High temperature properties and decomposition of inorganic salts

Bibliography: pt. 1, p. 37-38.

Dispersion copolymerization of acrylamide with quaternary ammonium cationic monomer in aqueous salts solution

Dispersion copolymerization of acrylamide (AM) with 2-methylacryloylxyethyl trimethyl ammonium chloride (DMC) has been carried out in aqueous salts solution containing ammonium sulfate and sodium chloride with poly(acryloylxyethyl trimethyl ammonium chloride) (PDAC) as the stabilizer and 2,2'-azobis[2-(2-inidazolin-2-yl)propane]-dihydro chloride (VA-044) as the initiator. A new particle formation mechanism of the dispersion polymerization for the present system has been proposed. The effects of inorganic salts and stabilizer concentration on dispersion polymerization have been investigated. The results show that varying the salt concentration could affect the morphology and molecular weight of the resultant copolymer particles significantly. With increasing the stabilizer concentration, the particle size decreased at first and then increased, meanwhile the effect on the copolymer molecular weight was the contrary. These results had been rationalized based on the proposed mechanism.

Control of ordered structure and morphology of large-pore periodic mesoporous organosilicas by inorganic salt

Highly ordered rodlike periodic mesoporous organosilicas (PMO) were successfully synthesized using 1.2-bis(trimethoxysilyl)ethane as an precursor and triblock copolymer P123 as a template at low acid concentration and in the presence of inorganic salts (KCl). The role of acid and salt as well as the effects of synthesis temperature and reactant mole ratio in the control of morphology and the formation of ordered mesostructure was systematically examined. It was found that the addition of inorganic salt can dramatically expand the range of the synthesis parameters to produce highly ordered PMO structure and improve the quality of PMO materials. The morphology of PMOs was significantly dependent on the induction time for precipitation. The uniform PMO rods can only be synthesized in a narrow range of acid and salt concentrations. The results also show that the optimized salt concentration (I M) and low acidity (0.167 M) were beneficial to the formation of not only highly ordered mesostructure but also rodlike morphology. Increasing acidity resulted in fast hydrolysis reaction and short rod or plate-like particles. Highly ordered rod can also be prepared at low temperature (35 degrees C) with high salt amount (1.5 M) or high temperature (45 degrees C) with low salt amount (0.5 M). Optimum reactant molar composition at 40 degrees C is 0.035P123:8KCl:1.34HCI:444H(2)O:1.0bis(trimethoxysilyl)ethane. Lower or higher SiO2/PI23 ratio led to the formation of uniform meso-macropores or pore-blocking effect. (c) 2005 Elsevier Inc. All rights reserved.

Effect of pretreatment on the sublimation of ammonium perchlorate

The effects of pretreatments on the sublimation of pure ammonium perchlorate (AP) were studied by differential thermal analysis. The addition of inorganic salts (doping), or preheating, lead to desensitisation of the sublimation process, whereas it was sensitised by precompression. Sublimation increased with decrease in the particle size of the AP from 500 to 200 microns, but decreased with a further decrease in size from 200 to 100 microns. The results are interpreted in terms of gross imperfections and strain in the AP crystals.

Photocatalytic Activity of Combustion Synthesized ZrO(2) and ZrO(2)-TiO(2) Mixed Oxides

Tetragonal ZrO(2), synthesized by solution combustion technique, was found to be photocatalytically active for the degradation of anionic dyes. The compound was characterized by FT-Raman spectroscopy, X-ray photoelectron spectroscopy, FT-infrared spectroscopy, UV-vis spectroscopy, BET surface area analysis, and zero point charge pH measurement. A high concentration of surface hydroxyl groups was observed over the catalyst, as confirmed by XPS and FUR. The photocatalytic degradation of orange G, amido black, remazol brilliant blue R, and alizarin cyanine green (ACG) was carried out with this material. The effect of pH, inorganic. salts, and H(2)O(2) on the activity of the catalyst was also studied, and it was found that the catalyst maintained its activity at a wide range of pH and in the presence of inorganic salts. Having established that ZrO(2) was photocatalytically active, mixed oxide catalysts of TiO(2)-ZrO(2) were also tested for the photocatalytic degradation of ACG, and the 50% ZrO(2)-TiO(2) mixed oxides showed activity that was comparable to the activity of TiO(2).

Unusual Salt-Induced Color Modulation through Aggregation-Induced Emission Switching of a Bis-cationic Phenylenedivinylene-Based pi Hydrogelator

The synthesis, hydrogelation, and aggregation-induced emission switching of the phenylenedivinylene bis-N-octyl pyridinium salt is described. Hydrogelation occurs as a consequence of pi-stacking, van der Waals, and electrostatic interactions that lead to a high gel melting temperature and significant mechanical properties at a very low weight percentage of the gelator. A morphology transition from fiber-to-coil-to-tube was observed depending on the concentration of the gelator. Variation in the added salt type, salt concentrations, or temperature profoundly influenced the order of aggregation of the gelator molecules in aqueous solution. Formation of a novel chromophore assembly in this way leads to an aggregation-induced switch of the emission colors. The emission color switches from sky blue to white to orange depending upon the extent of aggregation through mere addition of external inorganic salts. Remarkably, the salt effect on the assembly of such cationic phenylenedivinylenes in water follow the behavior predicted from the well-known Hofmeister effects. Mechanistic insights for these aggregation processes were obtained through the counterion exchange studies. The aggregation-induced emission switching that leads to a room-temperature white-light emission from a single chromophore in a single solvent (water) is highly promising for optoelectronic applications.

青蒿的遗传转化及青蒿素生物合成的调控

利用发根农杆菌(Agrobacterium rhizogenes)1601，1000，1500，15834，A4，均成功地转化了中药青蒿(Artemisia annua L.)并且建立了pRi1601，pRi15834，pRiA4诱导的发根培养。pRi1601，pRi15834的发根诱导率比其它质粒高。太老或太幼的叶片不利子发根的诱导;发根主要从叶脉的伤口处萌发;带顶芽或带侧芽的叶片容易诱导根，但不一定是发根。光照有利于发根的诱导和发根的生长。以每个发根的“绝对生长速率”(Gtowth Ratio，GR)和绝对“侧根”数量(Number of Side Roots，NSR），通过大量的发根系的筛选，建立了8个发根系，1601-L-1, 1601-L-2, 1601-L-3, 1601-L-4, 15834-L-1, 1601-P-I, 16 01-P-2，15834-L-2。Southern分子检测表明，160l-1-1，1801-L-2, 1601-L-3，1601-L-4，1601-P-1，1601-P-2均为转化子。8个建立的发根系之间无论生长或者QHS的合成存在明显的差异。比较光／暗(16/8hrs)，25℃条件下培养的16 01-L-1，1601-L-2，1601-L-3，1601-L-4，1601-P-l，和1601-P-2，其中16 01-L-3的生长最快，160l-L-1的生长最慢;但是，1601-L-1的QHS的含量最高（可达1. 048%），1601-1-3的QHS的含量最低。160Z-L-3，15834 -L-1和2583:1-L-2的生长速率相差不大。用盛有l000mLMS液体培养基的3000mL的锥形瓶扩大培养1601-L -3，15834-L-1和15834-L-2，转速为ll0rlpm，培养过程中发根容易形成发根球（Hairy Root Balis，HRB），HRB的形成严重影响发根的生长和QHs的合成，HpLC分析表明扩大培养发根中QHS的含量比较低。 改变MS基本培养基中的无机离子的浓度，研究不同无机离子对发根生长和QHS的合成的影响。 l、KN03为18.79×10-3M时有利于1601- L-1生长，为14. 84×10-3M时有利于QHS的合成。NH-4N0-3浓度在10.93-12. 49×10—3M范围内有利于1601-L-1生长，在0-20.62×10-3M范围内对QHS的合成影响不大，大于20. 62×lO-3M不利QHS的合成。培养基中NH-4+／N0-3-比值为0. 37-0. 4-0.52:1时有利于发根的生长，比值为0.52 - 0.58:1时有利于QHS的合成。 2、H-2P0-4-浓度为2.498×10-3M时有利于发根的生长在0-2. 498×l0-3M范围内，随着浓度的提高，促进发根的生长。培养基中的H2P4 -的浓度在0-1.249×lO-3M的范围内，随着浓度的提高，促进QHS的合成，为1.249×10-3M时QHS的含量最高。 3、培养基中最适16 01-L-1生长的Ca-2+浓度为0.198- 0.766×10-3M，大于或小于该浓度范围，显著地抑制发根的生长。但是，在0-3.695×10-3M范围内，随着培养基中Ca-2+浓度提高，促进QHS的合成，最适Ca-2+浓度为3.695×l0-3M。 4、培养基中不加Mg-2+时，完全抑制发根生长，在0. 142×10-3M-7.506×l0-3M浓度范围内，对发根生长影响没有明显的差别。但是，HPLC和UV分析发根中QHS含量，培养基中不加Mg-2+时，发根中QHS含量最高。 5、培养基中的Fe-2+浓度在0. 25 -1．0×10-3M范围内，同时有利于16 01- L-1的生长和QHS的形成。 6、培养基中最适合予16 01- L-3生长的KI浓度为2.5ppm，大于或小予该浓度均显著地抑制发根的生长，培养基中加入KI明显地降低发根中的QHS的含量。 7、H2BO3对l601-L-l生长影响不大，HPLC分析QHS的含量，培养基中的H3BO3浓度为100ppm和400ppm，QHS的含量分别为1.69mg/g和1.80mg/g(DW)。 8、Cu-2+对1601-L-3的生长影响显著，最适合1601-L-3生长的Cu-2+浓度为1.00ppm，在0 -1.00ppm的浓度范围内，随着培养基中的Cu+浓度的提高，发根的生物量不断增加。培养基中QHS合成的最适Cu2+浓度为0.05ppm，大于或小于该浓度均显著地抑制发根中QHS的合成。 比较光培养和暗培养对发根生长的影响，结果表明光照明显地促进1601-L-l的生长，暗培养明显不利于发根的生长。最适合于发根生长的温度为25℃，大于35℃显著地抑制发根的生长，影响发根的根尖细胞的正常分裂。 改变培养基中的蔗糖浓度和在发根培养的不同时期给培养基中添加蔗糖，试验结果表明蔗糖作为碳源对1601-L-3和1601-L-1的生长具有显著的影响。 (1)培养基中缺少蔗糖显著地抑制发根的生长。 (2)发根培养的前5天时间内，蔗糖浓度为30- 60glL昀培养基最有利于发根的生长，50glL的培养基中的发根生长最快，培养基中的蔗糖浓度大于60g/L小于30g／L时，发根的生物量增加较少。 (3)发根培养至第15天时，蔗糖浓度为60g/L的培养基最有利予发根的生物量的增加。发根培养至30天时，蔗糖浓度为60-90g/L的培养基，发根的生物量的增加相差不大，但是为蔗糖浓度为30-40g/L的培养基中的发根生物量一倍。 (4)发根培养过程中，分别于第5和15天给蔗糖浓度为30g/L的培养基中添加一次或二次蔗糖，使培养基中的蔗糖终浓度相当于60g/L或90g/L，培养至30天时，添加蔗糖的培养基中的发根的干重生物量相当于不添加蔗糖培养基中的发根生物量一倍，相当于初始蔗糖浓度为60g/L和90g/L培养基中发根的生物量。 (5)随着培养基中蔗糖浓度的提高，发根干重/鲜重比显著增加。培养基中的蔗糖的消耗量与发根生物量的增加呈正相关，蔗糖消耗越多，发根生物量的增加越大。 比较pH值对发根生长和QHS合成的影响表明，灭菌前pH值在5.O-6.5范围内的培养基适合予1601-L-1的生长，小于5.O不利于发根的生长，pH5.8有利于1601-1-1生长和QHS的生物合成。发根收获时培养基中的pH值一般为4.5-5.2. pH7.O抑制发根的生长，pHl0.O对发根具有强烈的致死作用。发根在培养过程中，对培养基中的pH值具有显著的调节作用，发根能在很短的时间内(24- 48hrs)使pl:l值为5.8、6.4、7.0培养基降低到pH4. 5-5.2，pH为5.8的培养基有利于QHS合成。 比较不同基本培养基对发根生长和QHS合成的影响，试验结果表明N6、DCR、Litvay培养基有利于1601-L-1的生长，WS、White、B5培养基不利于发根的生长。DCR培养基中的QHS含量最高。 根据三水平试验选用三水平正交表来安排试验的原则，选用三水平正交表L7(3-)，研究多因子效应对发根生长和QHS合成的影响，试验结果表明，Mg2+，Fe2+，Mn-2+，NH4NO3，KN03 ,KI,Ca-2+为发根生长的主要因子，NH4N03，KNOs，Mg2+，Ca2+，肌醇为QHS合成的主要因子。 通过TLC分析发根中QHS和其它化学成分，同时比较发根和无菌苗及野生植株的化学成分，发根和无菌苗均能合成包括QHS在内的野生青蒿叶片中的大部分非挥发性的化台 物。 研究青蒿植株在发育过程中QHS的含量的变化以及发根、无菌苗和野生青蒿中QHS的合成，HP分析结果表明，l、不同的单株青蒿之间的QHS量相差很大。2、同一植株幼 叶的QHS含量比老叶的QHS含量高。3、不同单株青蒿之间达到最高QHS含量的时间不一样，开花期或开花之前。4、无菌苗（带根）或者不带根丛生芽均能合成QHS，但是带根的无菌蕾的QHS量比丛生芽中的QIS的含量高。5、不同发根农杆菌转化的发根系1601-L-1和15834-L-1都能合成ＱＨＳ。

Salt-assisted microwave demulsification

Experimental data are presented to show the influence of a very small amount of inorganic salt on the demulsification of water-in-oil emulsions. It was found that some inorganic salts could effectively enhance the demulsification efficiency and increase the light transmittance of the water separated from the emulsions. The demulsification efficiency may reach 100% in a very short time under microwave radiation.

Preparation of ferrite MFe2O4 (M = Co, Ni) ribbons with nanoporous structure and their magnetic properties

Spinel ferrite, MFe2O4 (M = Co, Ni), ribbons with nanoporous structure were prepared by electrospinning combined with sol-gel technology. The ribbons were formed through the agglomeration of magnetic nanoparticles with PVP as the structure directing template. The length of the polycrystalline ribbons can reach millimeters, and the width of the ribbons can be tuned from several micrometers to several hundred nanometers by changing the concentration of precursor. The nanoporous structure was formed during the decomposition of PVP and inorganic salts.

Citrate-gel synthesis and luminescent properties of alpha-Zn-3(PO4)(2) doped with Eu3+

By using inorganic salts as raw materials and citric acid as complexing agent, alpha-Zn-3(PO4)(2) and Eu3+ doped alpha-Zn-3(PO4)(2) phosphor powders were prepared by a citrate-gel process. X-ray diffraction, (XRD), TG - DTA, FT - IR and luminescence excitation and emission spectra were used to characterize the resulting products. The results of XRD reveal that the powders begin to crystallize at 500 degreesC and pure alpha-Zn-3(PO4)(2) phase is obtained at 800 degreesC. And the results of XRD reveal that Eu3+ exists Lis EoPO(4) ill the powder. In the phosphor powders, the Eu3+ shows its characteristic red-orange (592 nm, D-5(0) - F-7(1)) emission and has no quenching concentration.

Novel prefractionation method can be used in proteomic analysis

For the first time, a novel prefractionation method used in proteomic analysis was developed, which is performed by a novel aqueous two-phase system (NATPS) composed of n-butanol, (NH4)(2)SO4, and water. It can separate proteomic proteins into multigroups by one-step extraction. The phase-separation conditions of n-butanol solutions were studied in the presence of commonly used inorganic salts. The NATPS was subsequently developed. Using human serum albumin, zein, and gamma-globulin as model proteins, the separation effectiveness of the NATPS for protein was studied under affection factors, i.e., pH, n-butanol volume, protein, or salt concentration. The model and actual protein samples were separated by the NATPS and then directly used for gel electrophoresis without separating the target proteins from phase-forming reagents. It revealed that the NATPS could separate proteomic proteins into multigroups by one-step extraction. The NATPS has the advantages of rapidity, simplicity, low cost, biocompability, and high efficiency. It need not separate target proteins from the phase-forming reagents. The NATPS has great significance in separation and extraction of proteomic proteins, as well as in methodology.

Morphology-controllable synthesis and characterization of single-crystal molybdenum trioxide

Molybdenum trioxide nanobelts and prism-like particles with good crystallinity and high surface areas have been prepared by a facile hydrothermal method, and the morphology could be controlled by using different inorganic salts, such as KNO3, Ca(NO3)(2), La(NO3)(3), etc. The possible growth mechanism of molybdenum trioxide prism-like particles is discussed on the basis of the presence of HI and the modification of metal cations. The as-prepared nanomaterials are characterized by means of powder X-ray diffraction (PXRD), field-emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), high-resolution TEM (HRTEM), Fourier transformation infrared spectroscopy (FT-IR), X-ray photoelectron spectroscopy (XPS), and ultraviolet and visible spectroscopy (UV-vis). TEM and HRTEM micrographs show that the molybdenum trioxide nanobelts and prism-like particles have a relatively high degree of crystallinity and uniformity. BET specific surface areas of the as-prepared molybdenum trioxide nanocrystals are 67-79 m(2)g(-1). XPS analysis indicates that the hexavalent molybdenum is predominant in the nanocrystals. UV-vis spectra reveal that the direct band gap energy of the annealed molybdenum trioxide prism-like particles shows a pronounced blue shift compared to that of bulk MoO3 powder.

Citrate-gel synthesis and luminescent properties of ZnGa2O4 doped with Mn2+ and EU3+

By using inorganic salts as raw materials and citric acid as complexing agent, spinel oxide ZnGa2O4 and Mn2+, Eu3+-doped ZnGa2O4 phosphor powders were prepared by a citrate-gel process. X-ray diffraction (XRD), TG-DTA, FT-IR. and luminescence excitation and emission spectra were used to characterize the resulting products. The results of XRD reveal that the powders begin to crystallize at 500 degreesC and pure ZnGa2O4 phase is obtained at 700 degreesC, which agrees well with the results of TG-DTA and FT-IR. In the crystalline ZnGa2O4, the Eu shows its characteristic red (615 nm, D-5(0)-F-7(2)) emission with a quenching concentration of 5 mol% (of Ga3+), and the Mn shows green emission (505 nm, T, A,) with a quenching concentration of 0.1 mol% (of Zn2+). The luminescence mechanism of ZnGa2O4:Mn2+/Eu3+ is presented.

Chlorohydrin water swellable rubber compatibilized by an amphiphilic craft copolymer. I. Synthesis and characterization of compatibilizer PVA-g-PBA

The graft copolymerization of butyl acrylate onto poly(vinyl alcohol) with eerie ammonium nitrate as redox initiator in a aqueous medium has been investigated. The formation of graft copolymer was confirmed by means of IR, scanning electron microscopy (SEM), and wide-angle X-ray diffraction (WAXD). The percentage of mononer conversion and percentage of grafting varied with concentrations of initiator, nitric acid, monomer, macromolecular backbone (X-n = 1750, M = 80 000), reaction temperature and reaction time. Some inorganic salts and organic solvents have a great influence upon grafting. The reaction mechanism has been explored, and rate equations for the reaction are established. (C) 2000 John Wiley & Sons, Inc.