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Population-based X-ray gastric cancer screening in Hiroshima prefecture, Japan
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作者 Nhu Thi Hanh Vu Yuji Urabe +2 位作者 Duc Trong Quach Shiro Oka Toru Hiyama 《World Journal of Clinical Oncology》 2024年第2期271-281,共11页
BACKGROUND X-ray gastric cancer(GC)screening has been shown to decrease mortality.Population-based X-ray GC screening has been performed in Hiroshima Prefe-cture,Japan,since 1983 but time trends and the efficacy of th... BACKGROUND X-ray gastric cancer(GC)screening has been shown to decrease mortality.Population-based X-ray GC screening has been performed in Hiroshima Prefe-cture,Japan,since 1983 but time trends and the efficacy of the method over 39 years have not been assessed.METHODS This was a population-based retrospective study.The data were derived from aggregated data of the Hiroshima Regional Health Medical Promotion Organization,including the number and rate of participants and those requiring esophagogastroduodenoscopies(EGDs),the number and rate of participants diagnosed as having GC,and the positive predictive value of the abnormal findings detected by X-ray and confirmed by EGDs.The number and rate of esophageal cancers were also collected.Further,the cost of detecting one GC was evaluated.RESULTS The number of participants has decreased during the last four decades,from 39925 in 1983 to 12923 in 2021.The rate of those requiring EGDs decreased significantly in recent years(P<0.001).The number of participants diagnosed as having GC has also declined,from 76 to 10 cases.However,the rate of cases diagnosed as GC among the participants remained around 0.1%.The positive predictive value increased significantly in recent years except during 1983-1991.The number and rate of accidentally detected esophageal cancers have risen recently,from 0%in 2008 to 0.02%in 2021,one-fifth of the diagnosis rate of GC.One GC diagnosis costs approximately 4200000 Japanese Yen(30000 United States Dollars)for the X-ray screenings and EGDs.CONCLUSION X-ray GC screening in Hiroshima has been efficient,but one challenge is the cost.Esophageal cancers may also need to be considered because they have gradually increased in recent years. 展开更多
关键词 Population Retrospective studies x-ray Gastric cancer SCREENING
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Optical 2-benzyl-5-hydroxy-4-oxopentanoic acids against carboxypeptidase A:Synthesis,kinetic evaluation and X-ray crystallographic study 被引量:1
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作者 Wang, Shou Feng Jin, Jing-Yi +1 位作者 Zeng, Zong Hao Tian, Guan Rong 《Chinese Chemical Letters》 SCIE CAS CSCD 2010年第2期159-162,共4页
2-Benzyl-5-hydroxy-4-oxopentanoic acid 1 and its enantiomers were designed,synthesized and assayed for inhibitory activity against carboxypeptidase A(CPA,EC 3.4.17.1).To verify the role of the terminal hydroxyl group ... 2-Benzyl-5-hydroxy-4-oxopentanoic acid 1 and its enantiomers were designed,synthesized and assayed for inhibitory activity against carboxypeptidase A(CPA,EC 3.4.17.1).To verify the role of the terminal hydroxyl group in 1 binding to CPA,2-benzyl-5- benzyloxy-4-oxopentanoic acid 2 was also synthesized and evaluated.The inhibition constants show that both L-1 and D-1 were shown to have strong binding affinity with L-1 being more potent than its enantiomer by 165-fold.On the other hand,the inhibition constant ... 展开更多
关键词 2-Benzyl-5-hydroxy-4-oxopentanoic acid Carboxypeptidase A x-ray crystallographic study
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Synchrotron X-Ray Diffraction Studies on the New Generation Ferromagnetic Semiconductor Li(Zn,Mn)As under High Pressure 被引量:1
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作者 孙菲 徐丛 +5 位作者 于爽 陈碧娟 赵国强 邓正 杨文革 靳常青 《Chinese Physics Letters》 SCIE CAS CSCD 2017年第6期100-103,共4页
The pressure effect on the crystalline structure of the I-II- V semiconductor Li(Zn,Mn)As ferromagnet is studied using in situ high-pressure x-ray diffraction and diamond anvil cell techniques. A phase transition st... The pressure effect on the crystalline structure of the I-II- V semiconductor Li(Zn,Mn)As ferromagnet is studied using in situ high-pressure x-ray diffraction and diamond anvil cell techniques. A phase transition starting at -11.6GPa is found. The space group of the high-pressure new phase is proposed as Pmca. Fitting with the Birch-Murnaghan equation of state, the bulk modulus B0 and its pressure derivative B0 of the ambient pressure structure with space group of F43m are B0 = 75.4 GPa and B0 = 4.3, respectively. 展开更多
关键词 AS Zn Mn)As under High Pressure Synchrotron x-ray Diffraction Studies on the New Generation Ferromagnetic Semiconductor Li MN
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Radial X-Ray Diffraction Study of Static Strength of Tantalum to 80 GPa 被引量:1
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作者 熊伦 白利刚 +1 位作者 李晓东 刘景 《Chinese Physics Letters》 SCIE CAS CSCD 2017年第10期60-64,共5页
We study the strength and texture of tantalum (Ta) under uniaxiM compression up to 80 GPa using an angle-dispersive radial x-ray diffraction technique together with the lattice strain theory in a diamond anvil cell ... We study the strength and texture of tantalum (Ta) under uniaxiM compression up to 80 GPa using an angle-dispersive radial x-ray diffraction technique together with the lattice strain theory in a diamond anvil cell at ambient temperature. The ratio of differential stress to shear modulus (t/G) is found to remain constant above -60GPa, indicating that the Ta starts to experience macro yield with plastic deformation at this pressure.Combined with independent constraints on the high-pressure shear modulus, we find that the Ta sample could support a differential stress of -4.67 GPa when it starts to yield with plastic deformation at -60 CPa under unlaxial compression. The differential stress in Ta ranges from 0.216 GPa to 4.67CPa with pressure increasing from 1 GPa to 60GPa and can be expressed as t=0.199(33)+0.075(1)P, where P is the pressure in GPa. A maximum differential stress as high as -5.37 GPa can be supported by Ta at the high pressure of -80 GPa. In addition, we investigate the texture of Ta under nonhydrostatic compression to 80 GPa using the software package material analysis using diffraction. It is proven that the plastic deformation due to stress under high pressures is responsible for the development of texture. 展开更多
关键词 TA Radial x-ray Diffraction study of Static Strength of Tantalum to 80 GPa
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X-ray Crystallinity Studies of Palladium Polyacrylate
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作者 R.Hussain and D.Mohammad (Pakistan Institute of Nuclear Science and Technology, P.O.Box 1356, Islamabad, Pakistan) 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 1995年第4期310-312,共3页
Free radical polymerized palladium polyacrylate was characterized by X-ray diffraction. Various parameters including mean crystallite size, interchain separation and radius of gyration have been calculated and discuss... Free radical polymerized palladium polyacrylate was characterized by X-ray diffraction. Various parameters including mean crystallite size, interchain separation and radius of gyration have been calculated and discussed with respect to the concentration of Pd in the polymeric salt. The results show that polymer is predominantly amorphous in nature. 展开更多
关键词 UK x-ray Crystallinity Studies of Palladium Polyacrylate John
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X-ray Diffraction and Electrical Conductivity Studies on Ag-Cu-Se System
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作者 S.N.Motafa and S.R.Selim(Chemistry Department, Al-Azhar University, Nasr City. Cairo. Egypt)F.M.Ismail(Inorganic Chemistry Department, National Research Center. Dokki. Cairo. Egypt) 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 1995年第1期53-55,共3页
A number of X-ray patterns and electrical conductivities of five different samples of Ag-Cu-Se system have been measured. These samples of Ag-Cu-Se system: (Ag1.188, Cu0.812)Se, (Ag,Cu)Se; (Ag0.9, Cu1.1 )Se, (Ag0.8, C... A number of X-ray patterns and electrical conductivities of five different samples of Ag-Cu-Se system have been measured. These samples of Ag-Cu-Se system: (Ag1.188, Cu0.812)Se, (Ag,Cu)Se; (Ag0.9, Cu1.1 )Se, (Ag0.8, Cu1.2)Se and (Ag0.6, Cu1.4)Se were prepared under controlled conditions. Analysis of the experimental data shows that Frenkel defects are predominated in (Ag1.188, Cu0.812)Se and Schottky defects prevailing in the other samples. The activation energy values △E calculated from the linear behaviour of electrical conductivity a with temperature (0-90℃) reveal that the impurity content increases in the direction of (Ag,Cu)Se→(Ag0.8,Cu1.2 )Se 展开更多
关键词 AG x-ray Diffraction and Electrical Conductivity Studies on Ag-Cu-Se System CU
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X-RAY SCATTERING STUDIES ON NYLON-1010
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作者 莫志深 杨宝泉 +1 位作者 薛小芙 张利华 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 1992年第3期230-235,共6页
From Wide-Angle X-ray Scattering (WAXS) pattern of uniaxially orientated fibers, the crystal structure of Nylon-1010 was determined. The Nylon-1010 crystallizes in the triclinic system, with lattice dimensions: a=4.9A... From Wide-Angle X-ray Scattering (WAXS) pattern of uniaxially orientated fibers, the crystal structure of Nylon-1010 was determined. The Nylon-1010 crystallizes in the triclinic system, with lattice dimensions: a=4.9A, b=5.4A, c=27.8, α=49 °, β=77 °,γ=63.5 °, the unit cell contains one monomeric unit and the space group is P. The degree of crystallinity of polymer was deter mined as about 60%, using Ruland's method.The structures of Nylon-1010 with different draw ratio have been investigated by using Small-Angle X-ray Scattering (SAXS). The results indicate that the draw ratio of samples has a significant effect on microstructure of Nylon-1010. The long period and thickness of amorphous layer obviously increase but the invariant, average lameUar and interphase zone show almost independent of draw ratio, long period increases because amorphous layer increases with draw ratio. The electron density fluctuation values increased with draw ratio, but inner surface O_s is drecreased. 展开更多
关键词 SAXS x-ray SCATTERING STUDIES ON NYLON-1010
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X-RAY SCATIERING STUDIES ON NYLON-1010
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作者 Zhi Shen MO Bao Quan YANG Xiao Fu XUE Li Hua ZHANG Laboratory of Polymer Physics,Changchun Institute of Applied Chemistry,Academia Sinica,Changchun 130022 《Chinese Chemical Letters》 SCIE CAS CSCD 1992年第8期667-668,共2页
The structures of Nylon-1010 with different draw ratios have been investigated by using Small-Angle X-ray Scattering(SAXS).It is shown that by using a simple geometrical construction the following structure parameters... The structures of Nylon-1010 with different draw ratios have been investigated by using Small-Angle X-ray Scattering(SAXS).It is shown that by using a simple geometrical construction the following structure parameters can be directly derived from the correlation function,the long period(L),the thickness of the crystal amorphous interphase(dtr),the lamellar thickness(do),the“invariant”(Q),the specific inner surface(Os), and the electron density difference between the core of the crystallites and the amorphous matrix(η_ε-η_ω)。 展开更多
关键词 ZHANG x-ray SCATIERING STUDIES ON NYLON-1010
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X-Ray Diffraction Studies of Rice Husk Ash—An Ecofriendly Concrete at Different Temperatures
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作者 Patnaikuni Chandan Kumar Nutulapati V. S. Venugopal 《American Journal of Analytical Chemistry》 2013年第8期368-372,共5页
In the majority of rice producing countries, much of the husk produced from the processing of rice is either burnt or dumped as waste. Rice husks are one of the largest readily available but most under-utilized biomas... In the majority of rice producing countries, much of the husk produced from the processing of rice is either burnt or dumped as waste. Rice husks are one of the largest readily available but most under-utilized biomass resources, being an ideal fuel for electricity generation. In this communication the author reported the X-ray diffraction studies on rice husk ash (RHA) concrete samples heated at 300℃ and 1000℃ which were compared and observed that at 300℃ the inner surface of the specimen shows an extra compound. Copper Iron Lead Telluride Cu3FePbTe4 along with SiO2, Al5Fe2ZnO4 was present on the surface which also and might be responsible for imparting additional strength to 7.5% RHA concrete at 300℃. The X-ray diffraction studies of samples exposed to 1000℃ on temperature showed that the additional chemical compounds formed at lower temperatures were not found at 1000℃ at outer and inner surfaces of the sample indicating its possible reason for exhibiting poor strengths for all specimens. The outer surface of the 1000℃ heated specimen showed a compound named dichloroglyoxime C2H2Cl2N2O2 along with SiO2 but the inner surface of the same sample showed SiO2 alone. 展开更多
关键词 RICE Husk ASH CONCRETE x-ray DIFFRACTION Studies Different Temperature Environment
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X-Ray Radiation Sensing Properties of ZnS Thin Film:A Study on the Effect of Annealing
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作者 M.P.Sarma J.M.Kalita G.Wary 《Chinese Physics Letters》 SCIE CAS CSCD 2017年第7期262-265,共4页
Chemically synthesized ZnS thin film is found to be a good x-ray radiation sensor. We report the effect of annealing on the x-ray radiation detection sensitivity of a ZnS thin film synthesized by a chemical bath depos... Chemically synthesized ZnS thin film is found to be a good x-ray radiation sensor. We report the effect of annealing on the x-ray radiation detection sensitivity of a ZnS thin film synthesized by a chemical bath deposition technique. The chemically synthesized ZnS films are annealed at 333, 363 and 393K for 1 h. Structural analyses show that the lattice defects in the films decrease with annealing. Further, the band gap is also found to decrease from 3.38 to 3.21 eV after annealing at 393K. Current-voltage characteristics of the films are studied under dark and x-ray irradiation conditions. Due to the decrease of lattice defects and band gap, the conductivity under dark conditions is found to increase from 2.06 × 10^-6 to 1.69 × 10^-5 S/em, while that under x-ray irradiation increases from 4.13 × 10^-5 to 5.28 ×10^-5 S/cm. On the other hand, the x-ray radiation detection sensitivity of the films is found to decrease with annealing. This decrease of detection sensitivity is attributed to the decrease of the band gap as well as some structural and surface morphological changes occurring after annealing. 展开更多
关键词 ZNS x-ray Radiation Sensing Properties of ZnS Thin Film:A study on the Effect of Annealing
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A study on some elements and their phases in sediments of Changjiang Estuary by X-ray spectrometer and X-ray diffractometer
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作者 Han Jiancheng, Li Li, Chen Qiming, Wu Xinran, Chen Banglin and Han QingpingDepartment of Chemistry, East China Normal University, Shanghai 200062, China 《Acta Oceanologica Sinica》 SCIE CAS CSCD 1997年第1期121-125,共5页
INTRODUCTIONThe studies on the quantitative distribution of the conventional elements and their phases in the sediments of the Changjiang Estuary are of great importance to the understanding of the chemical processes ... INTRODUCTIONThe studies on the quantitative distribution of the conventional elements and their phases in the sediments of the Changjiang Estuary are of great importance to the understanding of the chemical processes of ion exchange, absorption, desorption and flocculation in the estuary. 展开更多
关键词 A study on some elements and their phases in sediments of Changjiang Estuary by x-ray spectrometer and x-ray diffractometer
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The Study of Supermassive Black Holes:From X-ray to Infrared
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《Bulletin of the Chinese Academy of Sciences》 2017年第3期175-176,共2页
All massive galaxies host supermassive black holes(SMBH)at their centers,and these objects are often found to be hidden behind large amounts of gas and dust.This circum-nuclear material is what eventually accretes ont... All massive galaxies host supermassive black holes(SMBH)at their centers,and these objects are often found to be hidden behind large amounts of gas and dust.This circum-nuclear material is what eventually accretes onto the black hole,allowing it to grow,and its structure and evolution has been the subject of intense study in the past decade.In a recent issue of Nature Astronomy,the Chinese Academy of Sciences South America Center 展开更多
关键词 In AGN The study of Supermassive Black Holes From x-ray to Infrared
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Synthesis, Characterization and X-ray Structure of N-(4-bromobutanoyl-N'-(2-3-and 4-methylphenyl)thiourea 被引量:3
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作者 Hamza M Abosadiya Siti Aishah Hasbullah Bohari M Yamin 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2015年第3期379-385,共7页
N-4-(bromobutanoyl)-N'-(o-, m- and p-tolyl)thioureas 3a, 3b and 3c respectively, were synthesized by the reaction of 4-bromobutanoylisothiocyanate with p-, m- and o-toludine. The products were characterized by IR... N-4-(bromobutanoyl)-N'-(o-, m- and p-tolyl)thioureas 3a, 3b and 3c respectively, were synthesized by the reaction of 4-bromobutanoylisothiocyanate with p-, m- and o-toludine. The products were characterized by IR, and NMR spectroscopic techniques. The two carbonoylthiourea isomers N-(4-bromobutanoyl)-N'-(3-methylphenyl)thiourea (3b) and N-(4-bromobutanoyl)-N'-(4- methylphenyl)thiourea (3c) were obtained in crystalline form by recrystallization from DMSO. X- ray crystallographic studies showed that both compounds 3b and 3c crystallize in triclinic system with space group ofPi. The molecules adopt trans-cis configuration with respect to the positions of 4-bromobutanoyl and tolyl groups respectively, against the thiono C=S bond across their C-N bonds The configuration is attributed by the intrahydrogen bond between the carbonyl oxygen and amide hydrogen atoms. Both crystal structures are stabilized by N-H…S intermolecular hydrogen bonds to form dimers and arranged along the b axis. 展开更多
关键词 4-bromobutyryl chloride thiourea derivatives x-ray structural study
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Synthesis, characterisation and microbial studies of [bis(1,10-phenanthroline) (ethylenediamine) copper(II)] diperchlorate and its bromide analogue
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作者 Oluwayemi O. Esther Onawumi Idowu O. Adeoye Funmi A. Adekunle 《Open Journal of Inorganic Chemistry》 2013年第1期26-33,共8页
Two new tris-chelate-complexes have been synthesized and characterized with elemental and spectroscopic methods. IR and thermal studies correlate with the structures of the complex in the solid state. The structure of... Two new tris-chelate-complexes have been synthesized and characterized with elemental and spectroscopic methods. IR and thermal studies correlate with the structures of the complex in the solid state. The structure of [Cu(en)(phen)2] was determined with X-ray data using single crystal X-ray diffractometer while the molecular structure of [Cu(en) (phen)2] 2Br - 2Phen·8H2O was deduced from the used characterization methods. [Cu(en)(phen)2]· crystallizes as orthorhombic with space group Pbcn. Both complexes have distorted octahedral geometry. Microbial activities of these complexes against Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, Streptoccocus pyogeneous, Candida albicans, and Aspergillus niger were also reported. 展开更多
关键词 Tris-Chelate Complexes x-ray Data Electronic Spectra MICROBIAL STUDIES
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Spectral studies of transition metal complexes with 25, 26 dioxo1,6,12,17,23,24 hexaazacyclohexacosa 1,5,12,16 tetraene macrocyclic ligand (L)
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作者 Sulekh Chandra Poonam Pipil 《Open Journal of Inorganic Chemistry》 2013年第4期109-115,共7页
Mn(II), Co(II), Ni(II) and Cu(II) complexes with this ligand (L) i.e. 25, 26 dioxo1,6,12,17,23,24 hexaazacyclohexacosa1,5,12,16 tetraene have been prepared. All the complexes were characterized by elemental analysis, ... Mn(II), Co(II), Ni(II) and Cu(II) complexes with this ligand (L) i.e. 25, 26 dioxo1,6,12,17,23,24 hexaazacyclohexacosa1,5,12,16 tetraene have been prepared. All the complexes were characterized by elemental analysis, molar conductance measurements, magnetic susceptibility measurements, mass, i.r. electronic, and e.p.r. spectral studies. The molar conductance measurements in DMF indicate that the Mn(II), Co(II), and Cu(II) are non-electrolyte whereas the complexes of Ni(II) are electrolyte. Thus, these complexes may by formulated as [M(L)X2] and [Ni(L)]X2 (where M = Mn(II), Co(II) and Cu(II) and X = C1- and ). All the complexes are of the high spin type expected Ni(II) complexes which are diamagnetic. On the basis of spectral studies, an octahedral geometry may be assigned of Mn(II) and Co(II). Square planar is for Ni(II) complexes, and tetragonal geometry for Cu(II) complexes. 展开更多
关键词 MASS IR Magnetic MOMENT Electronic EPR x-ray DIFFRACTION Studies
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Studies on Optical, Mechanical and Electrical Properties of Organic Nonlinear Optical p-Toluidine p-Toluenesulfonate Single Crystal
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作者 Suresh Sagadevan Priya Murugasen 《Journal of Crystallization Process and Technology》 2014年第2期99-110,共12页
The optically transparent and bulk single crystal of p-Toluidine p-Toluenesulfonate (PTPT) was grown by slow evaporation technique. The lattice parameters and crystallinity of the grown crystal were estimated by singl... The optically transparent and bulk single crystal of p-Toluidine p-Toluenesulfonate (PTPT) was grown by slow evaporation technique. The lattice parameters and crystallinity of the grown crystal were estimated by single crystal XRD. The optical absorption of the crystal was recorded using the UV-Vis-NIR spectrophotometer. The optical bandgap and optical constants of the material were determined by using absorption spectrum. The refractive index of the grown crystal has been determined using the Brewster angle method. The dielectric constant and dielectric loss were measured as a function of frequency and temperature for the grown crystal. Nonlinear optical properties were performed to confirm the SHG efficiency of the grown crystal. Hence, PTPT is an excellent NLO material with enhanced SHG efficiency required for important applications in the field of optoelectronic and photonics. This material exhibits NLO behaviour remarkably due to its better optical and dielectric properties. 展开更多
关键词 Single x-ray Diffraction UV-Vis-NIR SPECTROPHOTOMETER NLO SHG DIELECTRIC Constant DIELECTRIC Loss STUDIES
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Synthesis, Structural Characterization and Computational Studies of Bis(2-Ethylimidazole) Bis(Formato)Zinc(II)-Water (1/1)
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作者 Nana Odette Ngnabeuye Tayo Alain Djampouo +4 位作者 Ndosiri Ndoye Bridget Tanyi Rogers Fomuta Djimassingar Golngar Tagne Alain Charly Kuate Ngoune Jean 《Crystal Structure Theory and Applications》 2018年第1期1-18,共18页
The reaction of 2-ethylimidazole and zinc formate monohydrate in 1:2 ratio in toluene leads to the formation of bis(2-ethylimidazole)bis(formato)zinc(II)-water (1/1), [Zn(N2H8C5)2(OCHO)2]·H2O, 1 which has been ch... The reaction of 2-ethylimidazole and zinc formate monohydrate in 1:2 ratio in toluene leads to the formation of bis(2-ethylimidazole)bis(formato)zinc(II)-water (1/1), [Zn(N2H8C5)2(OCHO)2]·H2O, 1 which has been characterized by several techniques, including elemental and thermal analyses, IR, 1HNMR and 13CNMR spectroscopies, single crystal X-ray diffraction and DFT studies. The results obtained show that this complex crystallizes in the orthorhombic crystal system of the Pbca space group, with cell parameters a = 14.7230(2) &Aring;, b = 7.3880(10) &Aring;, c = 29.0843(4) &Aring;, α = 90°, β = 90°, γ = 90°, V = 3163.73 &Aring;3 and Z = 8. The zinc center is bound to two molecules of 2-ethylimidazole, two formate molecules in a tetrahedral coordination geometry. One water of crystallization is present in the coordination sphere of the compound. Its molecular crystalline structure is strengthened by O/N-H…O, O-H…π, O-H…H, C-H…O, H…π, π…O and π…π interactions. The optimized structure, frontier molecular orbitals, global reactivity descriptors, molecular electrostatic potential, natural bond orbitals and the Mulliken atomic charges were investigated through theoretical studies. 展开更多
关键词 ZINC Complex 2-Ethylimidazole Hydrogen BONDS THERMOGRAVIMETRIC Analysis 1HNMR 13CNMR x-ray THEORETICAL Studies
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Synthesis, Structural Characterization and DFT Studies of Silver(I) Complex Salt of Bis(4,5-dihydro-1<i>H</i>-benzo[g]indazole)
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作者 Tanyi Rogers Fomuta Golngar Djimassingar +3 位作者 Jean Ngoune Nana Odette Ngnabeuye Jean Jacques Anguile Justin Nenwa 《Crystal Structure Theory and Applications》 2017年第2期11-24,共14页
A new silver complex salt [Ag(N2C11H10)2]NO3 (where N2C11H10 = 4,5-dihydro-1H-benzo[g]indazole), has been synthesized and characterized by elemental and thermal analyses, IR and 1HNMR spectroscopies, single crystal X-... A new silver complex salt [Ag(N2C11H10)2]NO3 (where N2C11H10 = 4,5-dihydro-1H-benzo[g]indazole), has been synthesized and characterized by elemental and thermal analyses, IR and 1HNMR spectroscopies, single crystal X-ray structure determination and DFT studies. Its molecular structure comprises of a silver center coordinated to two nitrogen atoms from two 4,5-dihydro-1H-benzo[g]indazole molecule giving rise to a cationic complex entity, [Ag(N2C11H10)2]+ with as counter ion. The bulk structure is consolidated by N–H…O, C–H…π, Ag…π and Ag…O intermolecular interactions, thus generating a pseudo-helical network. The optimized structure, frontier molecular orbitals (HOMO and LUMO) and global reactivity descriptors were investigated by performing DFT calculations. 展开更多
关键词 SILVER Complex Salt 4 5-dihydro-1H-benzo[g]indazole Hydrogen Bonds THERMOGRAVIMETRIC Analysis 1HNMR x-ray DFT Studies
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微种植体辅助整体内收上前牙段的头影测量 被引量:4
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作者 张华 麦志辉 +2 位作者 卢红飞 艾虹 文冲 《暨南大学学报(自然科学与医学版)》 CAS CSCD 北大核心 2011年第6期632-636,共5页
目的:研究微种植体支抗在矫治上颌前突病例中整体内收上前牙段的应用。方法:选择5例上颌前突患者,拔除第二前磨牙,采用直丝弓矫治技术,辅以微种植体支抗同时整体内收前牙段(6个前牙及2个第一前磨牙),通过X线头影测量分析,观察矫治前后... 目的:研究微种植体支抗在矫治上颌前突病例中整体内收上前牙段的应用。方法:选择5例上颌前突患者,拔除第二前磨牙,采用直丝弓矫治技术,辅以微种植体支抗同时整体内收前牙段(6个前牙及2个第一前磨牙),通过X线头影测量分析,观察矫治前后上颌骨软硬组织的变化。结果:上颌骨的变化轻微;切牙平均内收(4.6±1.5)mm,压低(0.8±1.1)mm,根尖后移(1.7±1.4)mm,切牙与腭平面的夹角减少(6.8±3.5)度;支抗磨牙水平前移(0.5±0.3)mm,没有出现明显的颌向伸长;上唇突度减少(2.0±0.9)mm,鼻唇角增大(3±2.4)度。结论:微种植体能提供稳定的支抗,同时整体内收上前牙段,最大限度避免支抗的丧失,改善上唇突度。 展开更多
关键词 X线头影测量 微种植体支抗 整体内收
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恒牙初期正常软组织侧貌分析 被引量:10
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作者 袁东辉 左艳萍 +1 位作者 王天轶 李向飞 《中国美容医学》 CAS 2007年第1期95-98,共4页
目的:通过X线头影测量,探讨恒牙初期青少年正常软组织侧貌特征及软组织的变异性。方法:选择恒牙初期正常青少年70名,分为侧貌协调组和侧貌欠协调组,确定22项常用的软组织侧貌测量指标。结果:上下唇E线距(Ls-E、Li-E)、上下唇突角(Ls... 目的:通过X线头影测量,探讨恒牙初期青少年正常软组织侧貌特征及软组织的变异性。方法:选择恒牙初期正常青少年70名,分为侧貌协调组和侧貌欠协调组,确定22项常用的软组织侧貌测量指标。结果:上下唇E线距(Ls-E、Li-E)、上下唇突角(LsNsLi)、上唇颏突角(LsNsPg')、H角5项软组织测量值两组间的差异有统计学意义(P<0.05)。侧貌协调组的测量值均小于欠协调组。结论:恒牙初期正常软组织侧貌在上下唇突度上有一定变异性。面型与型存在着不一致性。 展开更多
关键词 软组织侧貌 正常[牙合] X线头影测量分析
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