Two dinuclear organotin complexes C8H14(CO2SnCy3)2(1)(Cy = cyclohexyl group) and C8H14[CO2Sn(CH2CMe2Ph)3]2(2) were synthesized by the reactions of camphoric acid with tricyclohexyltin hydroxide and bis[tri(...Two dinuclear organotin complexes C8H14(CO2SnCy3)2(1)(Cy = cyclohexyl group) and C8H14[CO2Sn(CH2CMe2Ph)3]2(2) were synthesized by the reactions of camphoric acid with tricyclohexyltin hydroxide and bis[tri(2-methyl-2-phenyl)propyltin] oxide under solvothermal conditions, and these complexes were characterized by infrared spectra, elemental analyses, and H NMR spectra. The crystal of 1 belongs to the monoclinic system, space group P21/c with a = 1.83478(19), b = 1.52707(18), c = 1.9849(2) nm, β = 122.515(7)°, Z = 4, V = 4.6896(9) nm^3, Dc = 1.324 g/cm^3, μ(MoKα) = 1.103 mm^-1, F(000) = 1952, R = 0.0697 and wR = 0.2040. In addition, thermal stability and quantum chemical calculation of 1 were also studied.展开更多
Hexaacetyl D-mannose hydrazine is one type of important intermediates in saccharide chemistry. In this paper, its single crystal was obtained and furthermore, X-ray diffraction and quantum chemistry calculation were p...Hexaacetyl D-mannose hydrazine is one type of important intermediates in saccharide chemistry. In this paper, its single crystal was obtained and furthermore, X-ray diffraction and quantum chemistry calculation were performed. It belongs to orthorhombic system, space group P212121, with a=16.267(3), b=19.263(3), c=7.1948(12)A, Mr=446.41, Dc=1.315 g/cm^3, V=2254.5(6)A^3 and Z=4. Meanwhile, the experimental results also provide information for designing a kind of molecular switch based on the mannose nitrogenous derivatives.展开更多
La_(0.68)Pb_(0.32)FeO_3 samples annealed at different temperature were prepared using citrate sol-gel method. With increasing of annealing temperature from 200 to 1000 ℃, the samples crystallize to have single-phase ...La_(0.68)Pb_(0.32)FeO_3 samples annealed at different temperature were prepared using citrate sol-gel method. With increasing of annealing temperature from 200 to 1000 ℃, the samples crystallize to have single-phase perovskite structure. However, the sensitivity increases at first due to the improvement of crystallization of the perovskite phase, and finally drops attributed to the larger grain size. The optimal sensitivities for La_(0.68)Pb_(0.32)FeO_3 samples annealed at 400, 600, 800, and 1000 ℃ are 12.14, 14.77, 51.07, and 34.55, respectively.展开更多
The high electrical conductivity and high specific surface area of graphene are traditionally regarded as the most intriguing features for its promise as the electrode material for supercapacitors. In this perspective...The high electrical conductivity and high specific surface area of graphene are traditionally regarded as the most intriguing features for its promise as the electrode material for supercapacitors. In this perspective, we highlight that from the engineering point of view, the unique colloidal chemistry of chemically functionalized graphene is the key property that has made graphene stand out as a promising nanoscale building block for constructing unique nanoporous electrodes for capacitive energy storage, We present several examples to demonstrate bow the non-covalent colloidal forces between graphene sheets can be harnessed to engineer the nanostructure of graphene-based bulk electrodes for supercapacitors based on both the electrical double layer storage and the redox reaction or pseudo-capacitance mechanisms. The colloidal engineering strategy can be extended to enable other nanomaterials to achieve high energy storage performance.展开更多
The title compound l-benzyl-5-((4-methoxyphenyl)ethynyl)-4-phenyl-1H-1,2,3-triazole(C24H19N3O) was designed and synthesized using one-pot strategy and structural characterization was done by single-crystal X-ray...The title compound l-benzyl-5-((4-methoxyphenyl)ethynyl)-4-phenyl-1H-1,2,3-triazole(C24H19N3O) was designed and synthesized using one-pot strategy and structural characterization was done by single-crystal X-ray diffraction,NMR,IR and MS.This compound was crystallized out from an ethanolic solution in triclinic system,space group P1 with a =9.9038(9),b = 10.2928(9),c = 18.8715(19)A°,α = 103.541(6),β = 90.507(7),γ = 97.157(7)°,V =1854.2(3) A°3,Z = 4,crystal size(mm) = 0.25 × 0.1 × 0.1 and R(int) = 0.068.Its asymmetric unit contains two independent molecules.The crystal structure of the title compound is stabilized by intramolecular interactions of types C-H…N and C-H…O.Additionally,X-ray analysis reveals obvious C-H…π,π-π stacking interactions between two adjacent aromatic ring planes.展开更多
The burnable poison Gadolinium oxide was incorporated into UO<sub>2</sub> in two of the 36 elements of the fuel assembly in the reload fuel of BWR Units I & II of Tarapur Atomic Power Station. This ena...The burnable poison Gadolinium oxide was incorporated into UO<sub>2</sub> in two of the 36 elements of the fuel assembly in the reload fuel of BWR Units I & II of Tarapur Atomic Power Station. This enabled loading of higher quantities of fuel and achieving a more flattened neutron flux distribution over a longer period of time in the nuclear reactor core. The UO<sub>2</sub>-Gd<sub>2</sub>O<sub>3</sub> pellets are made by powder pressing and sintering. In the early days of this author’s experience of the 1970s, the processing of UO<sub>2</sub>-Gd<sub>2</sub>O<sub>3</sub> turned out to be more complex than that of UO<sub>2</sub> alone. The small proportion of Gd<sub>2</sub>O<sub>3</sub> in the powder mixture (1.5%) is to be uniformly distributed in the UO<sub>2</sub> before and after sintering and substitutional solid solution formation must be complete prior to densification. The inadequacy of homogeneity in the powder and pressed pellets leads to severe defects in the sintering process. In this paper, the processing of U<sub>2</sub>-Gd<sub>2</sub>O<sub>3</sub> has been revisited. The defects in the product such as “free gadolinia”, low sintered density and bloating, caused by improper processing, have been brought out. The structural defect chemistry aspects of UO<sub>2</sub>-Gd<sub>2</sub>O<sub>3</sub> and diffusion processes relevant to sintering have also been discussed.展开更多
Cultivated hawthorn(Crataegus pinnatifida var.major),the principal cultivated hawthorn species in China,is rich in phenolic compounds.These phytochemicals are considered essential bioactive ingredients in different or...Cultivated hawthorn(Crataegus pinnatifida var.major),the principal cultivated hawthorn species in China,is rich in phenolic compounds.These phytochemicals are considered essential bioactive ingredients in different organs of cultivated hawthorn,contributing to its health effects.However,there is lack of a comprehensive review that systematically summarizes the chemistry,health effects,and stability of phenolic substances.This review summarizes recent progress in the characterization,classification,and distribution of phenolic compounds in C.pinnatifida var.major,including procyanidins,flavonoids,phenolic acids,lignans,and others.Importantly,the stability of these compounds was found to be influenced by factors such as the hawthorn development process,postharvest storage,postharvest processing,and the gastrointestinal tract environment.Additionally,the health effects of phenolic compounds in cultivated hawthorn and their underlying mechanisms were discussed.This review provides valuable insights into the utilization of hawthorn resources and the development of the hawthorn industry.展开更多
A nickel(Ⅱ) complex containing both dithiolato and phosphine ligands, Ni_2(PPh_3)_2(edt)_2 (edt = SCH_2CH_2S^(2-)), has been prepared and characterized by X-ray diffration. The complex crystallizes in the triclinic s...A nickel(Ⅱ) complex containing both dithiolato and phosphine ligands, Ni_2(PPh_3)_2(edt)_2 (edt = SCH_2CH_2S^(2-)), has been prepared and characterized by X-ray diffration. The complex crystallizes in the triclinic system, space group P-1, with a = 10.693(3), b = 17.457 (6), c = 10.606 (3)A, α= 102.84(2), β = 96.49 (2), γ = 82.56(3)°; V = 1906.8 A^3; D_c = 1.439g.cm^(-3) for Z=2; the final con- ventional R was 0.052 based on 3338 observed reflections. Nickel atoms are linked by two sulfur atoms from two edt ligands with the Ni--Ni distance of 2.893 A, and each Ni atom is coordinated by one phosphorus atom and three sulfur atoms with a square-planar geometry, where the average: length of Ni--S bond is 2.180 A and Ni--P bond 2.188 A. The UV-Vis and ~1H NMR spectra have also been recorded.展开更多
The structure and rheological properties of carbon-based particle suspensions, i.e., carbon black(CB), multi-wall carbon nanotube(MWNT), graphene and hollow carbon sphere(HCS) suspended in polydimethylsiloxane(...The structure and rheological properties of carbon-based particle suspensions, i.e., carbon black(CB), multi-wall carbon nanotube(MWNT), graphene and hollow carbon sphere(HCS) suspended in polydimethylsiloxane(PDMS), are investigated. In order to study the effect of particle shape on the structure and rheological properties of suspensions, the content of surface oxygen-containing functional groups of carbon-based particles is controlled to be similar. Original spherical-like CB(fractal filler), rod-like MWNT and sheet-like graphene form large agglomerates in PDMS, while spherical HCS particles disperse relatively well in PDMS. The dispersion state of carbon-based particles affects the critical concentration of forming a rheological percolation network. Under weak shear, negative normal stress differences(ΔN) are observed in CB, MWNT and graphene suspensions, while ΔN is nearly zero for HCS suspensions. It is concluded that the vorticity alignment of CB, MWNT and graphene agglomerates under shear results in the negative ΔN. However, no obvious structural change is observed in HCS suspension under weak shear, and accordingly, the ΔN is almost zero.展开更多
Metal clusters that contain a small number of atoms usually present unique properties with dramatic dependence on their sizes,geometric structures,and compositions.The studies of naked metal clusters are devoted to de...Metal clusters that contain a small number of atoms usually present unique properties with dramatic dependence on their sizes,geometric structures,and compositions.The studies of naked metal clusters are devoted to develop new catalysts and functional materials of atomic precision,and enable to improve the fundamental theory of structure chemistry and to understand the basic reactions and properties bridging the gap between atoms and bulk materials.In particular,some interesting superatom clusters have received reasonable research interest indicative of materials gene of clusters.Here in this review,we simply summarize the preparation,stability,and reactivity of naked metal clusters with a few examples displayed.Hopefully it serves as a modest spur to stimulate more interest of related investigations in this field.展开更多
Oxychalcogenides have been drawn much attention to be explored as nonlinear optical(NLO)materials in recent years.To date,all the NLO oxychalcogenides crystallize in low dimensional structures.Herein,a new oxysulfide ...Oxychalcogenides have been drawn much attention to be explored as nonlinear optical(NLO)materials in recent years.To date,all the NLO oxychalcogenides crystallize in low dimensional structures.Herein,a new oxysulfide K_(2)Ba_(0.5)Ga_(9)O_(2)S_(13) was obtained via three-dimensional(3D){[Ga_(9)O_(2)S_(13)]^(3-)}_(∞)polyanionic framework.As the first oxychalcogenide with 3D NLO-acitve polyanionic framework,K_(2)Ba_(0.5)Ga_(9)O_(2)S_(13) has a wide band gap of 3.72 eV,and exhibits a high laser-induced damage threshold(LIDT,17×AgGaS_(2)).It presents moderate phase-matchable NLO response of 0.5×AgGaS_(2) at 2.1μm and 2×KH_(2)PO_(4) at 1.064μm.The theoretical calculation results indicate that the NLO response is mainly contributed from[Ga(2)S4]unit-built[Ga(2)_(3)S_(10)]windmill-like motif.This work may stimulate the exploration of more NLO oxychalcogenides with balanced performances.展开更多
基金Supported by Natural Science Foundation of Hunan Province(No.13JJ3112)Scientific & Technological Projects of Hunan Province(No.2013TZ2025,2014NK3086)+3 种基金Open Foundation of Innovation Platform of Hunan Provincial University(No.13K105,14K014)Scientific & Technological Projects of Hengyang City(No.2012KJ30)Cultivation projects Based on Collaborative Innovation Center of Hengyang Normal University(No.12XT02)the Youth Backbone Teacher Training Program of Hengyang Normal University(2012)
文摘Two dinuclear organotin complexes C8H14(CO2SnCy3)2(1)(Cy = cyclohexyl group) and C8H14[CO2Sn(CH2CMe2Ph)3]2(2) were synthesized by the reactions of camphoric acid with tricyclohexyltin hydroxide and bis[tri(2-methyl-2-phenyl)propyltin] oxide under solvothermal conditions, and these complexes were characterized by infrared spectra, elemental analyses, and H NMR spectra. The crystal of 1 belongs to the monoclinic system, space group P21/c with a = 1.83478(19), b = 1.52707(18), c = 1.9849(2) nm, β = 122.515(7)°, Z = 4, V = 4.6896(9) nm^3, Dc = 1.324 g/cm^3, μ(MoKα) = 1.103 mm^-1, F(000) = 1952, R = 0.0697 and wR = 0.2040. In addition, thermal stability and quantum chemical calculation of 1 were also studied.
基金The project was supported by the National Natural Science Foundation of China (No. 20272031)
文摘Hexaacetyl D-mannose hydrazine is one type of important intermediates in saccharide chemistry. In this paper, its single crystal was obtained and furthermore, X-ray diffraction and quantum chemistry calculation were performed. It belongs to orthorhombic system, space group P212121, with a=16.267(3), b=19.263(3), c=7.1948(12)A, Mr=446.41, Dc=1.315 g/cm^3, V=2254.5(6)A^3 and Z=4. Meanwhile, the experimental results also provide information for designing a kind of molecular switch based on the mannose nitrogenous derivatives.
基金Project supported by the National Natural Science Foundation of China (59772040)
文摘La_(0.68)Pb_(0.32)FeO_3 samples annealed at different temperature were prepared using citrate sol-gel method. With increasing of annealing temperature from 200 to 1000 ℃, the samples crystallize to have single-phase perovskite structure. However, the sensitivity increases at first due to the improvement of crystallization of the perovskite phase, and finally drops attributed to the larger grain size. The optimal sensitivities for La_(0.68)Pb_(0.32)FeO_3 samples annealed at 400, 600, 800, and 1000 ℃ are 12.14, 14.77, 51.07, and 34.55, respectively.
基金the financial support for the Australian Research Council(FT110100341 and DP140102624)
文摘The high electrical conductivity and high specific surface area of graphene are traditionally regarded as the most intriguing features for its promise as the electrode material for supercapacitors. In this perspective, we highlight that from the engineering point of view, the unique colloidal chemistry of chemically functionalized graphene is the key property that has made graphene stand out as a promising nanoscale building block for constructing unique nanoporous electrodes for capacitive energy storage, We present several examples to demonstrate bow the non-covalent colloidal forces between graphene sheets can be harnessed to engineer the nanostructure of graphene-based bulk electrodes for supercapacitors based on both the electrical double layer storage and the redox reaction or pseudo-capacitance mechanisms. The colloidal engineering strategy can be extended to enable other nanomaterials to achieve high energy storage performance.
基金supported by the Higher Education Commision(HEC),Govt.of Pakistan
文摘The title compound l-benzyl-5-((4-methoxyphenyl)ethynyl)-4-phenyl-1H-1,2,3-triazole(C24H19N3O) was designed and synthesized using one-pot strategy and structural characterization was done by single-crystal X-ray diffraction,NMR,IR and MS.This compound was crystallized out from an ethanolic solution in triclinic system,space group P1 with a =9.9038(9),b = 10.2928(9),c = 18.8715(19)A°,α = 103.541(6),β = 90.507(7),γ = 97.157(7)°,V =1854.2(3) A°3,Z = 4,crystal size(mm) = 0.25 × 0.1 × 0.1 and R(int) = 0.068.Its asymmetric unit contains two independent molecules.The crystal structure of the title compound is stabilized by intramolecular interactions of types C-H…N and C-H…O.Additionally,X-ray analysis reveals obvious C-H…π,π-π stacking interactions between two adjacent aromatic ring planes.
文摘The burnable poison Gadolinium oxide was incorporated into UO<sub>2</sub> in two of the 36 elements of the fuel assembly in the reload fuel of BWR Units I & II of Tarapur Atomic Power Station. This enabled loading of higher quantities of fuel and achieving a more flattened neutron flux distribution over a longer period of time in the nuclear reactor core. The UO<sub>2</sub>-Gd<sub>2</sub>O<sub>3</sub> pellets are made by powder pressing and sintering. In the early days of this author’s experience of the 1970s, the processing of UO<sub>2</sub>-Gd<sub>2</sub>O<sub>3</sub> turned out to be more complex than that of UO<sub>2</sub> alone. The small proportion of Gd<sub>2</sub>O<sub>3</sub> in the powder mixture (1.5%) is to be uniformly distributed in the UO<sub>2</sub> before and after sintering and substitutional solid solution formation must be complete prior to densification. The inadequacy of homogeneity in the powder and pressed pellets leads to severe defects in the sintering process. In this paper, the processing of U<sub>2</sub>-Gd<sub>2</sub>O<sub>3</sub> has been revisited. The defects in the product such as “free gadolinia”, low sintered density and bloating, caused by improper processing, have been brought out. The structural defect chemistry aspects of UO<sub>2</sub>-Gd<sub>2</sub>O<sub>3</sub> and diffusion processes relevant to sintering have also been discussed.
基金supported by the Natural Science Foundation of Shandong Province(No.ZR2023QC228)the Key Research and Development Program of Zhejiang Province(No.2021C02001)+1 种基金the Shandong(Linyi)Institute of Modern Agriculture of Zhejiang University to Serve the Local Economic Development(Integration of Two Institutes)(No.ZDNY-2021-FWLY01004)the Fundamental Research Funds for the Central Universities(No.226-2022-00215),China.
文摘Cultivated hawthorn(Crataegus pinnatifida var.major),the principal cultivated hawthorn species in China,is rich in phenolic compounds.These phytochemicals are considered essential bioactive ingredients in different organs of cultivated hawthorn,contributing to its health effects.However,there is lack of a comprehensive review that systematically summarizes the chemistry,health effects,and stability of phenolic substances.This review summarizes recent progress in the characterization,classification,and distribution of phenolic compounds in C.pinnatifida var.major,including procyanidins,flavonoids,phenolic acids,lignans,and others.Importantly,the stability of these compounds was found to be influenced by factors such as the hawthorn development process,postharvest storage,postharvest processing,and the gastrointestinal tract environment.Additionally,the health effects of phenolic compounds in cultivated hawthorn and their underlying mechanisms were discussed.This review provides valuable insights into the utilization of hawthorn resources and the development of the hawthorn industry.
基金Project supported partly by the National Naural Science Foundation of China the Provincial Science Fund of Fujian.
文摘A nickel(Ⅱ) complex containing both dithiolato and phosphine ligands, Ni_2(PPh_3)_2(edt)_2 (edt = SCH_2CH_2S^(2-)), has been prepared and characterized by X-ray diffration. The complex crystallizes in the triclinic system, space group P-1, with a = 10.693(3), b = 17.457 (6), c = 10.606 (3)A, α= 102.84(2), β = 96.49 (2), γ = 82.56(3)°; V = 1906.8 A^3; D_c = 1.439g.cm^(-3) for Z=2; the final con- ventional R was 0.052 based on 3338 observed reflections. Nickel atoms are linked by two sulfur atoms from two edt ligands with the Ni--Ni distance of 2.893 A, and each Ni atom is coordinated by one phosphorus atom and three sulfur atoms with a square-planar geometry, where the average: length of Ni--S bond is 2.180 A and Ni--P bond 2.188 A. The UV-Vis and ~1H NMR spectra have also been recorded.
基金financially supported by the National Natural Science Foundation of China(Nos.21474111,21222407 and 21274152)subsidized by the National Basic Research Program of China(973 Program,2012CB821500)
文摘The structure and rheological properties of carbon-based particle suspensions, i.e., carbon black(CB), multi-wall carbon nanotube(MWNT), graphene and hollow carbon sphere(HCS) suspended in polydimethylsiloxane(PDMS), are investigated. In order to study the effect of particle shape on the structure and rheological properties of suspensions, the content of surface oxygen-containing functional groups of carbon-based particles is controlled to be similar. Original spherical-like CB(fractal filler), rod-like MWNT and sheet-like graphene form large agglomerates in PDMS, while spherical HCS particles disperse relatively well in PDMS. The dispersion state of carbon-based particles affects the critical concentration of forming a rheological percolation network. Under weak shear, negative normal stress differences(ΔN) are observed in CB, MWNT and graphene suspensions, while ΔN is nearly zero for HCS suspensions. It is concluded that the vorticity alignment of CB, MWNT and graphene agglomerates under shear results in the negative ΔN. However, no obvious structural change is observed in HCS suspension under weak shear, and accordingly, the ΔN is almost zero.
基金financially supported by the National Natural Science Foundation of China (Nos. 21802146 and 21722308)CAS Key Research Project of Frontier Science (CAS Grant QYZDB-SSW-SLH024)Frontier Cross Project of National Laboratory for Molecular Sciences (051Z011BZ3)。
文摘Metal clusters that contain a small number of atoms usually present unique properties with dramatic dependence on their sizes,geometric structures,and compositions.The studies of naked metal clusters are devoted to develop new catalysts and functional materials of atomic precision,and enable to improve the fundamental theory of structure chemistry and to understand the basic reactions and properties bridging the gap between atoms and bulk materials.In particular,some interesting superatom clusters have received reasonable research interest indicative of materials gene of clusters.Here in this review,we simply summarize the preparation,stability,and reactivity of naked metal clusters with a few examples displayed.Hopefully it serves as a modest spur to stimulate more interest of related investigations in this field.
基金support by the National Natural Science Foundation of China(21771159,22071212)Qinglan Project of Jiangsu Province of China.
文摘Oxychalcogenides have been drawn much attention to be explored as nonlinear optical(NLO)materials in recent years.To date,all the NLO oxychalcogenides crystallize in low dimensional structures.Herein,a new oxysulfide K_(2)Ba_(0.5)Ga_(9)O_(2)S_(13) was obtained via three-dimensional(3D){[Ga_(9)O_(2)S_(13)]^(3-)}_(∞)polyanionic framework.As the first oxychalcogenide with 3D NLO-acitve polyanionic framework,K_(2)Ba_(0.5)Ga_(9)O_(2)S_(13) has a wide band gap of 3.72 eV,and exhibits a high laser-induced damage threshold(LIDT,17×AgGaS_(2)).It presents moderate phase-matchable NLO response of 0.5×AgGaS_(2) at 2.1μm and 2×KH_(2)PO_(4) at 1.064μm.The theoretical calculation results indicate that the NLO response is mainly contributed from[Ga(2)S4]unit-built[Ga(2)_(3)S_(10)]windmill-like motif.This work may stimulate the exploration of more NLO oxychalcogenides with balanced performances.