Isolation and Crystallographic Characterization of Tm3N@D2 (35)-C88

Tm₃N@D₂(35)-C₈₈ has been prepared by vaporization of graphite rods doped with Tm₂O₃, graphite powder, and iron nitride in a Krätschmer-Huffman arc-discharge fullerene generator and isolated by high pressure liquid chromatography. A single crystal X-ray diffraction study reveals the dimensions of the D₂(35)-C₈₈ cage and the positioning of the Tm₃N unit inside.     

曝光量对DCG中Cr2P_(3/2)XPS谱的影响的研究

通过对不同曝光量的重铬酸盐明胶(DCG)中的Cr2P3／2XPS（X射线光电子能谱）的规定发现，Cr2P3／2XPS谱随曝光量呈规律性的变化：在0～195mJ／cm2曝光量范围内，它的1／5高宽度（FWFM，即：thefullwidthatfifthmaximum）和576．4eV附近的峰的相对强度先随曝光量增加而增大，到达极大值后又随曝光量的增加而减小；相反，它的579．4eV和577．4eV附近的两个峰的相时强度却是先随曝光量的增加而减小，达到极小值后又随曝光量的增加而增大。对这些不同曝光量的DCG膜定性地水洗处理后，曝光量为130mJ/cm2的全息图最均匀、明亮；曝光量为195mJ／cm2的全息图衍射效率很低，且有残余黄褐色。根据这些实验结果和固态膜反应的特点，就曝先对DCG微观结构引起的变化作了分析，确定出了贡献各峰的化合物状态并科学准确地找到了Cr2P3／2XPS谱随曝光量成规律性变化的本质原因是作为潜影中心的二氧化铬（576．4eV附近的铬）严格地受曝光量的制约。这个结论的得出，为制作理想的全息图选择合适的曝光量提供了理论依据。即：576．4eV附近的峰有最大相对强度的曝光量为最佳曝光量。     

Superconductivity in alkali-doped fullerides with wood’s metal and heterofullerides with two different alkali metals A(1)A(2)MC60

Abstract

Here we report our experimental data on the synthesis and investigation of superconductivity in fullerides and heterofullerides synthesized by different methods and also doped by alloys with low melting temperature T_m: Wood’s metal (W – Sn,Pb,Bi,Cd; T_m?=?65°С), alloy Y (Y - Bi,Sn.Pb,In,Cd,Tl; Т_m?=?41.5°С) and Tl doped heterofullerides with two different alkali metals – ACsTlC₆₀ (A?=?K, Rb). We found superconductivity in heterofullerides K₂W₁C₆₀ (T_c?=?16 K), Rb₂W₁C₆₀ (T_c?=?8 K) and K₂Y₁C₆₀ (T_c?=?8 K). Also synthesized heterofullerides with Cesium KCsTlC₆₀ (Т_с?=?21.7 K) and RbCsTlC₆₀ (Т_с?=?26.4 K) are superconductors.     

Neutron bombardment of boron carbide B12C3: A FT-IR,calorimetric (DSC) and ESR study

Boron carbide B₄C or, which is the same, B₁₂C₃, was neutron-bombarded at four different doses, namely at 1.09, 2.19, 3.28 and 4.38 × 10¹⁶ n cm^?2. The radiation-damage was studied by FT-IR, ESR (Electron Spin Resonance) and by DSC (Differential Scanning Calorimetry). It is shown that both FT-IR and ESR are useful techniques to monitor the radiation-damage level introduced in B₁₂C₃, with the ESR characterized by a higher sensitivity level than FT-IR. Thermal annealing of the neutron-treated B₁₂C₃ from room temperature to 630°C permits to measure the release of the stored Wigner energy which was found comprised between 0.55 meV/atom at the lowest neutron dose to 2.29 meV/atom at the highest neutron dose employed. The values of Wigner energy measured on B₁₂C₃ were comparable to those measured on fullerenes and graphite flakes at the same dose level. However, the thermal annealing of neutron-treated B₁₂C₃ does not lead to the complete restoration of the pristine chemical structure before irradiation.     

[Cu(1,4-C4H12N2)2(ClO4)2]n(H2O)2n,a novel butane-1,4-diamine-bridged two-dimensional copper(II) square network: Synthesis,structure, and magnetic properties

A novel butane-1,4-diamine-bridged copper(II) compound was synthesized via solvent diffusion route with high yield. Each copper is coordinated by four butane-1,4-diamine ligands, each of which in turn links with two copper atoms to form a two-dimensional (2D) square network. Interestingly, the title compound features a cross-linking rhombic channel (ca. 5.06 × 14.73 Å) parallel to the crystallographic b axis. And magnetic result measured indicates the presence of localized unpaired electrons in the structure and thus the cupric Cu(II) state.     

Synthesis and crystal structures of a new (2,3-(CH3)2C6H3NH3)H2XO4 (X=P,As)

The aim of encapsulation of 2,3-dimethylanilinium cation in (H₂XO₄)_n polymeric anion chains is to build acentric frameworks that are efficient for non-linear optical (NLO) applications. The synthesis and structures of two new inorganic–organic NLO crystals with general formula (2,3-(CH₃)₂C₆H₃NH₃)H₂XO₄ (X=P, As) are reported. The magnitude of their second harmonic generations (SHG) responses was found to be between the KDP and urea. They crystallize with monoclinic unit-cells and are isotopic. We have determined the structure of phosphoric salt. The following unit-cell parameters were found: a=8.866(3) Å, b=5.909(6) Å, c=10.644(5) Å, β=112.44(1)°, V=515.5(5) Å³ and D_X=1.412 g cm⁻³. The space group is P2₁ with Z=2. The structure was refined with R=0.041 (R_w=0.057) for 1652 reflections with I≥3σ(I). It exhibits infinite (H₂PO₄)_nⁿ⁻ chains. The organic groups (2,3-(CH₃)₂C₆H₃NH₃)⁺ are anchored between adjacent polyanions through multiple hydrogen bonds. Chemical preparation, crystal structure, calorimetric and spectroscopic investigation are described.     

Synthesis and characterization of a new monophosphate (5-Cl-2,4-(OCH3)2C6H2NH3)H2PO4

Chemical preparation, crystal structure and NMR spectroscopy of a new organic cation 5-chloro(2,4-dimethoxy)anilinium monophosphate H₂PO₄ are given. This new compound crystallizes in the monoclinic system, with the space group P2₁/c and the following parameters: a = 5.524(2) Å, b = 9.303(2) Å, c = 23.388(2) Å, β = 90.66(4), V = 1201.8(2) Å³, Z = 4 and D_x = 1.573 g cm⁻³. Crystal structure has been determined and refined to R = 0.031 and R_w = 0.080 using 1702 independent reflections. Structure can be described as an infinite (H₂PO₄)_nⁿ⁻ corrugated chains in the a-direction. The organic groups (5-Cl-2,4-(OCH₃)₂C₆H₂NH₃)⁺ are anchored between adjacent polyanions through multiple hydrogen bonds. This compound is also investigated by IR, thermal, and solid-state, ¹³C, ³¹P MAS NMR spectroscopies.     

非线性光学晶体MnHg(SCN)4(C2H6SO)2的热学和光学性质的测定

制备了一种新型非线性光学晶体二甲亚砜合硫氰酸汞锰(分子式MnHg(SCN)4(C2H6SO)2,简称MMTD).用热重法、差热分析法、差示扫描量热法、热机械分析法、分光光度法和红外光谱研究了它的热学和光学性质.MMTD晶体具有较好的物理化学稳定性.在27℃时,它的比热为699.5 J/mol·℃.晶体的热膨胀系数为α1=5.33×10-5/℃,α2=4.51×10-5/℃,α3=3.10×10-5/℃.MMTD晶体的截止波长为375nm;透光波段为375-2560 nm.MMTD晶体在标准紫光波长404nm的透过率为44.18%,高于硫氰酸汞锰(MMTC)晶体.     

Synthesis and photoluminescence of new phosphors M2(Mg, Zn)Si2O7:Mn (M = Ca, Sr, Ba)

New phosphors M₂(Mg, Zn)Si₂O₇:Mn²⁺ (M = Ca, Sr, Ba) were prepared by sol-gel process, and their luminescent properties in ultraviolet and vacuum ultraviolet region were investigated. The results showed that the (Ca, Sr, Ba)₂MgSi₂O₇:Mn²⁺ samples did not emit any visible light; the Sr₂ZnSi₂O₇:Mn²⁺ and Ca₂ZnSi₂O₇:Mn²⁺ samples showed green light. The Ba₂ZnSi₂O₇:Mn²⁺ sample mainly showed green light under 254 nm excitation and red light under 147 nm excitation. The different emission was due to the Mn²⁺ ions occupied different sites, which were excited selectively. Among the three phosphors Sr₂ZnSi₂O₇:Mn²⁺ showed the highest green emission intensity, and its decay time was shorter than that of Zn₂SiO₄:Mn²⁺ under 147 nm excitation.     

Synthesis and application of a novel mesoporous SBA-15 sorbent functionalized by 2,4 dinitrophenylhydrazine (DNPH) for simultaneous removal of Pb(II), Cr(III), Cd(II) and Co(II) from aqueous solutions: Experimental design,kinetic, thermodynamic,and isotherm aspects

Heavy metal cations are the most common group of pollutants which significantly contribute to the pollution of aquatic systems. Among the heavy metal cations, lead, chromium, cadmium and cobalt are the most abundant cations present in wastewaters. In this work, a novel sorbent was synthesized via functionalization of chloro-mesoporous SBA-15 with 2,4- dinitrophenylhydrazine. The adsorbent was identified by various characterization techniques and then was used for adsorption of Pb(II), Cr(III), Cd(II), and Co(II). and then the response surface methodology was employed to study the influence, and interaction of different parameters. According to the results, the optimized adsorption capacity of 242.50, 214.72, 187.86, 166.46 mg/g was obtained respectively for the studied cations. furthermore, the sorption of cations was fast and the process achieve to equilibrium within 23.65, 20.31, 24.05 min for Pb(II), Cr(III), Cd(II) and within 19.88 min for Co(II). The adsorbent regenerated by a mixture of nitric acid and methanol could be recycled without losing a remarkable amount of capacity. The results analyzed with various isotherm models were best conformed to the Langmuir model.     

Black Phosphorus,a Rising Star 2D Nanomaterial in the Post‐Graphene Era: Synthesis,Properties, Modifications,and Photocatalysis Applications

Semiconductor photocatalysis, a sustainable and renewable technology, is deemed to be a new path to resolve environmental pollution and energy shortage. The development of effective photocatalysts, especially the metal‐free photocatalysts, is a critical determinant of this technique. The recently emerged 2D material of black phosphorus with distinctive properties of tunable direct bandgap, ultrahigh charge mobility, fortified optical absorption, large specific surface area, and anisotropic structure has captured enormous attention since the first exfoliation of bulk black phosphorus into mono‐ or few layered phosphorene in 2014. In this article, the state‐of‐the‐art preparation methods are first summarized for bulk black phosphorus, phosphorene, and black phosphorus quantum dot and then the fundamental structure and electronic and optical properties are analyzed to evaluate its feasibility as a metal‐free photocatalyst. Various modifications on black phosphorus are also summarized to enhance its photocatalytic performance. Furthermore, the multifarious applications such as solar to energy conversion, organic removal, disinfection, nitrogen fixation, and photodynamic therapy are discussed and some of the future challenges and opportunities for black phosphorus research are proposed. This review reveals that the rising star of black phosphorus will be a multifunctional material in the postgraphene era.     

Interaction of U(VI), Np(VI), and Pu(VI) with picolinic (2-pyridinecarboxylic) acid: Complexation in aqueous solutions and synthesis, spectra, and thermal properties of complexes [CH6N3][AnO2(C6H4NO2)3] (An = U, Np, Pu)

Complexation of actinides(VI) (U, Np, Pu) with picolinic acid C₆H₅NO₂ (HPic) in solution was studied by spectrophotometry. In particular, data on the Np(VI) complexation were obtained for the first time. The complexes [AnO₂(HPic)]²⁺, [AnO₂(Pic)]⁺, [AnO₂(Pic)₂], and, presumably, [AnO₂(HPic)(Pic)]⁺, and also mixed picolinate-hydroxide complexes can exist in the solution under different conditions. The stability constants of the complexes were estimated. A series of crystalline actinide(VI) picolinate complexes Gu[AnO₂(Pic)₃] (An = Np, Pu; Pic is picolinate ion, Gu is guanidinium ion) were synthesized, and their structure was determined. The spectra and thermal behavior of the complexes are discussed.     

KREP2Se6 (RE = Sm,Gd, Tb): The First Rare-Earth Selenophosphates with Remarkable Nonlinear Optical Activities Realized by Synergistic Effect of RE- and P-Based Motifs

Rare-earth (RE) chalcogenides have been extensively studied as infrared nonlinear optical (NLO) materials because of their nice integrated performances; however, very few RE chalcophosphates are involved for this topic. Here, three quaternary RE selenophosphates, KSmP₂Se₆ (1), KGdP₂Se₆ (2), and KTbP₂Se₆ (3), are profoundly studied for their NLO potentials. Their noncentrosymmetric P21 structures feature RESe8-bicapped trigonal prisms and ethane-like [P₂Se₆]₄− dimers built {[REP₂Se₆]−}∞ layers. As the first studied NLO-active RE selenophosphates, 1–3 exhibit second harmonic generation (SHG)responses ≈0.34–1.08 × AgGaS₂ at 2.10 µm and laser-induced damage thresholds (LIDTs) ≈1.43–4.33 × AgGaS₂, and they all show phase-matchable behaviors, indicating their wonderful balanced NLO properties. Theoretical calculations demonstrate that the synergistic effect between RESe₈ and P₂Se₆ units makes the major contribution to the SHG responses.     

YBCO超导薄膜进氧脱氧过程的原位X射线衍射研究

用原位X射线衍射法研究了磁控溅射c取向YBa2 Cu3 O6+x/SrTiO3 (YBCO/STO)优质超导外延膜在 3 2 5℃氧气中的进氧过程和氮气中的脱氧过程。研究表明 ,薄膜的进氧和脱氧过程快慢相当 ,进脱氧过程都由氧扩散控制。     

A new nanocomposite superionic system (CdHgI4/HgI2): Synthesis,characterization and experimental investigation

In this paper, we report a new and convenient synthetic method based on a reaction in an aqueous system, which can produce a new nanocomposite superionic system (CdHgI₄/HgI₂) at 70 °C for 20 min. It is the first time that these nanocomposites are synthesized. In this work, we have chosen lithium iodide, cadmium and mercury acetate as starting reagents. First, an aqueous solution of cadmium acetate, surfactant and lithium iodide is obtained. Second, an aqueous solution of mercury acetate and lithium iodide is prepared. Then obtained solution is added to the first solution. The effects of the surfactant and mole ratio of Cd:Hg have been optimized to achieve the best products on morphology and purity. When the molar ratio of Cd:Hg is 1:1, in the absence of surfactant also in the presence of CTAB and Triplex, pure aggregated nanostructures are formed. The nanocomposites are characterized using scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD) and cyclic voltammetry (CV). The electrical conductivity measurement carries out at frequencies of 100 Hz, 1000 Hz, 10 kHz and 100 kHz in the temperature range 70–140 °C. Results show that the best morphology and purity have been achieved in the absence of surfactant, in 1:1 ratio of precursors.     

苯甲酸系列邻菲啰啉硝酸根稀土四元混配配合物的合成、表征和抗菌活性研究

在酸性介质 ,乙醇 /水混合溶剂中合成得到了四元混配配合物 [Ln(C6 H5COO) 2 (NO3)(phen) ]2 (Ln =La ,Ce ,Pr ,Nd ,Sm ,Eu ,Gd ,Er ,Tm)和 [Nd(x MBA) 2 (NO3) (phen) ]2 (x =o、p、m) (MBA =甲基苯甲酸 )。用元素分析、IR和UV方法对配合物进行了表征 ,并对配合物的抗枯草杆菌、大肠杆菌、金黄色葡萄球菌、酵母菌、白念珠菌、和霉菌的性能进行了研究。