Indus basin hosts many significant mineral deposits like gypsum and cement raw materials, gemstones, iron, coal, marble, dimension and construction stones, petroleum and water resources, world class pink salt and othe...Indus basin hosts many significant mineral deposits like gypsum and cement raw materials, gemstones, iron, coal, marble, dimension and construction stones, petroleum and water resources, world class pink salt and other many minerals in different regions which need further exploitation and development. The construction of new water dams in different regions are vital (for availability of cheap electricity), because of available barren and fertile lands and wastage of water as flood. Further the installation of more cement industries in different regions of Indus Basin especially in middle Indus (Sulaiman Range where gypsum, clays and limestones can be available via belt) can increase export to receive more foreign exchange and make local cement cheap for the sustainable development of Pakistan. 31 stratigraphic sequential sections at different sections of Indus basins are presented to know the variation and local stratigraphy. Further here three new titanosaur taxa are being described. Saraikimasoom is based on snout;Gspsaurus, (Maojandino), Nicksaurus and Khanazeem are based on cranial, vertebral and appendicular elements;Balochisaurus, Marisaurus, Pakisaurus, and 3 new genera and species Imrankhanhero zilefatmi, Qaikshaheen masoomniazi and Ikqaumishan smqureshi based on vertebral and appendicular elements;and Sulaimanisaurus and Khetranisaurus based on only caudal vertebrae. Although Pakistani Titanosaurians seem to be proliferated found from one horizon of Vitakri Formation just below the K-Pg boundary they have a wide range of diagnostic features and key elements among titanosaurs which can be used for comparison and phylogenetic analyses with broad updated character data set of titanosaurs.展开更多
Quasi-solid electrolytes(QSEs)based on nanoporous materials are promising candidates to construct high-performance Limetal batteries(LMBs).However,simultaneously boosting the ionic conductivity(σ)and lithium-ion tran...Quasi-solid electrolytes(QSEs)based on nanoporous materials are promising candidates to construct high-performance Limetal batteries(LMBs).However,simultaneously boosting the ionic conductivity(σ)and lithium-ion transference number(t^(+)) of liquid electrolyte confined in porous matrix remains challenging.Herein,we report a novel Janus MOFLi/MSLi QSEs with asymmetric porous structure to inherit the benefits of both mesoporous and microporous hosts.This Janus QSE composed of mesoporous silica and microporous MOF exhibits a neat Li^(+) conductivity of 1.5.10^(–4)S cm^(−1) with t^(+) of 0.71.A partially de-solvated structure and preference distribution of Li^(+)near the Lewis base O atoms were depicted by MD simulations.Meanwhile,the nanoporous structure enabled efficient ion flux regulation,promoting the homogenous deposition of Li^(+).When incorporated in Li||Cu cells,the MOFLi/MSLi QSEs demonstrated a high Coulombic efficiency of 98.1%,surpassing that of liquid electrolytes(96.3%).Additionally,NCM 622||Li batteries equipped with MOFLi/MSLi QSEs exhibited promising rate performance and could operate stably for over 200 cycles at 1 C.These results highlight the potential of Janus MOFLi/MSLi QSEs as promising candidates for next-generation LMBs.展开更多
Polyimide(PI)is a promising electronic packaging material,but it remains challenging to obtain an all-organic PI hybrid film with decreased dielectric constant and loss without modifying the monomer.Herein,a series of...Polyimide(PI)is a promising electronic packaging material,but it remains challenging to obtain an all-organic PI hybrid film with decreased dielectric constant and loss without modifying the monomer.Herein,a series of allorganic PI hybrid films were successfully prepared by introducing the covalent organic framework(COF),which could induce the formation of the cross-linking structure in the PI matrix.Due to the synergistic effects of the COF fillers and the cross-linking structure,the PI/COF hybrid film containing 2 wt%COF exhibited the lowest dielectric constant of 2.72 and the lowest dielectric loss(tanδ)of 0.0077 at 1 MHz.It is attributed to the intrinsic low dielectric constant of COF and a large number of mesopores within the PI.Besides,the cross-linking network of PI prevents the molecular chains from stacking and improves the fraction of free volume(FFV).The molecular dynamics simulation results are well consistent with the dielectric properties data.Furthermore,the PI/COF hybrid film with 5 wt%COF showed a significant enhancement in breakdown strength,which increased to 412.8 kV/mm as compared with pure PI.In addition,the PI/COF hybrid film achieve to reduce the dielectric constant and thermal expansion coefficient(CTE).It also exhibited excellent thermal,hydrophobicity,and mechanical performance.The all-organic PI/COF hybrid films have great commercial potential as next-generation electronic packaging materials.展开更多
Different solvothermal reactions of ZnC2O_(4)with oxalic acid(H_(2)ox)and 1,2,4-triazole(Htrz)successfully gave a new quaternary(NJTU-Bai83,NJTU-Bai=Nanjing Tech University Bai's group)and a new quinary(NJTU-Bai84...Different solvothermal reactions of ZnC2O_(4)with oxalic acid(H_(2)ox)and 1,2,4-triazole(Htrz)successfully gave a new quaternary(NJTU-Bai83,NJTU-Bai=Nanjing Tech University Bai's group)and a new quinary(NJTU-Bai84)anionic metal-organic frameworks(MOFs),where NJTU-Bai83=(Me_(2)NH_(2))2[Zn_(3)(trz)_(2)(ox)_(3)]·2H_(2)O and NJTU-Bai84=(Me_(2)NH_(2))[Zn_(3)(trz)_(3)(ox)_(2)]·H_(2)O,respectively.With the[Zn_(2)(ox)4(trz)_(2)]secondary building unit(SBU)in NJTU-Bai83 replaced by the[Zn_(3)(ox)_(2)(trz)_(6)]and planar[Zn(ox)_(2)(trz)_(2)]ones in NJTU-Bai84,2D supramolecular building layers(SBLs)are changed from the A-layer and B-layer to another A-layer,while pillars are transformed from the tetrahedral[Zn(ox)_(2)(trz)_(2)]SBU to the irregular tetrahedral[Zn(ox)_(2)(trz)_(2)]and planar[Zn(ox)_(2)(trz)_(2)]SBUs.Thus,cdq-topological quaternary NJTU-Bai83 is tuned to(4,4,8)-c new topological quinary NJTU-Bai84.Two MOFs were well characterized by powder X-ray diffraction,thermogravimetric analysis,elemental analysis,etc.CCDC:2351819,NJTU-Bai83;2351820,NJTU-Bai84.展开更多
The establishment of efficient oxygen evolution electrocatalysts is of great value but also challenging.Herein,a durable metal–organic framework(MOF)with minor atomically dispersed ruthenium and an optimized electron...The establishment of efficient oxygen evolution electrocatalysts is of great value but also challenging.Herein,a durable metal–organic framework(MOF)with minor atomically dispersed ruthenium and an optimized electronic structure is constructed as an efficient electrocatalyst.Significantly,the obtained NiRu_(0.08)-MOF with doping Ru only needs an overpotential of 187 mV at 10 mA cm^(-2) with a Tafel slop of 40 mV dec^(-1) in 0.1M KOH for the oxygen evolution reaction,and can work continuously for more than 300 h.Ultrahigh Ru mass activity is achieved,reaching 56.7 Ag^(-1)_(Ru) at an overpotential of 200 mV,which is 36 times higher than that of commercial RuO_(2).X-ray adsorption spectroscopy and density function theory calculations reveal that atomically dispersed ruthenium on metal sites in MOFs is expected to optimize the electronic structure of nickel sites,thus improving the conductivity of the catalyst and optimizing the adsorption energy of intermediates,resulting in significant optimization of electrocatalytic performance.This study could provide a new avenue for the design of efficient and stable MOF electrocatalysts.展开更多
Rational design of hierarchically structured electrocatalysts is particularly important for electrocatalytic oxygen reduction reaction(ORR).Here,ZIF-67 crystals are stringed on core-shell Ag@C nanocables using a coord...Rational design of hierarchically structured electrocatalysts is particularly important for electrocatalytic oxygen reduction reaction(ORR).Here,ZIF-67 crystals are stringed on core-shell Ag@C nanocables using a coordinationmodulated process.Upon pyrolysis,Ag@C strings of Co nanoparticles embedded with three-dimensional porous carbon with beads-on-string hierarchical structures are developed.Due to the advantages of the rich electrochemical active sites of Co-based“beads”and the efficient electron transfer pathways via Ag@C“strings,”the resultant NH_(3)-Ag@C@Co-N-C-700 catalyst shows an improved electrocatalytic activity toward ORR.NH_(3)-Ag@C@Co-N-C-700 shows a high onset potential of 0.99 V versus RHE,a high half-wave potential of 0.88 V versus RHE,and a large limiting current of 5.8 mA cm^(-2),which are better than those of commercial Pt/C electrocatalysts.Additionally,the NH_(3)-Ag@C@Co-N-C-700 catalyst shows high stability and preeminent methanol tolerance,which makes NH_(3)-Ag@C@Co-N-C-700 a promising catalyst for oxygen electrocatalysis in fuel cell applications.展开更多
A new coordination framework, {[Zn(L1)(5-nipc)]·H2O}n(1, L1 = 4ˊ-(4-pyridyl)-4,2ˊ:6ˊ,4ˊˊ-terpyridine, 5-nipc = 5-nitroisophthalic acid), has been prepared under hydrothermal conditions, and determin...A new coordination framework, {[Zn(L1)(5-nipc)]·H2O}n(1, L1 = 4ˊ-(4-pyridyl)-4,2ˊ:6ˊ,4ˊˊ-terpyridine, 5-nipc = 5-nitroisophthalic acid), has been prepared under hydrothermal conditions, and determined by single-crystal X-ray diffraction analyses and further characterized by elemental analyses, IR and powder X-ray diffraction. Complex 1 crystallizes in monoclinic, space group C2/c with a = 29.983(9), b = 13.709(3), c = 14.391(3)A, β = 114.93(4)°, V = 5364(2) A3, Dc = 1.493 g/cm^3, C28H19N5O7 Zn, Mr = 602.85, F(000) = 2464, μ(Mo Kα) = 0.972 mm^-1, Z = 8, R = 0.0935 and w R = 0.1509 for 4724 observed reflections(I 〉 2σ(I)). The structure of 1 exhibits a three-dimensional(3D) network with a layer-pillar structure. The fluorescence property of 1 is also investigated.展开更多
The East China Sea shelf basin is a key area for setting up the sea level changes of Cenozoic in the West Pacific. Based upon the characteristics of seismic reflection, the analysis of sequence stratigraphy and depos...The East China Sea shelf basin is a key area for setting up the sea level changes of Cenozoic in the West Pacific. Based upon the characteristics of seismic reflection, the analysis of sequence stratigraphy and depositional system, the high resolution chronostratigraphic framework has been set up by using the data of micropaleontologic biozone fossils. The relative sea level change curve has been set up by combining analysis of paleoecology, genetic facies, specific sedimentary structures and on lap recognized from the seismic profiles with study of geochemical characteristics. There are 4 2nd order basin cycles showing the long term sea level changes, and 22 3rd order cycles showing short term ones with relative changing ranges of 0-150 m. Transgression and regression showing long term sea level changes bear asymmetric feature, which indicates that the speed of transgression is faster than that of regression. There are a lot of differences when compared with Haq ’s curve. The sequence stratigraphic framework has also been set up and 3 tectonic sequences, 7 supersequences and 19 sequences have been subdivided for Tertiary in the East China Sea shelf basin. On the basis of detailed analysis of genetic facies and log facies, 9 sedimentary systems, 20 depositional assemblages and many genetic facies have also been recognized and investigated. Based on the studies mentioned above, the favorable source and reservoir facies of gas and petroleum are indicated.展开更多
One novel metal-organic framework(MOF), [Ba(L)(HO)](1, HL =aniline-2,5-disulfonic acid), has been synthesized by hydrothermal method. Each barium atom is eleven-coordinated into a distorted monocapped pentagonal antip...One novel metal-organic framework(MOF), [Ba(L)(HO)](1, HL =aniline-2,5-disulfonic acid), has been synthesized by hydrothermal method. Each barium atom is eleven-coordinated into a distorted monocapped pentagonal antiprismatic arrangement. Compound 1 shows an interesting 3 D pillar-layered structure constructed from 2 D inorganic layers[Ba(SO)(HO)]and organic pillars of phenyl moieties of L2-linkages. The inorganic layers are supported by the organic pillars, generating a novel 3 D open framework structure with {3, 4~6, 5~5, 6~5,7~4}2{3}{5} topology. The result of fluorescence measurement can reveal that the decayed emission band centered at 492 nm may be caused by the interactions of the ligands and the metal ions.Compound 1 exhibits selective toward the adsorption of COover Nat 273 K.展开更多
Evolutionary algorithm is time-consuming because of the large number of evolutions and much times of finite element analysis, when it is used to optimize the wing structure of a certain high altitude long endurance un...Evolutionary algorithm is time-consuming because of the large number of evolutions and much times of finite element analysis, when it is used to optimize the wing structure of a certain high altitude long endurance unmanned aviation vehicle(UAV). In order to improve efficiency it is proposed to construct a model management framework to perform the multi-objective optimization design of wing structure. The sufficient accurate approximation models of objective and constraint functions in the wing structure optimization model are built when using the model management framework, therefore in the evolutionary algorithm a number of finite element analyses can he avoided and the satisfactory multi-objective optimization results of the wing structure of the high altitude long endurance UAV are obtained.展开更多
A novel zeolite-like metal-organic framework, [Cd12(trz)12'F10'(SiF6)3]·(H3O)4 (Htrz = 1,2,4-triazole), has been synthesized under solvothermal conditions using 1H-l,2,4-triazole-3- carboxylic acid and ...A novel zeolite-like metal-organic framework, [Cd12(trz)12'F10'(SiF6)3]·(H3O)4 (Htrz = 1,2,4-triazole), has been synthesized under solvothermal conditions using 1H-l,2,4-triazole-3- carboxylic acid and CdF2 as the starting materials. The complex has been characterized by elemental analysis, IR, SEM-EDS, gas adsorption, powder and single-crystal X-ray diffraction analyses. The title complex crystallizes in the cubic 1-43m space group, with a = 14.6436(8), V= 3140.1(3)A3, Z = 2, Mr = 2857.96, D,.= 3.023 g/cm3 and F(000) = 2668. The final R = 0.0653 and wR = 0.1880 for 586 observed reflections with 1 〉 2σ(I). In the title complex, three adjacent Cd(ll) centers are connected by three p3-bridging triazole ligands to form triagonal secondary building units (SBUs), which are further interconnected to form a three-dimensional skeleton with tetrahedral cages.展开更多
Late Permian stratigraphic, sedimentary and paleotectonic studies along a corridor profile across the Yangtze paleocontinent and its southern margin reveal the sedimentary evolution, subdivide the depositional sequenc...Late Permian stratigraphic, sedimentary and paleotectonic studies along a corridor profile across the Yangtze paleocontinent and its southern margin reveal the sedimentary evolution, subdivide the depositional sequences, and reconstruct the stratigraphic framework based on lateral correlation and tracing of the bounding surfaces and depositional systems. This corridor profile transects the Yangtze craton and a molasse sag zone in its southern margin. It is demonstrated that the Late Permian sedimentary evolution along the investigated profile evidently resulted from the interplay of sea level change, differential subsidence and sediment supply within the given tectonic units. In the cratonic interior, high frequency sea level fluctuation exerts an important control on the formation of the third order and fourth order sequences, and is the basis for transfacies correlation. The evolution of sequence succession in the taphrogenic zone is so much affected by the intense tectonic subsidence that it is hardly correlatable to that in the cratonic interior.展开更多
This paper puts forward the concept of land use structure optimization under space_time coupling through analyzing the systematic characteristic of land use structure optimization.It mainly expounds the construction o...This paper puts forward the concept of land use structure optimization under space_time coupling through analyzing the systematic characteristic of land use structure optimization.It mainly expounds the construction of land use structure optimization model at different levels.Lastly,this paper explains the practicableness of land use structure optimization under systematic framework through the example of Qionghai city.展开更多
The Zhongtiao Mountains, a typical exposure area of Precambrian rocks, are a concentration area of vari-ous types of copper deposit. The rocks were dated using several dating methods. Based on the age data ob-tained b...The Zhongtiao Mountains, a typical exposure area of Precambrian rocks, are a concentration area of vari-ous types of copper deposit. The rocks were dated using several dating methods. Based on the age data ob-tained by means of three methods, several aspects are dealt with: (1) the dating results obtained by differentmethods and their geological implications have been compared; (2) a chronotectonic framework has been con-structed by means of these reliable ages, which indicates that the ages of the rocks of the Proterozoic mobilebelt fall in a time span of 2400 to 2000 Ma during which global magmatic records are lacking and reflects theages of important events in the mobile belt; (3) according to the ages of inherited zircons, neodymium modelage of the depleted mantle sources (T_(DM)) and geochemical and geological data, a model of Precambrianchronocrustal structure has been constructed, representing a typical for the North China craton.展开更多
The bis(tributyltin) ester of succinic acid was synthesized by the reaction of disodium salt of succinic acid with tributyltin chloride in a molar ratio of 1:2. The crystal structure was determined by X-ray single-cry...The bis(tributyltin) ester of succinic acid was synthesized by the reaction of disodium salt of succinic acid with tributyltin chloride in a molar ratio of 1:2. The crystal structure was determined by X-ray single-crystal diffraction. It belongs to orthorhombic with space group Pccn, a = 20.949(3), b = 17.470(3), c = 20.345(3) Angstrom, V = 7446(2) Angstrom(3), Z = 8, D-c = 1.242 g/cm(3), mu = 1.365 mm(-1), F(000) = 2864, R = 0.0544 and wR = 0.1417. The tin atom is of five-coordination in a trigonal bipyramidal structure by bridging two carboxylate groups in different directions and the resulting structure which contains straight twist large ring channels along the axes of a, b and c is a three-dimensional framework polymer containing two different tin atoms.展开更多
A new Zn(Ⅱ) coordination polymer,namely {[Zn_(1.5)(1,3,5-btc^(3-))(dtb)(H_2O)](H_2O)_2}_n(1)(1,3,5-H_3btc = 1,3,5-benzenetricarboxylic acid,dtb = 1,3-di-(1,2,4-triazole-4-yl)benzene),has been hydr...A new Zn(Ⅱ) coordination polymer,namely {[Zn_(1.5)(1,3,5-btc^(3-))(dtb)(H_2O)](H_2O)_2}_n(1)(1,3,5-H_3btc = 1,3,5-benzenetricarboxylic acid,dtb = 1,3-di-(1,2,4-triazole-4-yl)benzene),has been hydrothermally synthesized and structurally characterized. X-ray single-crystal diffraction determination reveals that 1 crystallizes in the monoclinic C2/c space group with a = 33.811(12),b = 8.406(2),c = 17.296(4) ?,β = 120.593(2)°,V = 4232(2) ?~3,Z = 4,Mr = 1142.88,Dc = 1.794 Mg/m^3,μ = 1.783 mm^(-1),F(000) = 2320,the final R = 0.0338 and wR = 0.0827 for 3043 observed reflections with I 〉 2σ(I). Compound 1 exhibits 1D Zn(Ⅱ)-carboxylate chains,which are connected into a 3D porous framework with large channels by dtb,and then three identical 3D networks are interpenetrated with each other. In addition,the luminescence property of the complex has also been investigated.展开更多
Two different CdⅡ coordination frameworks [Cd(L1)(L2)]∞(1) and [Cd(L1)-(L3)(H2O)]∞(2) based on a flexible dicarboxylic acid ligand were obtained by introducing two different nitrogen heterocyclic auxiliary ligands(...Two different CdⅡ coordination frameworks [Cd(L1)(L2)]∞(1) and [Cd(L1)-(L3)(H2O)]∞(2) based on a flexible dicarboxylic acid ligand were obtained by introducing two different nitrogen heterocyclic auxiliary ligands(L1 = 3,3’-[1,3-benzenebis(carbonylimino)]bi(benzoate), L2 = 1,3-bi(4-pyridyl)propane, L3 = 4,4’-bipyridine). Complex 1 crystallizes in triclinic, space group P■ with a = 8.7415(5), b = 12.2247(7), c =16.2415(10) ?, β = 95.6790(10)°, V = 1525.11(16) ?3, Dc = 1.553 mg·m-3, C35H28CdN4O6, Mr = 713.02, F(000) = 724, μ(MoKα) = 0.770 mm–1, Z = 2, R/wR(I > 2σ(I))a = 0.0302/0.0773. However, complex 2 crystallizes in monoclinic, space group P21/n with a = 11.4986(7), b = 23.0911(14), c = 11.9943(8) ?, β = 115.9500(10)°, V = 2863.6(3) ?3, Dc = 1.598 mg·m-3, C32H24CdN4O7, Mr = 688.96, F(000) = 1392, μ(MoKα) = 0.820 mm–1, Z = 4, R/wR(I > 2σ(I))a = 0.0283/0.0631. The structures of two complexes were characterized. Complexes 1 and 2 have different one-dimensional(1D) chain structures. In addition, we have also made a preliminary study on the properties of the two complexes.展开更多
Multiple failure modes tend to be identified in the reliability analysis of a redundant truss structure.This identification process involves updating the model for identifying the next potential failure members.Herein...Multiple failure modes tend to be identified in the reliability analysis of a redundant truss structure.This identification process involves updating the model for identifying the next potential failure members.Herein we intend to update the finite element model automatically in the identification process of failure modes and further perform the system reliability analysis efficiently.This study presents a framework that is implemented through the joint simulation of MATLAB and APDL and consists of three parts:reliability index of a single member,identification of dominant failure modes,and system-level reliability analysis for system reliability analysis of truss structures.Firstly,RSM(response surface method)combines with a constrained optimization model to calculate the reliability indices ofmembers.Then theβ-unzipping method is adopted to identify the dominant failuremodes,and the system function in MATLAB,as well as the EKILL command in APDL,is used to facilitate the automatic update of the finite element model and realize load-redistribution.Besides,the differential equivalence recursion algorithmis performed to approximate the reliability indices of failuremodes efficiently and accurately.Eventually,the PNET(probabilistic network evaluation technique)is used to calculate the joint failure probability as well as the system reliability index.Two illustrative examples demonstrate the accuracy and efficiency of the proposed system reliability analysis framework through comparison with corresponding references.展开更多
The Cryogenian is a critical period in the history of the Earth. It is marked by multiple extreme climate changes that caused alternating global glacial and interglacial intervals. These dramatically changed the sedim...The Cryogenian is a critical period in the history of the Earth. It is marked by multiple extreme climate changes that caused alternating global glacial and interglacial intervals. These dramatically changed the sedimentary system, and metal ores and source rocks distributed widely during this period. Therefore, studying the Cryogenian stratigraphic framework and sedimentary basins is important to improve the stratigraphic resolution for metal mineral and hydrocarbon prospecting and exploration in China. This review paper firstly divides three tectonic-stratigraphic regions in China in the Cryogenian, including the tectonic-stratigraphic regions of Great South China, Xingmeng-Tarim, and North China. Secondly, geochronologic data and geological records are combined to clearly depict the Cryogenian sedimentary sequence of continental blocks and micro-continental blocks in different tectonic-stratigraphic regions. The results were used to propose a new comparison scheme of stratigraphy for the Cryogenian in China. Finally, according to differences of sedimentary evolution and tectonic evolvement, sedimentary basins and their lithofacies paleogeography are identified and summarized, respectively.展开更多
A magnesium metal organic framework, [N-H2(CH3)2][-N(CH3)4][Mgs(bpdc)3(O2CH)6]· 3H2O (1, bpdcH2 = 4,4'-biphenyldicarboxylic acid), has been solvothermally synthesized and structurally characterized. 1 ...A magnesium metal organic framework, [N-H2(CH3)2][-N(CH3)4][Mgs(bpdc)3(O2CH)6]· 3H2O (1, bpdcH2 = 4,4'-biphenyldicarboxylic acid), has been solvothermally synthesized and structurally characterized. 1 crystallizes in the trigonal system, space group R-3, with a = 11.3427(3), c = 41.5662(18) A, V = 4631.3(3) A^3, Z = 3 and the final R = 0.0457. Its structure features a pillared-layered three-dimensional network with 8.21 A cavities, in which cationic [NH2(CH3)2]^+ or [N(CH3)4]^+ and lattice water molecules are located. Thermal stability of the title compound has also been investigated.展开更多
文摘Indus basin hosts many significant mineral deposits like gypsum and cement raw materials, gemstones, iron, coal, marble, dimension and construction stones, petroleum and water resources, world class pink salt and other many minerals in different regions which need further exploitation and development. The construction of new water dams in different regions are vital (for availability of cheap electricity), because of available barren and fertile lands and wastage of water as flood. Further the installation of more cement industries in different regions of Indus Basin especially in middle Indus (Sulaiman Range where gypsum, clays and limestones can be available via belt) can increase export to receive more foreign exchange and make local cement cheap for the sustainable development of Pakistan. 31 stratigraphic sequential sections at different sections of Indus basins are presented to know the variation and local stratigraphy. Further here three new titanosaur taxa are being described. Saraikimasoom is based on snout;Gspsaurus, (Maojandino), Nicksaurus and Khanazeem are based on cranial, vertebral and appendicular elements;Balochisaurus, Marisaurus, Pakisaurus, and 3 new genera and species Imrankhanhero zilefatmi, Qaikshaheen masoomniazi and Ikqaumishan smqureshi based on vertebral and appendicular elements;and Sulaimanisaurus and Khetranisaurus based on only caudal vertebrae. Although Pakistani Titanosaurians seem to be proliferated found from one horizon of Vitakri Formation just below the K-Pg boundary they have a wide range of diagnostic features and key elements among titanosaurs which can be used for comparison and phylogenetic analyses with broad updated character data set of titanosaurs.
基金supported by National Natural Science Foundation of China(Grant No.22005266)Zhejiang Provincial Natural Science Foundation(Grant No.LR21E020003)“the Fundamental Research Funds for the Central Universities”(2021FZZX001-09).
文摘Quasi-solid electrolytes(QSEs)based on nanoporous materials are promising candidates to construct high-performance Limetal batteries(LMBs).However,simultaneously boosting the ionic conductivity(σ)and lithium-ion transference number(t^(+)) of liquid electrolyte confined in porous matrix remains challenging.Herein,we report a novel Janus MOFLi/MSLi QSEs with asymmetric porous structure to inherit the benefits of both mesoporous and microporous hosts.This Janus QSE composed of mesoporous silica and microporous MOF exhibits a neat Li^(+) conductivity of 1.5.10^(–4)S cm^(−1) with t^(+) of 0.71.A partially de-solvated structure and preference distribution of Li^(+)near the Lewis base O atoms were depicted by MD simulations.Meanwhile,the nanoporous structure enabled efficient ion flux regulation,promoting the homogenous deposition of Li^(+).When incorporated in Li||Cu cells,the MOFLi/MSLi QSEs demonstrated a high Coulombic efficiency of 98.1%,surpassing that of liquid electrolytes(96.3%).Additionally,NCM 622||Li batteries equipped with MOFLi/MSLi QSEs exhibited promising rate performance and could operate stably for over 200 cycles at 1 C.These results highlight the potential of Janus MOFLi/MSLi QSEs as promising candidates for next-generation LMBs.
基金supported by National Natural Science Foundation of China(52103029 and 51903075).
文摘Polyimide(PI)is a promising electronic packaging material,but it remains challenging to obtain an all-organic PI hybrid film with decreased dielectric constant and loss without modifying the monomer.Herein,a series of allorganic PI hybrid films were successfully prepared by introducing the covalent organic framework(COF),which could induce the formation of the cross-linking structure in the PI matrix.Due to the synergistic effects of the COF fillers and the cross-linking structure,the PI/COF hybrid film containing 2 wt%COF exhibited the lowest dielectric constant of 2.72 and the lowest dielectric loss(tanδ)of 0.0077 at 1 MHz.It is attributed to the intrinsic low dielectric constant of COF and a large number of mesopores within the PI.Besides,the cross-linking network of PI prevents the molecular chains from stacking and improves the fraction of free volume(FFV).The molecular dynamics simulation results are well consistent with the dielectric properties data.Furthermore,the PI/COF hybrid film with 5 wt%COF showed a significant enhancement in breakdown strength,which increased to 412.8 kV/mm as compared with pure PI.In addition,the PI/COF hybrid film achieve to reduce the dielectric constant and thermal expansion coefficient(CTE).It also exhibited excellent thermal,hydrophobicity,and mechanical performance.The all-organic PI/COF hybrid films have great commercial potential as next-generation electronic packaging materials.
文摘Different solvothermal reactions of ZnC2O_(4)with oxalic acid(H_(2)ox)and 1,2,4-triazole(Htrz)successfully gave a new quaternary(NJTU-Bai83,NJTU-Bai=Nanjing Tech University Bai's group)and a new quinary(NJTU-Bai84)anionic metal-organic frameworks(MOFs),where NJTU-Bai83=(Me_(2)NH_(2))2[Zn_(3)(trz)_(2)(ox)_(3)]·2H_(2)O and NJTU-Bai84=(Me_(2)NH_(2))[Zn_(3)(trz)_(3)(ox)_(2)]·H_(2)O,respectively.With the[Zn_(2)(ox)4(trz)_(2)]secondary building unit(SBU)in NJTU-Bai83 replaced by the[Zn_(3)(ox)_(2)(trz)_(6)]and planar[Zn(ox)_(2)(trz)_(2)]ones in NJTU-Bai84,2D supramolecular building layers(SBLs)are changed from the A-layer and B-layer to another A-layer,while pillars are transformed from the tetrahedral[Zn(ox)_(2)(trz)_(2)]SBU to the irregular tetrahedral[Zn(ox)_(2)(trz)_(2)]and planar[Zn(ox)_(2)(trz)_(2)]SBUs.Thus,cdq-topological quaternary NJTU-Bai83 is tuned to(4,4,8)-c new topological quinary NJTU-Bai84.Two MOFs were well characterized by powder X-ray diffraction,thermogravimetric analysis,elemental analysis,etc.CCDC:2351819,NJTU-Bai83;2351820,NJTU-Bai84.
基金National Natural Science Foundation of China,Grant/Award Number:51632008。
文摘The establishment of efficient oxygen evolution electrocatalysts is of great value but also challenging.Herein,a durable metal–organic framework(MOF)with minor atomically dispersed ruthenium and an optimized electronic structure is constructed as an efficient electrocatalyst.Significantly,the obtained NiRu_(0.08)-MOF with doping Ru only needs an overpotential of 187 mV at 10 mA cm^(-2) with a Tafel slop of 40 mV dec^(-1) in 0.1M KOH for the oxygen evolution reaction,and can work continuously for more than 300 h.Ultrahigh Ru mass activity is achieved,reaching 56.7 Ag^(-1)_(Ru) at an overpotential of 200 mV,which is 36 times higher than that of commercial RuO_(2).X-ray adsorption spectroscopy and density function theory calculations reveal that atomically dispersed ruthenium on metal sites in MOFs is expected to optimize the electronic structure of nickel sites,thus improving the conductivity of the catalyst and optimizing the adsorption energy of intermediates,resulting in significant optimization of electrocatalytic performance.This study could provide a new avenue for the design of efficient and stable MOF electrocatalysts.
基金Higher Education Discipline Innovation Project,Grant/Award Number:D17007Xinxiang Major Science and Technology Projects,Grant/Award Number:21ZD001+1 种基金Henan Center for Outstanding Overseas Scientists,Grant/Award Number:GZS2022017National Natural Science Foundation of China,Grant/Award Numbers:51872075,51922008,52072114。
文摘Rational design of hierarchically structured electrocatalysts is particularly important for electrocatalytic oxygen reduction reaction(ORR).Here,ZIF-67 crystals are stringed on core-shell Ag@C nanocables using a coordinationmodulated process.Upon pyrolysis,Ag@C strings of Co nanoparticles embedded with three-dimensional porous carbon with beads-on-string hierarchical structures are developed.Due to the advantages of the rich electrochemical active sites of Co-based“beads”and the efficient electron transfer pathways via Ag@C“strings,”the resultant NH_(3)-Ag@C@Co-N-C-700 catalyst shows an improved electrocatalytic activity toward ORR.NH_(3)-Ag@C@Co-N-C-700 shows a high onset potential of 0.99 V versus RHE,a high half-wave potential of 0.88 V versus RHE,and a large limiting current of 5.8 mA cm^(-2),which are better than those of commercial Pt/C electrocatalysts.Additionally,the NH_(3)-Ag@C@Co-N-C-700 catalyst shows high stability and preeminent methanol tolerance,which makes NH_(3)-Ag@C@Co-N-C-700 a promising catalyst for oxygen electrocatalysis in fuel cell applications.
基金supported by the Startup Foundation for Doctors of Jinzhong University
文摘A new coordination framework, {[Zn(L1)(5-nipc)]·H2O}n(1, L1 = 4ˊ-(4-pyridyl)-4,2ˊ:6ˊ,4ˊˊ-terpyridine, 5-nipc = 5-nitroisophthalic acid), has been prepared under hydrothermal conditions, and determined by single-crystal X-ray diffraction analyses and further characterized by elemental analyses, IR and powder X-ray diffraction. Complex 1 crystallizes in monoclinic, space group C2/c with a = 29.983(9), b = 13.709(3), c = 14.391(3)A, β = 114.93(4)°, V = 5364(2) A3, Dc = 1.493 g/cm^3, C28H19N5O7 Zn, Mr = 602.85, F(000) = 2464, μ(Mo Kα) = 0.972 mm^-1, Z = 8, R = 0.0935 and w R = 0.1509 for 4724 observed reflections(I 〉 2σ(I)). The structure of 1 exhibits a three-dimensional(3D) network with a layer-pillar structure. The fluorescence property of 1 is also investigated.
文摘The East China Sea shelf basin is a key area for setting up the sea level changes of Cenozoic in the West Pacific. Based upon the characteristics of seismic reflection, the analysis of sequence stratigraphy and depositional system, the high resolution chronostratigraphic framework has been set up by using the data of micropaleontologic biozone fossils. The relative sea level change curve has been set up by combining analysis of paleoecology, genetic facies, specific sedimentary structures and on lap recognized from the seismic profiles with study of geochemical characteristics. There are 4 2nd order basin cycles showing the long term sea level changes, and 22 3rd order cycles showing short term ones with relative changing ranges of 0-150 m. Transgression and regression showing long term sea level changes bear asymmetric feature, which indicates that the speed of transgression is faster than that of regression. There are a lot of differences when compared with Haq ’s curve. The sequence stratigraphic framework has also been set up and 3 tectonic sequences, 7 supersequences and 19 sequences have been subdivided for Tertiary in the East China Sea shelf basin. On the basis of detailed analysis of genetic facies and log facies, 9 sedimentary systems, 20 depositional assemblages and many genetic facies have also been recognized and investigated. Based on the studies mentioned above, the favorable source and reservoir facies of gas and petroleum are indicated.
基金supported by the Liaoning Provincial Education Department(No.L2015299)Innovative training program for College Students(Nos.201710148000118,201710148000147)
文摘One novel metal-organic framework(MOF), [Ba(L)(HO)](1, HL =aniline-2,5-disulfonic acid), has been synthesized by hydrothermal method. Each barium atom is eleven-coordinated into a distorted monocapped pentagonal antiprismatic arrangement. Compound 1 shows an interesting 3 D pillar-layered structure constructed from 2 D inorganic layers[Ba(SO)(HO)]and organic pillars of phenyl moieties of L2-linkages. The inorganic layers are supported by the organic pillars, generating a novel 3 D open framework structure with {3, 4~6, 5~5, 6~5,7~4}2{3}{5} topology. The result of fluorescence measurement can reveal that the decayed emission band centered at 492 nm may be caused by the interactions of the ligands and the metal ions.Compound 1 exhibits selective toward the adsorption of COover Nat 273 K.
文摘Evolutionary algorithm is time-consuming because of the large number of evolutions and much times of finite element analysis, when it is used to optimize the wing structure of a certain high altitude long endurance unmanned aviation vehicle(UAV). In order to improve efficiency it is proposed to construct a model management framework to perform the multi-objective optimization design of wing structure. The sufficient accurate approximation models of objective and constraint functions in the wing structure optimization model are built when using the model management framework, therefore in the evolutionary algorithm a number of finite element analyses can he avoided and the satisfactory multi-objective optimization results of the wing structure of the high altitude long endurance UAV are obtained.
基金National Natural Science Foundation of China(21101090)Natural Science Foundation of Jiangxi Province(20114BAB213001)Education Department of Jiangxi Province(GJJ12041)
文摘A novel zeolite-like metal-organic framework, [Cd12(trz)12'F10'(SiF6)3]·(H3O)4 (Htrz = 1,2,4-triazole), has been synthesized under solvothermal conditions using 1H-l,2,4-triazole-3- carboxylic acid and CdF2 as the starting materials. The complex has been characterized by elemental analysis, IR, SEM-EDS, gas adsorption, powder and single-crystal X-ray diffraction analyses. The title complex crystallizes in the cubic 1-43m space group, with a = 14.6436(8), V= 3140.1(3)A3, Z = 2, Mr = 2857.96, D,.= 3.023 g/cm3 and F(000) = 2668. The final R = 0.0653 and wR = 0.1880 for 586 observed reflections with 1 〉 2σ(I). In the title complex, three adjacent Cd(ll) centers are connected by three p3-bridging triazole ligands to form triagonal secondary building units (SBUs), which are further interconnected to form a three-dimensional skeleton with tetrahedral cages.
文摘Late Permian stratigraphic, sedimentary and paleotectonic studies along a corridor profile across the Yangtze paleocontinent and its southern margin reveal the sedimentary evolution, subdivide the depositional sequences, and reconstruct the stratigraphic framework based on lateral correlation and tracing of the bounding surfaces and depositional systems. This corridor profile transects the Yangtze craton and a molasse sag zone in its southern margin. It is demonstrated that the Late Permian sedimentary evolution along the investigated profile evidently resulted from the interplay of sea level change, differential subsidence and sediment supply within the given tectonic units. In the cratonic interior, high frequency sea level fluctuation exerts an important control on the formation of the third order and fourth order sequences, and is the basis for transfacies correlation. The evolution of sequence succession in the taphrogenic zone is so much affected by the intense tectonic subsidence that it is hardly correlatable to that in the cratonic interior.
文摘This paper puts forward the concept of land use structure optimization under space_time coupling through analyzing the systematic characteristic of land use structure optimization.It mainly expounds the construction of land use structure optimization model at different levels.Lastly,this paper explains the practicableness of land use structure optimization under systematic framework through the example of Qionghai city.
文摘The Zhongtiao Mountains, a typical exposure area of Precambrian rocks, are a concentration area of vari-ous types of copper deposit. The rocks were dated using several dating methods. Based on the age data ob-tained by means of three methods, several aspects are dealt with: (1) the dating results obtained by differentmethods and their geological implications have been compared; (2) a chronotectonic framework has been con-structed by means of these reliable ages, which indicates that the ages of the rocks of the Proterozoic mobilebelt fall in a time span of 2400 to 2000 Ma during which global magmatic records are lacking and reflects theages of important events in the mobile belt; (3) according to the ages of inherited zircons, neodymium modelage of the depleted mantle sources (T_(DM)) and geochemical and geological data, a model of Precambrianchronocrustal structure has been constructed, representing a typical for the North China craton.
基金the National Natural Science Foundation of China (No. 20271025)the Natural Science Foundation of Shandong province (No. Z2001B02)the State Key Laboratory of Crystal Materials,Shandong University
文摘The bis(tributyltin) ester of succinic acid was synthesized by the reaction of disodium salt of succinic acid with tributyltin chloride in a molar ratio of 1:2. The crystal structure was determined by X-ray single-crystal diffraction. It belongs to orthorhombic with space group Pccn, a = 20.949(3), b = 17.470(3), c = 20.345(3) Angstrom, V = 7446(2) Angstrom(3), Z = 8, D-c = 1.242 g/cm(3), mu = 1.365 mm(-1), F(000) = 2864, R = 0.0544 and wR = 0.1417. The tin atom is of five-coordination in a trigonal bipyramidal structure by bridging two carboxylate groups in different directions and the resulting structure which contains straight twist large ring channels along the axes of a, b and c is a three-dimensional framework polymer containing two different tin atoms.
基金supported by the National Natural Science Foundation of China(21372112)the Science and Technology Research Projects of Education Department of Henan Province(15A150064)
文摘A new Zn(Ⅱ) coordination polymer,namely {[Zn_(1.5)(1,3,5-btc^(3-))(dtb)(H_2O)](H_2O)_2}_n(1)(1,3,5-H_3btc = 1,3,5-benzenetricarboxylic acid,dtb = 1,3-di-(1,2,4-triazole-4-yl)benzene),has been hydrothermally synthesized and structurally characterized. X-ray single-crystal diffraction determination reveals that 1 crystallizes in the monoclinic C2/c space group with a = 33.811(12),b = 8.406(2),c = 17.296(4) ?,β = 120.593(2)°,V = 4232(2) ?~3,Z = 4,Mr = 1142.88,Dc = 1.794 Mg/m^3,μ = 1.783 mm^(-1),F(000) = 2320,the final R = 0.0338 and wR = 0.0827 for 3043 observed reflections with I 〉 2σ(I). Compound 1 exhibits 1D Zn(Ⅱ)-carboxylate chains,which are connected into a 3D porous framework with large channels by dtb,and then three identical 3D networks are interpenetrated with each other. In addition,the luminescence property of the complex has also been investigated.
基金supported by the National Natural Science Foundation of China(21501078)the fund for Shanxi “1331 Project” Key Innovative Research Team+1 种基金the Natural Science Foundation of Shanxi Province(2015011026)the 1331 Project for Innovation Team Construction Plan of Jinzhong University
文摘Two different CdⅡ coordination frameworks [Cd(L1)(L2)]∞(1) and [Cd(L1)-(L3)(H2O)]∞(2) based on a flexible dicarboxylic acid ligand were obtained by introducing two different nitrogen heterocyclic auxiliary ligands(L1 = 3,3’-[1,3-benzenebis(carbonylimino)]bi(benzoate), L2 = 1,3-bi(4-pyridyl)propane, L3 = 4,4’-bipyridine). Complex 1 crystallizes in triclinic, space group P■ with a = 8.7415(5), b = 12.2247(7), c =16.2415(10) ?, β = 95.6790(10)°, V = 1525.11(16) ?3, Dc = 1.553 mg·m-3, C35H28CdN4O6, Mr = 713.02, F(000) = 724, μ(MoKα) = 0.770 mm–1, Z = 2, R/wR(I > 2σ(I))a = 0.0302/0.0773. However, complex 2 crystallizes in monoclinic, space group P21/n with a = 11.4986(7), b = 23.0911(14), c = 11.9943(8) ?, β = 115.9500(10)°, V = 2863.6(3) ?3, Dc = 1.598 mg·m-3, C32H24CdN4O7, Mr = 688.96, F(000) = 1392, μ(MoKα) = 0.820 mm–1, Z = 4, R/wR(I > 2σ(I))a = 0.0283/0.0631. The structures of two complexes were characterized. Complexes 1 and 2 have different one-dimensional(1D) chain structures. In addition, we have also made a preliminary study on the properties of the two complexes.
基金support from the National Key R&D Program of China(Grant Nos.2021YFB2600605,2021YFB2600600)the Overseas Scholar Program in the Hebei Province(C20190514)+1 种基金from the State Key Laboratory of Mechanical Behavior and System Safety of Traffic Engineering Structures Project(ZZ2020-20)from the Youth Foundation of Hebei Science and Technology Research Project(QN2018108).
文摘Multiple failure modes tend to be identified in the reliability analysis of a redundant truss structure.This identification process involves updating the model for identifying the next potential failure members.Herein we intend to update the finite element model automatically in the identification process of failure modes and further perform the system reliability analysis efficiently.This study presents a framework that is implemented through the joint simulation of MATLAB and APDL and consists of three parts:reliability index of a single member,identification of dominant failure modes,and system-level reliability analysis for system reliability analysis of truss structures.Firstly,RSM(response surface method)combines with a constrained optimization model to calculate the reliability indices ofmembers.Then theβ-unzipping method is adopted to identify the dominant failuremodes,and the system function in MATLAB,as well as the EKILL command in APDL,is used to facilitate the automatic update of the finite element model and realize load-redistribution.Besides,the differential equivalence recursion algorithmis performed to approximate the reliability indices of failuremodes efficiently and accurately.Eventually,the PNET(probabilistic network evaluation technique)is used to calculate the joint failure probability as well as the system reliability index.Two illustrative examples demonstrate the accuracy and efficiency of the proposed system reliability analysis framework through comparison with corresponding references.
基金supported by National Key Research and Development Program of China(2016YFC0601005)the Geological Survey of China(DD20190370),National Science Foundation of China(41772107)+1 种基金the 13th Fiveyear Plan of the Ministry of Science and Technology of China(2016ZX05034-002-003)the National Postdoctoral Program for Innovative Talents(BX20180278)。
文摘The Cryogenian is a critical period in the history of the Earth. It is marked by multiple extreme climate changes that caused alternating global glacial and interglacial intervals. These dramatically changed the sedimentary system, and metal ores and source rocks distributed widely during this period. Therefore, studying the Cryogenian stratigraphic framework and sedimentary basins is important to improve the stratigraphic resolution for metal mineral and hydrocarbon prospecting and exploration in China. This review paper firstly divides three tectonic-stratigraphic regions in China in the Cryogenian, including the tectonic-stratigraphic regions of Great South China, Xingmeng-Tarim, and North China. Secondly, geochronologic data and geological records are combined to clearly depict the Cryogenian sedimentary sequence of continental blocks and micro-continental blocks in different tectonic-stratigraphic regions. The results were used to propose a new comparison scheme of stratigraphy for the Cryogenian in China. Finally, according to differences of sedimentary evolution and tectonic evolvement, sedimentary basins and their lithofacies paleogeography are identified and summarized, respectively.
基金supported by the NNSFC (No. 20873149)the Knowledge Innovation Program of the Chinese Academy of Sciences (KJCX2-XW-H21)
文摘A magnesium metal organic framework, [N-H2(CH3)2][-N(CH3)4][Mgs(bpdc)3(O2CH)6]· 3H2O (1, bpdcH2 = 4,4'-biphenyldicarboxylic acid), has been solvothermally synthesized and structurally characterized. 1 crystallizes in the trigonal system, space group R-3, with a = 11.3427(3), c = 41.5662(18) A, V = 4631.3(3) A^3, Z = 3 and the final R = 0.0457. Its structure features a pillared-layered three-dimensional network with 8.21 A cavities, in which cationic [NH2(CH3)2]^+ or [N(CH3)4]^+ and lattice water molecules are located. Thermal stability of the title compound has also been investigated.