Ruthenium(Ⅲ) chloride as an efficient catalyst for the synthesis of perimidine derivatives under mild conditions

Various biologically important perimidine derivatives have been synthesized efficiently from various ketones and naphthalene- 1,8-diamine by using a catalytic amount of RuCl_3(1 mol%).This method is a very simple and high yielding reaction for the synthesis of perimidine derivatives.

Friction and wear performances of borates and lanthanum chloride in water

The antiwear and friction-reducing performances of sodium borate, potassium borate and lanthanum chloride in water were evaluated on a four-ball friction tester. The topographies, element distribution and chemical characteristics of the worn surfaces were investigated by scanning electron microscope （SEM）, energy dispersion of X-ray （EDX） and X-ray photoelectron spectroscope （XPS）. The results indicated that sodium borate, potassium borate and lanthanum chloride increased extreme pressure, antiwear and friction-reducing capacities of water to a certain extent, of which potassium borate was the best candidate. Combination of lanthanum chloride with sodium borate and po- tassium borate respectively further improved antiwear and friction-reducing capacities. Scratches of worn surfaces lubricated with water containing borates and lanthanum chloride were less severe than those lubricated with water containing borates alone. A tribochemical film mainly composed of oxides of lanthanum, boron and iron reduced friction and wear for water lubricant formulated with both borates and lanthanum chloride.

Studies on Solvent System of Cesium Chloride and Lanthanum Chloride and Synthesization of Four Types of New Compounds

This article describes the solubility data of the quaternary systems of CsCl LaCl 3 HCl H 2O(25 ℃, HCl 13% or 23%(wt)) and CsCl LaCl 3 HAc H 2O(30 ℃, HAc 42%(wt)), and the corresponding solubility equilibrium diagrams. Three new compounds, CsCl·LaCl 3·4H 2O, 2CsCl·LaCl 3·2H 2O and 3CsCl·LaCl 3·3H 2O have been found. From analysis of the systems by the X ray powder diffraction, TG DTG and DTA, the properties of the compounds are presented. The interpretation of the mechanism of Meyer′s reactions is discussed further and the synthesis method of four type new compounds is offered.

Lanthanum Chloride Inhibiting Expression of Inducible Nitric Oxide Synthase in RAW264.7 Macrophages Induced by Lipopolysaccharide

Nitric oxide（NO）and its reaction products were key players in the pathophysiology of sepsis and shock.The present study was designed to explore the effects of lanthanum chloride（LaCl3）on inducible nitric oxide synthase（iNOS）expression,at both gene and protein levels,in RAW264.7 macrophages induced by Lipopolysaccharide（LPS）.Reverse transcription polymerase chain reaction（RT-PCR）,immunofluorescence,and western blot were employed to measure iNOS gene expression,localization,and protein expression respectively.NO production in culture supernatants was detected by the nitrate reductase method.The results showed that LaCl3 significantly attenuated the iNOS gene and protein expression,as well as NO production in RAW264.7cells induced by LPS.

Reaction Kinetics of LiOH·H_2O and CO_2 Improved with Composite Silica Gel of Lanthanum Chloride

Reaction kinetics of LiOH·H2O and CO2 within a closed system were studied under the adsorption of water vapor by composite silica gel of lanthanum chloride. At the reaction temperature of 273～323 K and initial CO2 pressures of 40～100 kPa, reaction kinetics obeyed the Erofeev model. The reaction rate decreased slightly while the initial CO2 pressure reduced. When the reaction occurred at 273～299 K, the reaction rate was so low that it was almost independent of the reaction temperature. However, as the temperature rose up to 300～323 K, LiOH·H2O dehydrated its crystal water, and both the dehydrated and reaction-generated water were evaporated from solid reactant. For the dehydration rate increased, the reaction rate also increased as the reaction temperature rose. While the temperature was higher than 323 K, the reaction apparent activation energy of LiOH·H2O and CO2, was higher than 52.5 kJ·mol-1 and close to 61.4 kJ·mol-1 of the LiOH·H2O dehydrated enthalpy variable at 298 K, in which anhydrous LiOH was the major reactant and showed the reaction characteristics of LiOH crystals.

Reaction Kinetics of LiOH Improved with Composite Silica Gel of Lanthanum Chloride for Absorbing CO_2

A static method was employed to study the reaction kinetics of anhydrous lithium hydroxide (LiOH) and CO2. The reaction generated water was absorbed with the composite silica gel of lanthanum chloride to make the experiment repeatable. At the reaction temperature of 15～60 ℃ and initial CO2 pressures of 25～100 kPa, the reaction rate of anhydrous LiOH and CO2 decreased slightly with the reduction of initial CO2 pressure and the rise of reaction temperature, indicating that the reaction activation energy of LiOH and CO2 was negative and close to zero. During the middle period (1～5 min) of the isothermal reaction, the ratio of reaction efficiency was approximately the power of 0.4 to that of initial CO2 pressures. As anhydrous LiOH reacted to CO2, the solid product Li2CO3 covered on the surface of LiOH was not compact, so it did not hinder the subsequent reaction of absorbing the CO2 gas. The reaction kinetics of anhydrous LiOH and CO2 obeyed the Erofeev′s model.

ELECTROREDUCTION OF Yb(Ⅲ) ON NICKEL CATHODE IN MOLTEN CHLORIDE

１ＩＮＴＲＯＤＵＣＴＩＯＮＹｂＮｉａｌｏｙｃａｎｂｅｕｓｅｄｔｏｍａｎｕｆａｃｔｕｒｅｆｕｎｃｔｉｏｎａｌｍａｔｅｒｉａｌｓ［１，２］．ＩｔｉｓｎｅｃｅｓａｒｙｔｏｓｔｕｄｙｔｈｅｅｌｅｃｔｒｏｃｈｅｍｉｃａｌｂｅｈａｖｉｏｕｒｏｆＹｂ（Ⅲ）ｏｎＮ...

Synthesis of lanthanum tris (mono-i-octyl phthalate) and its thermal stability for polyvinyl chloride

A novel type of thermal stabilizer-lanthanum tris (mono- i -octyl phthalate) (LTMP) was synthesized by double-decomposition reaction o f sodium mono- i -octyl phthalate with lanthanum chloride at 60 ℃. Sodium m ono- i -octyl phthalate was prepared by sodium hydrate and mono- i -octy l phthalate prepared by reaction of isooctyl alcohol and phthalic anhydride in th e presence of sulfuric acid catalyst at 110 ℃. The yield of lanthanum tris (mon o- i -octyl phthalate) is about 84.5%. Its thermal stabilities were measured by heat-ageing oven test when incorporated into PVC. The experimental results show that the heat stability time is about 40min at 190 ℃ when adding 3phr (pe r hundred resin) to PVC. The thermal stability of this product is better than th at of Ca-Zn complex and basic lead salt stabilizers, and equal to that of dibut yltin dilaurate.

Effects of lanthanum(Ⅲ) on nitrogen metabolism of soybean seedlings under elevated UV-B radiation

The hydroponic culture experiments of soybean bean seedlings were conducted to investigate the effect of lanthanum （La） on nitrogen metabolism under two different levels of elevated UV-B radiation （UV-B, 280-320 nm）. The whole process of nitrogen metabolism involves uptake and transport of nitrate, nitrate assimilation, ammonium assimilation, amino acid biosynthesis, and protein synthesis. Compared with the control, UV-B radiation with the intensity of low level 0.15 W/m^2 and high level 0.45 W/m^2 significantly affected the whole nitrogen metabolism in soybean seedlings （p 〈 0.05）. It restricted uptake and transport of NO3^-, inhibited activity of some key nitrogen-metabolism-related enzymes, such as： nitrate reductase （NR） to the nitrate reduction, glutamine systhetase （GS） and glutamine synthase （GOGAT） to the ammonia assimilation, while it increased the content of free amino acids and decreased that of soluble protein as well. The damage effect of high level of UV-B radiation on nitrogen metabolism was greater than that of low level. And UV-B radiation promoted the activity of the anti-adversity enzyme glutamate dehydrogenase （GDH）, which reduced the toxicity of excess ammonia in plant. After pretreatment with the optimum concentration of La （20 mg/L）, La could increase the activity of NR, GS, GOGAT, and GDH, and ammonia assimilation, but decrease nitrate and ammonia accumulation. In conclusion, La could relieve the damage effect of UV-B radiation on plant by regulating nitrogen metabolism process, and its alleviating effect under low level was better than that under the high one.

Effect of Lanthanum (Ⅲ) on Reactive Oxygen Metabolism of Soybean Seedlings under Supplemental UV-B Irradiation

The effect of lanthanum （Ⅲ） on reactive oxygen metabolism of soybean seedlings under elevated ultraviolet-B radiation（UV-B：280~320 nm）at 0.15 and 0.45 W·cm-2 levels respectively was studied through hydroponics in the laboratory.Plasmolemma permeability and contents of malonadialdehyde（MDA）,hydrogen peroxide（H2O2）,and proline gradually increased during the imposition of UV-B radiation and subsequently decreased during recovery from UV-B stress.The dynamic tendency of catalase（CAT）activity was similar to that of the above four indices.The activity of peroxidase（POD）initially increased,then remained at a high level,and finally dropped steeply when soybean seedlings were exposed to a low dosage of UV-B radiation.However,POD activity rose throughout and declined slightly on the eleventh day when soybean seedlings were stressed by a high dosage.With the addition of La （Ⅲ） of 20 mg·L-1,the rising tendency of plasmolemma permeability and contents of MDA,H2O2,and proline were slowed down during the stress period,whereas the declining speed was accelerated during the recovery period.The activities of CAT and POD were higher than those without La （Ⅲ） in all experiments.It suggested that the regulative effect of La （Ⅲ） on antioxidant enzymes such as CAT and POD could strengthen their capacities to scavenge reactive oxygen species（ROS）,decrease contents of MDA and proline,and maintain normal plasmolemma permeability.Further more,the protective potential of La （Ⅲ） was better under low UV-B radiation than under a high one.

Effect of Lanthanum(Ⅲ) on Cytosolic Free Calcium in Isolated Rabbit Mature Osteoclasts

The effect of lanthanum （ Ⅲ ） （La^3 ＋ ） on cytosolic free calcium （ [ Ca^2 ＋ ] i ） in isolated rabbit mature osteoclasts was studied with the employment of fluo-3/AM as an intracellular calcium-sensitive fluorescent probe by using a confocal laser scanning microscope. La^3＋ does not alter basal [Ca^2＋ ]i levels and cell spread area at the concentration of 1.00 × 10^- 8 mol· L ^- 1. However, La^3 ＋ at higher concentrations （ 1. 00 × 10^ - 5 and 1.00 × 10^- 7 mol· L^- 1 ） decreases [ Ca^2 ＋ ] i levels and cell spread area, and greater decreases are observed for the higher concentrations of La^3 ＋ . Since [Ca^2 ＋ ]i affects cytoskeleton and the adhesion properties of osteoclasts, our results seem to suggest that La^3 ＋ inhibit bone resorption by decreasing [Ca^2＋]i in rabbit mature osteoclasts.

Microwave assisted synthesis,spectroscopy and biochemical aspects of lanthanum(Ⅲ) and praseodymium(Ⅲ) complexes with oxadiazole functionalised dithiocarbazinates

The new lanthanum (Ⅲ) and praseodymium (Ⅲ) complexes of the general formula [Ln(L)3] (Ln=La(Ⅲ) or Pr(Ⅲ); LK=potassium salt of dithiocarbazinates) were prepared by both, conventional thermal and by the use of microwave technology. Elemental analyses, electrical conductance, magnetic moment and electronic, infrared, far-infrared, 1H and 13C NMR spectral studies were used to characterize the complexes. The molecular weights of few complexes were determined by FAB-mass spectra. Nephelauxetic ratio, covalency parameter and bonding parameter for these complexes were also calculated. The probable structures of the complexes were proposed. The antifungal and antibacterial activities of the complexes were evaluated. The activities were correlated with the structures of the compounds.

Hydrothermal Synthesis and Crystal Structure of a New Dimeric Lanthanum (Ⅲ) Complex

A new dimeric lanthanum (Ⅲ) complex [La_2(phen)_2(C_7H_3N_2O_6)_6] (phen=1, 10-phenanthroline) was synthesized by the hydrothermal method and determined by single crystal X-ray diffraction analysis. The La(Ⅲ) ion is coordinated to seven oxygen atoms from five carboxylate groups and two nitrogen atoms from a phen ligand, forming a monocapped square antiprismatic geometry. Six carboxylate groups coordinate to two La(Ⅲ) ions in three modes which are chelating bidentate, bridging bidentate and bridging tridentate. The crystal is triclinic with space group P-1, a=1.2030(4) nm, b=1.2962(5) nm, c=1.3330(5) nm, α=104.410(5)°, β=114.048(4)°, γ=100.054 (4)°, V=1.7467 (10) nm^3, M_r=952.46, Z=2, D_c=1.811 g·cm^(-3), F(000)=944, S=1.017, μ=1.320 mm^(-1), with R1=0.0298 and wR2=0.0625.

Adsorptive Stripping Voltammetry of Ultra Trace Lanthanum（Ⅲ） Using an Alizarin S as Complexing Agent and Carbon Paste as Working Electrode

Ultra trace determination of lantanum（Ⅲ） has been studied by adsorptive stripping voltammetry methods using an alizarin S as complexing agent and carbon paste electrode as working electrode. The electrode was made from mixed of carbon powder and paraffin in micropipette tip with diameter of 4 ram. This method consists of two steps. The first step is the formation and adsorptive accumulation of metal ion with chelator at the electrode surface. The second step is stripping the complex from the electrode surface into the solution. The stripping step generates current which is recorded as voltammogram. The optimum conditions of instrumental parameter obtained were accumulation potential of 600 mV, accumulation time of 120 seconds, and pH of solution of 5.5. In this research, the limit detection obtained was 2.3348 × 10^-12 M （3.24× 10^-11μg/L） with sensitivity of 16.52 （nA/10u M） and the precision of standard solution of La3＋ with concentration of 2 × 10^-12 M, 4× 10^-12 M, 6 × 10^-12 M, 8 × 10^-12 M, and 10 × 10^-12M were 3.50%, 9.88%, 7.19%, 7.48% and 1.85% respectively. The linierity of this method is very good with correlation coefficient is 0.9780. Recovery percentage from La3＋ with concentration of 6× 10^-12 M and 10 × 10^-12 M are 108.84% and 91.51%, respectively.

离子色谱法测定复方聚乙二醇电解质散(Ⅲ)中氯离子、硫酸根和碳酸氢根的含量

目的建立同时测定复方聚乙二醇电解质散(Ⅲ)中氯离子、硫酸根和碳酸氢根含量的离子色谱法。方法色谱柱为Dionex Ionpac^(TM) AS11-HC阴离子分析柱,保护柱为Dionex IonPac^(TM) AG11-HC,以10 mmol/L氢氧化钾为淋洗液进行等度洗脱,流速为1.2 mL/min,检测器为电导检测器,抑制器为Dionex AERS,抑制电流为30 mA,柱温为30℃,进样体积为10μL;按外标法计算氯离子和硫酸根的含量,按双对数拟合的标准曲线法计算碳酸氢根的含量。结果该色谱条件下,氯离子、硫酸根、碳酸氢根能有效分离,其线性范围分别为0.055~0.219 mg/mL(r为0.9999)、0.155~0.618 mg/mL(r为1.0000)、0.065~0.121 mg/mL(r为0.9999);回收率分别为98.06%~101.34%、97.37%~101.25%、97.16%~99.81%,RSD分别为1.1%、1.3%、1.0%(n=9);精密度、准确度、稳定性、耐用性考察的RSD均小于2%。结论建立的离子色谱法简单快速,准确度、精密度和耐用性良好,可同时测定复方聚乙二醇电解质散(Ⅲ)中氯离子、硫酸根、碳酸氢根的含量,适用于该药品的质量控制。

2,9-二甲基-1,10-菲咯啉的dl-丙氨酸衍生物的合成表征及其镧(Ⅲ)配合物与 DNA作用光谱研究

以２，９－二甲基－１，１０－菲咯啉为初始原料，合成了２，９－二甲基－１，１０－菲咯啉的ｄｌ－丙氨酸衍生物：１，１０－菲咯啉－２，９－二亚甲基亚氨基－（２，２’－二甲基）二乙酸（Ｌ）。该配体经过元素分析。红外光谱、核磁共振氢谱表征。在 ２５±０．１℃、 Ｉ＝ ０．１ｍｏｌ·ｄｍ^（－３）ＮａＮＯ_３的条件下，用ｐＨ电位滴定法测定了该配体的质子化常数及其与Ｌａ（Ⅲ）的配合物的稳定常数。通过电子光谱研究了Ｌｂ（Ⅲ）的配合物与小牛胸腺 ＤＮＡ的相互作用。用溴化乙锭作为荧光探针研究了 Ｌａ（Ⅲ）－Ｌ配合物与小牛胸腺 ＤＮＡ的相互作用的过程。作为对比，也研究了 Ｌａ（Ⅲ）分别与１，１０－菲咯啉（Ｐｈｅｎ）、 ｄｌ－丙氨酸（ Ａｌａ）的配合物与小牛胸腺 ＤＮＡ的相互作用。结果表明 Ｌａ（Ⅲ）－Ｌ配合物与小牛胸腺ＤＮＡ作用既有共价键合，又有插入作用。

亚胺基二乙酸树脂对镧(Ⅲ)的吸附及其机制

研究了亚胺基二乙酸树脂(DAAR)对镧离子的吸附行为及机制,pH=5.73的HAc NaAc体系为最佳吸附条件。静态饱和吸附容量为188mg·g-1·R;表观吸附速率常数k298=2.00×10-5s-1,表观吸附活化能Ea=9.57kJ·mol-1;等温吸附服从Freundlich经验式;吸附热力学函数ΔH=10.2kJ·mol-1;ΔS=45.0J·mol-1·K-1;ΔG298=-3.17kJ·mol-1;用0.5mol·L-1HCl作解吸剂,解吸率接近100%;树脂功能基与镧离子的配位摩尔比为3∶1;化学分析及红外光谱表明树脂功能基上的O与La3+发生配位键合。

N-取代四氮杂大环镧(Ⅲ)配合物的合成及其生物活性

合成了2,2,4,9,9,11-六甲基-N1、N3-二乙酸四氮杂十四烷大环(A)和2,2,4,9,9,11-六甲基-N1、N3-二对甲基苯磺酰基四氮杂十四烷大环(B)以及它们的镧配合物,用元素分析、摩尔电导、IR和1H-NMR谱等手段表征了这些化合物的结构。初步生物活性表明,各化合物均有较强的抗肿瘤活性。

2,9—二甲基—1,10—菲咯啉的l—缬氨酸衍生物的合成表征及其镧(Ⅲ)配合物与DNA作用光谱研究

以2,9-二甲基-1,10-菲咯啉为初始原料,合成了1,10-菲咯啉的l-缬氨酸衍生物——1,10-菲咯啉-2,9-二亚甲基亚氨基-(2,2＇-二异丙基)二乙酸(L).该配体经过元素分析、红外光谱、核磁共振氢谱表征.通过电子光谱,研究了La(Ⅲ)的配合物与小牛胸腺DNA的相互作用.用溴化乙锭作为荧光探针,还研究了La(Ⅲ)-L配合物与小牛胸腺DNA的相互作用的过程.作为对比,也研究了La(Ⅲ)分别与1,10-菲咯啉(Phen)、l-缬氨酸(Val)的配合物与小牛胸腺DNA的相互作用.结果表明La(Ⅲ)-L配合物与小牛胸腺DNA作用既有共价键合,又有插入作用.

氯化钠介质中小牛胸腺脱氧核糖核酸对铈(Ⅲ)的荧光猝灭机理

在 ｐＨ＜６．２的 ＮａＣｌ介质中，Ｃｅ（Ⅲ）受 ２５４．０ ｎｍ紫外光激发所产生的 ３５０．０ ｎｍ荧光因 Ｃｅ（Ⅲ）的各种阳离子型体与小牛胸腺（ｃｔ）ＤＮＡ上的磷酸根发生静电作用而被猝灭。２０℃时荧光猝灭程度１ｎ（Ｆｏ／Ｆ）和Ｆ０／Ｆ分别与０～６．０×１０－６ｇ／ｍＬ和３．０×１０－６～８．０×１０－６ｇ／ｍＬ的 ｃｔＤＮＡ成线性关系。ｃｔＤＮＡ的这种猝灭行为与 Ｃｅ（Ⅲ）的荧光为 Ｈ２ＰＯ４的猝灭相似，猝灭等温线的斜率随温度增加略有增加。而高浓度 ｃｔＤＮＡ与Ｃｅ（Ⅲ）生成了在 ２９５．２ｎｍ处有吸收的复合物。