Characterization of the Natural and Organomodified Clay Soil of Moukosso (Republic of Congo) by Dimethylsulfoxide: Application to the Adsorption of Lead (II) in Aqueous Solution

In this study, the authors characterized the raw clayey soil of Moukosso and modified by dimethylsulfoxide (DMSO) by several analytical methods, namely: X-ray diffraction (XRD), Fourier transform infrared (FTIR) and gravimetric thermal analysis (TGA). The cation exchange capacity (CEC) was also determined. Mineralogical analysis by XRD revealed the presence of muscovite (29.7%), kaolinite (8.9%), anatase (2.4%) and quartz (58.9%). The characterization of the organo-clay by infrared and by thermogravimetric analysis confirmed the intercalation of DMSO by the presence of vibration bands at 1008 cm-1 and 1070 cm-1 and a strong increase in the loss of mass. The cation exchange capacity of the raw material is 7.4 meq/100g. Rapid adsorption of Pb2+ ions was observed between 5 and 15 minutes of stirring time in both cases (raw clay and organomodified clay). The modeling of the isotherms by the models of Langmuir and Freudlich showed that these are of type S with a maximum amount of adsorption of 22.471 mg/g for the fine fraction and 41.493 mg/g for the clay intercalated with DMSO. Langmuir’s model best reproduces the experimental data of this study.

Study on the analysis and distribution of dimethylsulfoxide in the Jiaozhou Bay

A chemoreduction-purge-and-trap gas chromatographic method has been developed for the deter-mination of trace dimethylsulfoxide （DMSO） in seawater. In the analysis procedure, DMSO was first reduced to dimethylsufide （DMS） by sodium borohydride and then the produced DMS was analyzed using the purge-and-trap technique coupled with gas chromatographic separation and flame photometric detection. Under the optimum conditions, 97% DMSO was reduced in the standard solution samples with a standard deviation of 5% （n=5）. The detection limit of DMSO was 2.7 pmol of sulfur, corresponding to a concentration of 0.75 nmol/L for a 40 ml sample. This method was applied to determine the dissolved DMSO （DMSOd） and particulate DMSO （DMSOp） con- centrations in the surface seawater of the Jiaozhou Bay, and the results showed that the DMSOd and DMSOp concentrations varied from 16.8 to 921.1 nmol/L （mean：165.2 nmol/L） and from 8.0 to 162.4 nmol/L （mean： 57.7 nmol/L）, respectively. The high concentrations of DMSOp were generally found in productive regions. Consequently, a significant correlation was found between the concentrations of DMSOp and chlorophyll a, suggesting that phytoplankton biomass might play an important role in controlling the distribution of DMSOp in the bay. Moreover, in the study area, the concentrations of DMSOd were significantly correlated with the levels of DMS, implying that the production of DMSOd is mainly via photochemical and biological oxidation of DMS.

Preparation of Gd Co alloy in dimethylsulfoxide by electrodeposition method

Electrodeposition of Gd Co alloy film from dimethylsulfoxide (DMSO) electrolyte solutions has been investigated using cyclic voltammogram and potentiostatic technique. Potentiostatic depositions between -1.20 V and -2.70 V were applied to uncomplexed and complexed solution. The deposits obtained at potentials within -2.30～-2.70 V from complexed solutions are silver gray smooth films.

Electrochemical behaviors of Bi (Ⅲ) in dimethylsulfoxide

Cyclic voltammetry, chronoamperometry and chronopotentiometry were used toinvestigate the electrochemical behaviors of Bi(III) in Bi(NO_3)_3-LiClO_4-DMSO (dimethylsulfoxide)system on Pt and Cu electrodes. Experimental results indicated that the electroreducation of Bi(III)to Bi(0) was irreversible on Pt and Cu electrodes. The diffusion coefficient and electron transfercoefficient of Bi(III) in 0.01 mol.L^(-1) Bi(NO_3)_3-0.l mol.L^(-1) LiClO_4-DMSO system at 303 Kwere 1.75 X 10^(-6) cm^2.s^1 and 0.147 respectively.

Electrodeposition of Er-Ni Alloy Film in Dimethylsulfoxide

The cyclic voltammetry and chronoamperometry were used to investigate the electrochemical behaviors of Er(Ⅲ) and Ni(Ⅱ) in LiClO 4 DMSO(dimethylsufoxide) system on Pt and Cu electrodes. Experimental results indicated that the reduction of Er(Ⅲ) to Er and Ni(Ⅱ) to Ni were irreversible in one step on Pt and Cu electrodes. The diffusion coefficient and electron transfer coefficient of Er(Ⅲ) in 0.01 mol·L -1 ErCl 3 -0.1 mol·L -1 LiClO 4 DMSO system at 303K were 1.47×10 -10 m 2·s -1 and 0.108 respectively, and the diffusion coefficient and electron transfer coefficient of Ni(Ⅱ) in 0.01 mol·L -1 NiCl 2-0.1 mol·L -1 LiClO 4 DMSO system at 303K were 3.38×10 -10 m 2·s -1 and 0.160 respectively. The homogeneous, strong adhesive Er Ni alloy films with metallic lu- stre was prepared by potentiostatic electrolysis on Cu electrode in ErCl 3 NiCl 2 LiClO 4 DMSO system at -1.90～ -2.55 V (vs SCE).

Electrochemical Behavior of Yttrium in Dimethylsulfoxide

The relations between conductivity and temperature of YCl3-LiClO4-DMSO system were measured. The cyclic voltammetry, chronoamperometry, chronopotentiometry and X-ray diffraction were used to investigate the electrochemical behavior of Y3+ in YCl3-LiClO4-DMSO system on Pt and Cu cathodes. Experimental results indicate that the electroreduction of Y3+ to Y is irreversible in one step. The Y metal was prepared by potentiostatic electrolysis on Cu electrode in YCl3-LiClO4-DMSO system. The deposits composed of Y over 97% (mass fraction) were obtained. The diffusion coefficient and electron transfer coefficient of Y3+ in YCl3-LiClO4-DMSO system at 298 K are 3.22 x 10(-6) cm(2).s(-1) and 0.22, respectively.

Electrodeposition of Pr-Fe alloy films in urea-dimethylsulfoxide

Cyclic voltammetry and chronoamperometry were used to investigate theelectrochemical behavior of Pr^(3+) ions in a system of 0.01 mol centre dot dm^(-3) Pr(CH_3SO_3)_3 +0.01 mol centre dot dm^(-3) FeCl_2 + 3.0 mol centre dot dm^(-3) urea + DMSO on a R electrode. Someelectrochemical parameters were measured. Potentiostatic depositions between -1.6 and -2.4 V wereapplied to deposit Pr-Fe films in urea-DMSO mixed solution. The Pr content in the alloy films was inthe range of 34.89 wt. percent to 37.15 wt. percent. The Pr-Fe alloy films are proven to beamorphous by XRD (X-ray diffraction).

Synthesis and Crystal Structure of Co(DMSO)_2(H_2O)_2(SCN)_2 with One-dimensional Hydrogen-bonded Structure (DMSO = Dimethylsulfoxide)

The title complex Co（DMSO）2（H2O）2（SCN）2 has been prepared and structurally characterized. It crystallizes in monoclinic, space group P21/n with a= 5.1981（9）, b = 11.944（2）, c = 12.646（2） A,β = 98.686（2）°, V = 776.2（2） A^3, C6H16CoN2O4S4, Mr = 367.38, Z = 2, De = 1.572 g/cm^3, F（000） = 378 and μ（MoKa） = 1.646 mm^-1. The structure was refined to R= 0.0232 and wR = 0.0645 for 1241 observed reflections with I 〉 2σ（I）. In the title complex, each Co（II） atom is octahedrally coordinated by four O atoms from two DMSO ligands and two water molecules as well as two N atoms from SCN^- ions. The title molecules are connected to each other through intermolecular hydrogen bonds to form a 1-D structure extended by eight-membered Co2O4H2 rings.

Dissolved and Particulate Dimethylsulfoxide in the South China Sea During Winter

The distributions of particulate and dissolved dimethylsulfoxide(DMSOp, DMSOd) were studied for the first time in the surface water of the South China Sea(SCS) in January 2010. The concentrations of DMSOp ranged from 2.6 to 56.8 nmol L^(-1) with an average of 11.1 ± 2.2 nmol L^(-1), and those of DMSOd ranged from 11.8 to 335.1 nmol L^(-1) with an average of 50.0 ± 16.5 nmol L^(-1). DMSOd dominated over both dimethylsulfide(DMS) and dissolved dimethylsulfoniopropionate(DMSPd) by 1–3 orders of magnitude and represented the major dissolved dimethyl sulfur pool. In addition, DMSOp/chlorophyll-a ratios varied from 2.7 to 180.7 mmol g^(-1) with an average of 30.5 ± 9.6 mmol g^(-1). DMSOd concentrations displayed a significant negative relationship with sea surface temperature(SST) and sea surfaces salinity(SSS) in the whole study area. The distribution of DMSOd in the coastal waters was obviously influenced by the Pearl River discharge, with high concentrations appearing around the river mouth. In the offshore waters, a significant correlation was observed between the DMSOp and DMSOd concentrations, suggesting that DMSOd was mainly from the diffusion of intracellular DMSO rather than from the photochemical and biological oxidation of DMS.

Electrodeposition of La-Ni Alloy Powders in Dimethylsulfoxide (DMSO)

The brown metallic luster La-Ni alloy powders were prepared by potentiostatic electrolysis technique in dimethylsulfoxide solution at room temperature. The atomic rate of La and Ni in alloy powders are 11∶1 and 10∶1. The size of metal grains is about 0.1 to 100 μm. It shows that the micrometer powders of rare earth alloys can be obtained by controlling electrodeposition conditions. The peak potentials of -2.81 and 1.75 V are attributed to reduction of La 3+ and Ni 3+ ions, respectively. The peak potentials at -2.20 and -0.168 V are the oxidation peaks of lanthanum and nickel, respectively. When potential is more negative than -1.74 V, La(Ⅲ) and Ni(Ⅱ) will codeposit. Increasing cyclic times, the value of peak current is decreasing, and the reduction peak of La(Ⅲ) was finally disappeared.

Seasonal and spatial variations of dimethylsulfoxide(DMSO) in the East China Sea and the Yellow Sea

Seasonal and spatial distributions of dissolved and particulate dimethylsulfoxide(DMSOd,DMSOp)were measured in the East China Sea and the Yellow Sea during March–April 2011 and October–November 2011.The concentrations of DMSOd and DMSOp in the surface water were 20.6(5.13–73.8)and 8.90(3.75–29.6)nmol/L in spring,and 13.4(4.17–42.7)and 8.18(3.44–22.6)nmol/L in autumn,respectively.Both DMSOd and DMSOp concentrations revealed similar seasonal changes with higher values occurring in spring,mainly because of the higher phytoplankton biomass observed in spring.Moreover,the ratios of DMSOp/chlorophyll a also exhibited an apparent seasonal change with higher values in autumn(35.7 mmol/g)and lower values in spring(23.4 mmol/g),thereby corresponding with the seasonal variation in the proportion of DMSO producers in the phytoplankton community between spring and autumn.In addition,DMSOd and DMSOp concentrations in the surface seawater revealed obvious diurnal variations with the maxima appearing in the afternoon.

Preparation of Er-Fe Alloy Films in Dimethylsulfoxide by Electrodeposition Method

Cyclic voltammetry and chronoamperometry were used to investigate the electrochemical behavior of Fe(Ⅱ) and Er(Ⅲ) in a LiClO 4 DMSO(dimethylsufoxide) system at Pt and Cu electrodes. Experimental results indicate that the reductions of Fe(Ⅱ) to Fe(0) and Er(Ⅲ) to Er(0) were irreversible at Pt and Cu electrodes. The diffusion coefficient and the electron transfer coefficient of Fe(Ⅱ) in a 0 01 mol/L FeCl 2 0 1 mol/L LiClO 4 DMSO system at 303 K were 1 70×10 -10 m 2/s and 0 08 respectively, the diffusion coefficient and the electron transfer coefficient of Er(Ⅲ) in a 0 01 mol/L ErCl 3 0 1mol/L LiClO 4 DMSO system at 303 K were 1 47×10 -10 m 2/s and 0 108 respectively. The homogeneous, strong adhesive Er Fe alloy films containing Er of 31 39%-42 12% in mass fraction with metallic lustre were prepared by potentiostatic electrolysis on a Cu electrode in a ErCl 3 FeCl 2 LiClO 4 DMSO system at -1 75--2 50 V( vs . SCE).

CHANGES OF POLYAMINE METABOLISM IN HL-60 CELLS DURING THE INDUCTION OF DIFFERENTIATION BY RETINOIC ACID AND DIMETHYLSULFOXIDE

The polyamines putrescine, spermidine and spermine have been implicated in the regulation of cell proliferation and differentiation. In this study, the changes of intracellular polyamine contents and activity of ornithine decarboxylase, a rate-limiting enzyme in the polyamine synthetic pathway, were studied. The results showed that both retinoic acid (RA) and dimethylsulfoxide (DMSO) could elevate intracellular putrescine level by more than 2-fold over control value, then it declined gradually. In RA-treated cells, transient increase in spermidine and spermine levels was noted. In contrast, the spermidine and spermine levels in DMSO-treated cells declined to about 50% of the level of control cells at 96 h. The measurement of ornithine decarboxylase activity demonstrated that the increase of intracellular putrescine in RA and DMSO treated cells was due to the polyamine synthesis by inducing ornithine decarboxylase which reached 2 to 4-fold higher over basic level at 2 h, and above 6-fold at 16 h. These results suggest that the polyamine metabolism may be involved in RA and DMSO-induced granulocytic differentiation of HL-60 promyelocytic leukemia cells.

EXPERIMENTAL STUDY ON DIMETHYLSULFOXIDEINDUCED DIFFERENTIATION OF HUMAN ESOPHAGEALEPITHELIAL CARCINOMA CELLS

Objective The treatment of solid tumors by means of differentiation induction has not yet beengained such broken - through success as all-trans retinoic acid (ATRA) in acute promyelocytic leukemia (APL).To explore more effective inducers for solid tumor therapy, dimethyl sulfoxide (DMSO) is considered as acandidate. Methods In the present study, DMSO was used as inducer to human esophageal cancer cell lines invitro, in compared with classical inducer ATRA, in terms of morphology, cell cycle, growth inhibition, cytokeratin4 expression, gap junction-mediated dye transfer and tumorigenecity in nude mice. Results DMSO as well asATRA induced differentiation of human esophageal carcinoma cells. However, DMSO was confirmed to be moreeffective for induced differentiation of esophageal carcinoma cells than ATRA. Conclusion The results suggestedthat DMSO might have a good prospect in the treatment of solid tumors.

二甲基亚砜对提高炔雌醚药物吸收和改善其适口性的作用

为提高炔雌醚药物在饵料中的利用率以及改善炔雌醚药饵对鼠类的适口性,筛选高效、安全的农药助剂,并优化饵料配制方法。以黄毛鼠为研究对象,采用单只饲喂法,测定了溶剂二甲基亚砜(DMSO)对炔雌醚药饵适口性的影响,高效液相色谱法检测不同配制的药饵中炔雌醚的分布浓度。结果显示,DMSO-炔雌醚药饵的糙米中炔雌醚的含量为炔雌醚药饵糙米中的1.5倍;DMSO可增加炔雌醚的渗透力。此外,雌雄黄毛鼠取食DMSO-炔雌醚药饵量显著低于空白饵料,而对炔雌醚药饵的取食量随时间延长逐渐降低,雄鼠第3次取食炔雌醚药饵量较空白饵料减少37.3%;雌性黄毛鼠初次取食DMSO-炔雌醚药饵量仅为对炔雌醚药饵取食量的24.1%;且雌鼠对空白饵料的消化率显著高于DMSO-炔雌醚药饵24.6%;DMSO-炔雌醚药饵组鼠体重下降显著。本研究明确了DMSO可以达到快速高效的溶解炔雌醚,且增强其在糙米中的渗透力,可实现农药化肥减量增效的需求,有望开发为具有良好应用前景的不育剂配方。

丙烯腈与衣康酸的溶液共聚合

In order to prepare a polymer solution for making carbon fibre precusor by wetspinning,solution polymerization of acrylonitrile ( A N) with itaconic acid ( I A) was carriedoutin D M S Ousing azobisisobutyronitrile ( A I B N) asinitiator. The effects of( A N+ I A) and A I B N concentration , A Nto I Aratio,temperature on conversion rate and molecular weightwere investigated . The polymerization ratein D M S O was 2 .6 time as fast at thatin D M F. The copolymers were characterized by I Rand N M Ranalysis.

高岭土－二甲亚砜夹层复合物的形成机理

运用红外吸收光谱（ＩＲ）和Ｘ射线衍射图谱（ＸＲＤ）等手段，研究高岭土－二甲亚砜（ＤＭＳＯ）夹层复合物的形成机理．ＩＲ谱初步确定ＤＭＳＯ分子与高岭土的外羟基之间形成氢键，ＸＲＤ谱表明ＤＭＳＯ分子进入高岭土层间后，使层间距增加了４．１×１０－１０ｍ．在ＤＭＳＯ中添加少量水可促进夹层反应的进行，增大夹入量。ＤＭＳＯ分子在高岭土层间以高度取向的形式存在．

二甲基硫光化学氧化反应的动力学研究

实验研究水溶液中二甲基硫（ＤＭＳ）的光化学氧化反应的动力学。结果表明，在入射光频率与强度一定条件下，ＤＭＳ进行光化学氧化反应的速率会受到介质、ｐＨ、重金属离子的影响。Ｈｇ２＋能显著加快人工海水介质中ＤＭＳ的光氧化速率。ＤＭＳ进行光氧化的一级速率常数为４．４６×１０－５～３０．４×１０－５ｓ－１，其在光照下的人工海水介质中的半寿期为３．６ｈ。

聚丙烯腈/二甲基亚砜纺丝原液流变性及流变方程拟合

以高黏均分子量(-Mη)聚丙烯腈(PAN)为研究对象,系统研究了黏均分子量(-Mη,以下简称分子量)、温度(T)、固含量(wt)和剪切速率(γ)对聚丙烯腈(PAN)/二甲基亚砜(DMSO)纺丝原液流变性能的影响。结果表明,纺丝原液分子量和剪切速率皆存在一个临界值。在临界值之前,表观黏度随分子量增加迅速增大,随剪切速率的增加迅速降低,在临界值之后,变化趋势均趋于平缓;且临界值不随温度变化而改变;依据试验结果进行表观黏度与四因素线性相关方程拟合,经对比,计算值与实验值相差不大,可以为纺丝原液表观黏度的预测和后续纺丝工艺的改进提供理论参考。

围隔藻类水华演替过程中二甲基硫化物的含量动态

于2005年6月至7月,研究了海洋围隔不同藻类水华演替过程中二甲基硫化物的含量动态,并考察了相关环境参数对二甲基硫化物含量的影响。2个围隔实验组均出现未知藻水华-硅藻水华-甲藻水华的演替过程,这3次不同藻类水华分别对应了二甲基硫化物含量的3次高峰,表明藻类水华对二甲基硫化物含量有重要贡献。不同藻类水华的贡献有较大差异,甲藻水华的贡献最大,硅藻次之,未知藻类水华的贡献最小。实验结果还表明PO34-、NO2-和NH4+主要通过影响藻类生长状态,进而影响DMSP和DMSO的含量;NO2-和NH4+亦可能通过调节DMSP和DMSO在藻细胞内的生理功能,影响DMSP和DMSO的含量;PO43-、NO2-和NH4+与DMS含量无显著相关。