7 cm, 13.5 per plant, and 86.49%, respectively. Furthermore, eight QTLs of different traits were identified in the secondary F2 population, constructed by Nipponbare and Z744 hybridization. The grain weight of Z744 was controlled by two synergistic QTLs(qGWT1 and q GWT7) and two subtractive QTLs(qGWT2 and qGWT6), respectively. The increase in the grain weight of Z744 was caused mainly by the increase in grain length. Two QTLs were detected, qGL1 and qGL7-3, which accounted for 25.54 and 15.58% of phenotypic variation, respectively. A Chi-square test showed that the long-grain number and the short-grain number were in accordance with the 3:1 separation ratio, which indicates that the long grain is dominant over the short-grain and Z744 was controlled mainly by the principal effect qGL1. These results offered a good basis for further fine mapping of qGL1 and further dissection of other QTLs into single-segment Substitution lines.

关键词： rice chromosome segment Substitution line grain length QTL

Efficient construction of a Substitution box based on a Mordell elliptic curve over a finite field

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Frontiers of Information Technology & Electronic Engineering 2019年第10期20卷 1378-1389页

作者： Naveed Ahmed AZAM Umar HAYAT Ikram ULLAH Department of Applied Mathematics and Physics Graduate School of InformaticsKyoto UniversityKyoto 606-8501Japan Department of Mathematics Quaid-i-Azam UniversityIslamabad 44000Pakistan

Elliptic curve cryptography has been used in many security systems due to its small key size and high security compared with other cryptosystems. In many well-known security systems, a Substitution box (S-box) is the only non-linear component. Recently, it has been shown that the security of a cryptosystem can be improved using dynamic S-boxes instead of a static S-box. This necessitates the construction of new secure S-boxes. We propose an efficient method to generate S-boxes that are based on a class of Mordell elliptic curves over prime fields and achieved by defining different total orders. The proposed scheme is devel-oped in such a way that for each input it outputs an S-box in linear time and constant space. Due to this property, our method takes less time and space than the existing S-box construction methods over elliptic curves. Computational results show that the pro-posed method is capable of generating cryptographically strong S-boxes with security comparable to some of the existing S-boxes constructed via different mathematical structures.

关键词： Substitution box Finite field Mordell elliptic curve Total order Computational complexity

Thermal and Mechanical Properties Optimization of ABO4 Type EuNbO4 By the B-Site Substitution of Ta

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Engineering 2020年第2期6卷 178-185页

作者： Lin Chen Jing Feng Faculty of Material Science and Engineering Kunming University of Science and TechnologyKunming 650093China

Ferroelastic ABO4 type RETaO4 and RENbO4 ceramics(where RE stands for rare earth)are being investigated as promising thermal barrier coatings(TBCs),and the mechanical properties of RETaO4 have been found to be better than those of RENbO4.In this work,B-site Substitution of tantalum(Ta)is used to optimize the thermal and mechanical properties of EuNbO4 fabricated through a solid-state reaction(SSR).The crystal structure is clarified by means of X-ray diffraction(XRD)and Raman spectroscopy;and the surface microstructure is surveyed via scanning electronic microscope(SEM).The Young’s modulus and the thermal expansion coefficient(TEC)of EuNbO4 are effectively increased;with respective maximum values of 169 GPa and 11.2×10^-6 K^-1(at 1200℃).The thermal conductivity is reduced to 1.52 W·K^-1·m^-1(at 700℃),and the thermal radiation resistance is improved.The relationship between the phonon thermal diffusivity and temperature was established in order to determine the intrinsic phonon thermal conductivity by eliminating the thermal radiation effects.The results indicate that the thermal and mechanical properties of EuNbO4 can be effectually optimized via the B-site Substitution of Ta,and that this proposed material can be applied as a high-temperature structural ceramic in future.

关键词： Thermal barrier coatings Rare earth niobates Substitution Thermal conductivity Thermal expansion coefficients Young’s modulus