Lanthanide/zinc centered photoactive hybrids with functional sulfonamide linkage: Coordination bonding assembly,characterization and photophysical properties

In this paper, two novel kinds of organic–inorganic monomer, SUA-APEMS and SUA-APS, have been achieved by modifying 5-sulfosalicylic acid (SUA) with 3-aminopropyl-methyl-diethoxylsilane (APEMS) and 3-aminopropyl trimethoxysilane (APS). These two organic–inorganic monomers were used as multi-functional bridged components, which can coordinate to metal ions (Tb³⁺/Eu³⁺/Zn²⁺) with carbonyl groups, strongly absorb ultraviolet and effectively transfer energy to metal ions through their triplet excited state, as well as involve in the sol–gel process with inorganic host precursor tetraethoxysilane (TEOS), resulting two series of molecular hybrid materials (named as SUA-APEMS/APS-RE) with double chemical bond (RE(Zn)–O coordination bond and Si–O covalent bond). The effective intra-molecular energy transfer process gives rise to the characteristic emission of metal ions and the chemical bond make the hybrid materials owning better properties.     

无线光通信系统大气信道特性的分析研究

介绍了大气激光通信的基本原理、关键技术和应用领域;分析了大气信道对无线光通信系统的影响,着重分析大气的衰减效应和大气的湍流效应;指出在我国特定地区进行大气信道测试的必要性;最后介绍和分析了大气信道特性的主要测试方法.     

浅谈电网谐波

对电网中谐波大量涌现原因及出现干扰问题应采取的相关抑制措施。     

Luminescence properties of [Ru(bpy)2MDHIP]2+ modulated by the introduction of DNA,copper(II) ion and EDTA

The luminescence properties of [Ru(bpy)₂MDHIP]²⁺ (bpy = 2,2′-bipyridine, MDHIP = 2,4-dihydrophenyl-imidazo[4,5-f][1,10]phenanthroline) in the absence and presence of DNA modulated by the introduction of Cu²⁺ ion and EDTA have been investigated. It is found that the ruthenium(II) complex can insert and stack between the base pairs of calf thymus DNA with MDHIP ligand, and the intramolecular hydrogen bond is located inside of the DNA. The presence of DNA can enhance the luminescence intensities of [Ru(bpy)₂MDHIP]²⁺ both in buffer solution and on an ITO surface. Moreover, the luminescence intensities of [Ru(bpy)₂MDHIP]²⁺ and DNA-bound [Ru(bpy)₂MDHIP]²⁺ are quenched by Cu²⁺, and next recovered by the addition of EDTA. The repetitive luminescence-modulations have been achieved through the introduction of equimolar Cu²⁺ and EDTA, respectively. In addition, it becomes evident that the number of luminescence-modulation cycles for [Ru(bpy)₂MDHIP]²⁺ in the absence and presence of DNA is influenced by the cumulative concentrations of CuEDTA, generated successively by the strong coordination of Cu²⁺ to EDTA.     

Synthesis, structure and magnetic properties of two new azido-Co(II) coordination architectures: from ferromagnetic coupling to single-chain-magnets

Two new azido-Co(II) complexes with pyrazine carboxylato ligands, [Co(N(3))(L)·H(2)O](n) (L = pyrazine-2-carboxylato) (1) and [CoNa(N(3))(2)(L)](n) (2), have been obtained by carefully tuning the Co(II):N(3)(-) ratio. Here we present the structural and magnetic characterization of these new species. Modulation of the coordination environment of Co(II) leads to a variation of the magnetic properties of the obtained compounds. Complex 1 exhibits ferromagnetically coupled [Co(2)] units that form the rungs of the ladder with a nearly negligible coupling between these units, while complex 2 is a 2D arrangement of 1D Co(II) single-chain magnets.     

Morphology controllable synthesis and luminescence properties of NaLa(WO4)2:Eu microcrystals

NaLa(WO₄)₂:Eu microcrystals with shapes of four-arris shuttle, quadrangled star, and quadrangled dendrite were hydrothermally synthesized at 180 °C for 16 h. The concentration of the reactants and cetyltrimethyl ammonium bromide (CTAB) influenced the morphologies of the products. As La(NO₃)₃, Na₂WO₄ and CTAB was 0.375, 1.0, and 1.0 mmol, respectively, four-arris shuttle was obtained. As the concentration of the reactants doubled and the amount of CTAB ranged from 0.4 to 2.0 mmol, quadrangled dendrite, quadrangled star and four-arris shuttle were prepared, respectively. Luminescence intensity measurement of the three morphologies of NaLa(WO₄)₂:Eu showed that quadrangled dendrite was the strongest and four-arris shuttle was the lowest.     

Toxicokinetics and the related metabolites in rainbow trout (Oncorhynchus mykiss) after exposure to decabromodiphenyl ether

Decabromodiphenyl ether (BDE209) is poorly absorbed by mammals, and little information is available on the toxicokinetics of BDE209 and its metabolites in fish. In the present study, rainbow trout (Oncorhynchus mykiss) were administered to 100 ng/g and 500 ng/g body wet weight of BDE209 via a single intraperitoneal injection and parent BDE209 and its metabolites were sequentially monitored for 28 days. The results showed that toxicokinetic profiles of BDE209 could be described by the one-compartment model. In the higher dose group (500 ng/g wet weight), the calculated half-life (t _1/2) and elimination rate (k _e) were 17.7 d and 0.039/d in the liver, and 100.3 d and 0.007/d in the muscle, respectively. Three major methoxylated brominated diphenyl ethers (MeO-BDEs) were detected with 2,2′,4,4′-tetrabromo-5-methoxydiphenyl ether (5-MeO-BDE47) being detected in all tissue samples. There was no significant temporal change of 5-MeO-BDE47 concentration in the muscle, whereas an exponential increase was observed in the liver. Therefore, the metabolism rate of BDE209 depended on the administered dose. BDE209 was hardly accumulated in the muscle of rainbow trout, while the liver was a primary metabolic organ. MeO-BDEs were formed via metabolism of BDE209, which probably played a significant role in fish toxicology as a potential indicator.     

N,N′‐Diethyl‐4‐nitrobenzene‐1,3‐diamine, 2,6‐bis(ethylamino)‐3‐nitrobenzonitrile and bis(4‐ethylamino‐3‐nitrophenyl) sulfone

N,N′‐Diethyl‐4‐nitrobenzene‐1,3‐diamine, C₁₀H₁₅N₃O₂, (I), crystallizes with two independent molecules in the asymmetric unit, both of which are nearly planar. The molecules differ in the conformation of the ethylamine group trans to the nitro group. Both molecules contain intramolecular N—H...O hydrogen bonds between the adjacent amine and nitro groups and are linked into one‐dimensional chains by intermolecular N—H...O hydrogen bonds. The chains are organized in layers parallel to (101) with separations of ca 3.4 Å between adjacent sheets. The packing is quite different from what was observed in isomeric 1,3‐bis(ethylamino)‐2‐nitrobenzene. 2,6‐Bis(ethylamino)‐3‐nitrobenzonitrile, C₁₁H₁₄N₄O₂, (II), differs from (I) only in the presence of the nitrile functionality between the two ethylamine groups. Compound (II) crystallizes with one unique molecule in the asymmetric unit. In contrast with (I), one of the ethylamine groups, which is disordered over two sites with occupancies of 0.75 and 0.25, is positioned so that the methyl group is directed out of the plane of the ring by approximately 85°. This ethylamine group forms an intramolecular N—H...O hydrogen bond with the adjacent nitro group. The packing in (II) is very different from that in (I). Molecules of (II) are linked by both intermolecular amine–nitro N—H...O and amine–nitrile N—H...N hydrogen bonds into a two‐dimensional network in the (10) plane. Alternating molecules are approximately orthogonal to one another, indicating that π–π interactions are not a significant factor in the packing. Bis(4‐ethylamino‐3‐nitrophenyl) sulfone, C₁₆H₁₈N₄O₆S, (III), contains the same ortho nitro/ethylamine pairing as in (I), with the position para to the nitro group occupied by the sulfone instead of a second ethylamine group. Each 4‐ethylamino‐3‐nitrobenzene moiety is nearly planar and contains the typical intramolecular N—H...O hydrogen bond. Due to the tetrahedral geometry about the S atom, the molecules of (III) adopt an overall V shape. There are no intermolecular amine–nitro hydrogen bonds. Rather, each amine H atom has a long (H...O ca 2.8 Å) interaction with one of the sulfone O atoms. Molecules of (III) are thus linked by amine–sulfone N—H...O hydrogen bonds into zigzag double chains running along [001]. Taken together, these structures demonstrate that small changes in the functionalization of ethylamine–nitroarenes cause significant differences in the intermolecular interactions and packing.     

Poly[bis(μ‐4‐benzoyl‐1‐isonicotinoylthiosemicarbazide‐κ2N:S)dichloridocadmium(II)]

The asymmetric unit of the title complex, [CdCl₂(C₁₄H₁₂N₄O₂S)₂]_n, consists of one Cd^II ion located on the crystallographic inversion centre, one 4‐benzoyl‐1‐isonicotinoylthiosemicarbazide ligand and one chloride ligand. The central Cd^II ion adopts a distorted octahedral coordination geometry formed by two pyridyl N atoms of two ligands, two S atoms of two other ligands and two chloride ligands. The thiosemicarbazide ligands act as bridges, linking the metal ions into a two‐dimensional layered structure parallel to the bc plane. Intermolecular N—H...O hydrogen bonds and C—H...π interactions exist between adjacent layers.     

抽提物对生物质热裂解机理的影响研究

利用惰性溶剂从生物质中提取得到相应抽提物,在热重红外联用仪上研究了抽提物的热裂解行为,并探讨了其对生物质热裂解的影响。结果表明,因不同种类生物质中木质素结构单元中紫丁香基和愈创木基数量不同,从而导致抽提物成分存在差异,相应的热裂解产物分布也不一致。水曲柳抽提物因含有较多的酚类物质而在热解高温段生成了甲醇和甲烷。相比于原样,抽提残渣反应活化能增加,且主要产物析出时间提前,同时酸类物质和直链烷烃析出量减少,而水、CO2、CO和醛类物质的产量则有所增加。