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91.
Guo Qiang HU Wen Long HUANG Hai WANG 《中国化学快报》2005,16(10):1309-1312
6/3-(4-Chlorophenyl)-s-triazolo[3, 4-b][1, 3, 4]thiadiazoles (2,a-e) and (Sa-e) were synthesized respectively by intermolecular cyclization of 5-aryl / 4-chlorophenyl-4-amino-3- mercapto-1, 2, 4-triazoles (la-e) and (4) with 4-chlorobenzoic acid / aryl acids, which were condensed with piperazine under phase transfer catalyst TBAB to yield the corresponding free bases of monopiperazine derivatives and followed to form water-soluble salts (3a-e) and (6a-e) with hydrochloric acid in good yields. The in vitro biological results showed that piperazine group conjugated with the above fused heterocycles played an important role in antibacterial activity. The structures of novel compounds were confirmed by IR, 'H NMR, MS and elemental analysis. 相似文献
92.
Tadahito Takahashi Michihiro Yamaguchi 《Journal of inclusion phenomena and macrocyclic chemistry》1991,10(2):283-297
The formation of a complex between a swelling clay mineral and griseofulvin (GF), a poorly water-soluble drug, was examined. A strong host-guest interaction between the neutral drug molecules and the clay mineral was observed not only in the solid state but also in aqueous dispersion. The powder X-ray diffraction patterns revealed the disappearance of a crystalline phase of GF through host-guest interaction for samples having low GF contents. The complex formation was confirmed to be due to monolayer adsorption on the basis of quantitative thermochemical analyses. The strong interaction between GF and the clay was also detected when the complex powder was dispersed in an aqueous medium on the basis of the intensity changes of from free GF solution in CD and fluorescence spectra as compared with those observed for the free GF solution. 相似文献
93.
E. Paetzold G. Oehme C. Fischer M. Frank 《Journal of molecular catalysis. A, Chemical》2003,200(1-2):95-103
The rhodium-catalyzed hydroformylation of 1-dodecene was investigated with a series of sulfonated water-soluble phosphine ligands at a pressure of 60 bar CO/H2 and a temperature of 120 °C. Seven different groups of water-soluble phosphines were used for our investigations. We established an optimized ligand/rhodium ratio of 5 for the phosphines 1a, [Ph2P(CH2)2S(CH2)2SO3Na], and 1b, [Ph2P(CH2)2S(CH2)3SO3Na]. The utilized arylphosphino-thioether-alkylsulfonates formed with Rh(I) compounds highly active catalysts which could be recycled. The addition of detergents speeds up the hydroformylation reaction, but disturbs the phase separation (recycling). The best promotion effect and the smallest negative influence on phase separation gave polyoxyethylene–polyoxypropylene–polyoxyethylene triblock co-polymers. The ratio of 1-dodecene/rhodium could be increased up to 10.000 and we achieved turnover numbers (TONs)>50.000 without any surfactant and TONs of about 65.000 in presence of the co-polymers owing to the recycling on the catalytic system. 相似文献
94.
Ineke Joosten Maarten R. van Bommel Regina Hofmann-de Keijzer Hans Reschreiter 《Mikrochimica acta》2006,155(1-2):169-174
Due to the special conditions in the Bronze Age and Hallstatt Period salt-mines of Hallstatt, Austria, a large number of archaeological
textile fragments, dated from 1400 to 400 BC, can be found. Textiles of good condition from these periods are quite unique.
The fibres are identified as wool and most of the fragments still have colours i.e. yellow, green, olive-green, brown, blue
and black. To obtain information about the dyeing techniques used in this period, dyestuffs analyses are performed by high
performance liquid chromatography coupled to photo diode array detection (HPLC-PDA) and mordant analysis by scanning electron
microscopy with energy dispersive X-ray spectroscopy (SEM/EDS). In addition, the condition of the textile fibres is assessed
by SEM. The analyses revealed that all textiles were dyed with plant dyes and insect dyes. The yellow plant dyes and the red
insect dyes are mordant dyes but the identification of mordants turned out to be difficult. SEM/EDS analyses of small uncontaminated
areas on the fibre showed that the elements aluminium, iron and copper are present in many samples. These elements could originate
from a mordant or from the mine. The condition of the fibres was assessed by the presence of the characteristic scales on
the wool, tears, cuts and particles from the mine. It was found that a relation exists between the copper content of the fibres
and their condition. Degraded fibres contain more copper. Black textile fragments which are most possibly coloured by iron
gall-black show as well degradation phenomena. 相似文献
95.
The main results obtained by studying hydroformylation of olefins on polymeric rhodium-containing catalysts are reviewed. Different types of N-containing polymeric ligands capable of hydroformylating under conditions of heterogeneous catalysis are considered. Possibilities of using water-soluble polymers containing quaternary ammonium groups are shown. The data on the influence of a polymeric matrix on the catalytic properties of the rhodium catalyst of olefin hydroformylation are presented.__________Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 2346–2351, November, 2004. 相似文献
96.
Melvyn Rowen Churchill Ronald F. See Robert L. Rominger Jim D. Atwood 《Journal of chemical crystallography》1996,26(11):747-752
The title compound crystallizes in the centrosymmetric triclinic space group
withZ=4. The crystallographic asymmetric unit contains two independent cations; interatomic distances within these include P=O=1.47(1) and 1.47(1) Å, P–C6H5=1.78(2)–1.81(1)Å and P–CH2CH2NMe3
+=1.80(1) and 1.81(1) Å. The phosphine oxide moiety is involved in intermolecular hydrogen bonding ()...H–C, with O...H2.42Å) and the iodide is involved in I...H–C contacts with I...H3.10Å. 相似文献
97.
QIN ChuanJiang TONG Hui & WANG LiXiang State Key Laboratory of Polymer Physics Chemistry Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun China 《中国科学B辑(英文版)》2009,(6)
An anionic water-soluble polyfluorene derivative, poly(9,9-bis(6′-phosphatehexyl)fluorene-alt-1,4-pheny lene) sodium salt (PFHPNa), was synthesized by Suzuki coupling reaction in DMF/water. Polymer PFHPNa was well soluble in water with a strong blue fluorescence emission. Effect of the side chain length on fluorescence sensory properties was studied by comparing quenching efficiencies toward different quenchers of PFHPNa with a reported polymer poly(9,9-bis(3′-phosphatepropyl)fluorene-alt-1,4-phenylene) sod... 相似文献
98.
This paper reviews our work on the fundamental principles of high gravity controlled precipitation (HGCP) technology, and its applications in the production of drug nenoparticles, which was carded out in a rotating packed bed (RPB). Several kinds of drug nanoparticles with narrow particle size distributions (PSDs) were successfully prepared via HGCP, including the 300-nm Cefuroxirne Axetil (CFA) particles, 200-400-nm cephradine particles, 500-nm salbutamol sulfate (SS) particles (100 nm in width), end 850-nm beclomethasone dipropionate (BDP) particles, etc. Compared to drugs available in the current market, all the drug nanoparticles produced by HGCP exhibited advantages in both formulation end drug delivery, thus improving the bioavailability of drugs. HGCP is essentially a platform technology for the preparation of poorly water-soluble drug nanoparticles for oral and injection delivery, and of inhalable drugs for pulmonary delivery. Consequently, HGCP offers potential applications in the pharmaceutical industry due to its cost-effectiveness, efficient processing end the ease of scaling-up. 相似文献
99.
利用在线监测仪测量了杭州市一次重灰霾过程(2017年12月29日至2018年1月3日)中PM2.5主要水溶性离子(Cl-、SO42-、NO3-、NH4+、Na+、Ga2+、Mg2+)及主要气态污染物(SO2、NO2、O3、NO、CO、HCl、NH3、HNO2、HNO3)的小时浓度。结合混合受体模型和国控监测分析,研究了2017年12月30-31日重灰霾事件的污染特征、来源和成因。研究结果表明:PM2.5浓度高达318 μg·m-3; NO3-/SO42-最大值为2.68,说明移动源污染是杭州市PM2.5形成的重要来源; PM2.5/CO最高达到0.19,说明二次细颗粒物对PM2.5贡献很大;NO3-、SO42-、NH4+的浓度总和占PM2.5平均浓度的64.3%,说明二次无机细颗粒物是杭州重灰霾形成的重要原因,且NO3-的贡献最大,占33.5%。混合受体模型分析显示,杭州市重灰霾污染的潜在源区主要位于安徽、江苏、河南、山东四省交界处,以及安徽省中东部、蚌埠、芜湖等工业污染较为严重的城市。夹杂着大量污染物的北方干冷空气远距离传输叠加部分局地源是杭州此次重雾霾形成的根本原因。因此,为了改善杭州市空气质量,不仅需控制当地的污染物排放,而且还需对整个长三角地区甚至跨区域采取大气联防联控策略。 相似文献
100.
水溶性茂钛配合物的表征及其在芳香酸茂钛衍生物合成中的应用 总被引:2,自引:0,他引:2
二氯二茂钛与5-磺基水杨酸形成了较为稳定的水溶性配合物。由等摩尔系列 法确定了其组成为1:1,通过对含5-磺基水杨酸二茂钛配离子的不溶性配合物1的 结构分析表明,其中的羧基以双齿形式与钛配位,形成了四元环状结构。首次利用 该水溶性配合物在水相和两体系中得到了八种新的二茂钛芳香酸衍生物,为配合物 2 ~ 9。运用元素分析、IR及~1H NMR对它们的组成和结构进行了表征,结果表明 ,这八种配合物中羧基均以单齿形式与钛配位,且不含5-磺基水杨酸配体。 相似文献